Endocrinologia Japonica
Online ISSN : 2185-6370
Print ISSN : 0013-7219
ISSN-L : 0013-7219
32 巻, 5 号
選択された号の論文の22件中1~22を表示しています
  • HIROSHI SUGINAMI, MARIKO YANO, KATSUYUKI HAMADA, TAKANORI ITO, KOHJI Y ...
    1985 年 32 巻 5 号 p. 583-593
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    It is known that continuous stimulation with LHRH induces a biphasic release of LH. The two pools theory is generally accepted in interpreting this phenomenon. The present study was conducted in order to elicit qualitative differences in LH included in the two pools.
    Five hundred μg synthetic LHRH was infused for 2h in 10 women in various phases of the menstrual cycle and 5h blood sampling was performed during and after the infusion. Biphasic release of LH was demonstrated in all the cases investigated. The responsiveness to LHRH was most predominant in the midcycle, followed by the luteal phase. Pools of plasma samples at 30-105 minand 150-225 minof the LHRH infusion (plasma pools I and II; corresponding to the initial and the second LH release, respectively) were subjected to isoelectrofocusing (IEF) fractionation, pH range of 3.5-10. LH in plasma was classified in terms of isoelectric point (pI); i.e. A (pI=9.13), B (8.60), C (8.16), D (7.67), E (7.24), and F (LH species migrating in the acidic pH area). Percentage of high alkaline LH species was significantly elevated in plasma pool I of the midcycle. No phasic difference was observed in the IEF profiles in plasma pool II. Consistent and significant increase and decrease in the percentage of acidic and high alkaline LH species, respectively, were observed throughout the menstrual cycle when the IEF profiles of plasma pool II were compared with those of pool I. The ratio of biological to immunological LH activities (B/I ratio) was markedly depressed in acidic LH species. The highest B/I ratios were obtained in the LH species migrating in the mid-alkaline region.
    The acidic LH species might represent the young generation of LH molecules prior to aquisition of biological potency. LH species migrating in the mid-alkaline region might be mature and bio-potent forms of the hormone. High alkaline LH species might represent LH molecules over-processed and having lost a degree of biological potency during a prolonged period of storage.
  • SHIGEO ARAKI, MITSUHIRO MOTOYAMA, KOHSHIRO CHIKAZAWA, KUNIHIKO IJIMA, ...
    1985 年 32 巻 5 号 p. 595-605
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    The present experiments were performed to study the effects of preovulatory levels of estrogen on GnRH-induced gonadotropin release. Twelve female volunteers in various phases of the menstrual cycle received estradiol infusion for 66h at a constant rate of 500μg/24h whichis grossly equivalent to its production rate during the preovulatory follicularphase. In 8 of the women, GnRH was administered concomitantly from 6h after the initiation of estradiol infusion. The administered doses of GnRH were 2.5 and 5μg/h. Blood samples obtained throughout the infusion were analysed for LH, FSH, estradiol and progesterone.
    The sole administration of estradiol failed to induce the positive feedback effect on gonadotropin release within the experimental period in the early follicular phase (days 3-7) in 4 women. In 5 women treated during the follicular phase, remarkable LH releases were induced after a lag period by the infusion of both GnRH and estradiol. The induced LH surge formed a prolonged biphasic pattern. Although a similar pattern of FSH was observed in some cases, its response was minimal compared with that of LH. In 3 women during the luteal phase, however, a combined administration of estradiol and GnRH induced only a short term release of LH which was terminated in only 12h.
    The present data indicate that 1) Preovulatory levels of estrogen affect the late part of the LH surge which is induced by constant administration of low doses of GnRH resulting in a prolonged biphasic release of LH, and 2) These effects of both hormones are not manifest in the presence of high levels of progesterone. These results indicate the possibility of a role of GnRH and estrogen in the mechanism of the prolonged elevation of a gonadotropin surge at mid-cycle.
  • MITSUHARU OGINO
    1985 年 32 巻 5 号 p. 607-613
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    The productivity of estrogens from 6 to 39 weeks of pregnancy was assessed by using human placental organ culture. It was revealed that the placenta gains the capacity to generate a significant amount of estrogens at around 8 weeks of pregnancy. Therefore, it was suggested that the luteoplacental shift takes place between 6 and 8 weeks of gestation (or 4 to 6 weeks after fertilization). The productivity of estrogens showed a distinct difference before and after 10 weeks of pregnancy when the placental localization is established. The amount of estrone formed by the placenta before 10 weeks of pregnancy was 0.043±0.005nanomoles/mg protein/hour (mean±s.e, n=6), while it was 0.034±0.002nanomoles/mg protein/hour from 10 weeks to term (mean±s.e, n=18; not significantly different) during which no marked change was observed, however that of 17β-estradiol was 0.099±0.002 nanomoles/mg protein/hour (mean±s.e, n=6) before 10 weeks of pregnancy and 0.072±0.002, nanomoles/mg protein/hour (mean±s.e, n=18) from 10 weeks to term (significant difference with p<0.005). The 17β-estradiol/estrone ratio remained almost constant throughout pregnancy, which ranged from 2.00 to 3.00.
  • YOSHINOBU KOIDE, SETSUKO INOUE, HIROKO MURAYAMA, KOICHI KAWAI, KAMEJIR ...
    1985 年 32 巻 5 号 p. 615-624
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    Effects of o, p'-DDD on parameters of cortisol metabolism were studied in 3 patients with Cushing's syndrome (ectopic ACTH-syndrome, Cushing's disease, and adrenal cancer). Before o, p'-DDD treatment, plasma cortisol, urinary 17OHCS, and urinary free cortisol were elevated in all patients. These parameters correlated well with each other in ectopic ACTH-syndrome and Cushing's disease. However, in adrenal cancer, urinary 17OHCS did not correlate with either plasma cortisol or urinary free cortisol, while the latter two parameters did. During o, p'-DDD, urinary 17OHCS rapidly declined in a patient with ectopic ACTH syndrome and a patient with Cushing's disease before plasma cortisol or urinary free cortisol decreases. Consequently the positive correlations of urinary 17OHCS with the other parameters were lost. In a case of adrenal cancer, urinary 17OHCS again did not correlate with plasma cortisol or urinary free cortisol. In these conditions, plasma cortisol and urinary free cortisol still significantly correlated.
    The present results demonstrated the limit of urinary 17OHCS as the index of the cortisol secretion rate both in some cases of adrenal cancer and in patients taking o, p'-DDD. It is suggested that urinary free cortisol should be utilized as a more accurate index for the cortisol secretion rate in such circumstances.
  • HARUO NOGAMI, FUJIO YOSHIMURA, ALBERTO J. CARRILLO, Z. DAVE SHARP, PET ...
    1985 年 32 巻 5 号 p. 625-634
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    Adult male rats were injected with different doses (1, 10, and 100μg) of 17β-estradiol daily for 5 days, and the changes in prolactin (PRL) mRNA levels were examined by in situ hibridization and cytoplasmic dot blot hybridization using cloned cDNA for rat prolactin mRNA. An increase in cytoplasmic PRL mRNA content was evident in all the animals treated with estrogen as revealed with cytoplasmic dot blot analysis. There were however, no significant differences in PRL mRNA content among the three estradiol treated groups. Cytoplasmic PRL mRNA was also demonstrated by in situ hybridization on the frozen pituitary sections using a 3H-labeled PRL cDNA probe. The number of grains per cell was increased after estrogen treatment. 3Hthymidine uptake into pituitary cells was also examined in vivo using combined techniques of immunocytochemistry and autoradiography. Although the percentage of immunoreactive PRL cells which took up thymidine in their nuclei increased to more than double after estrogen treatment, the increase in the total number of immunoreactive PRL cells was small. These results suggest that the major effect of estrogen on PRL cells is an increase in the accumulation of PRL mRNA in the individual PRL cells. The number of grains per cell was found to vary from cell to cell, both in control and estrogen treated animals. This variability is discussed in relation to the functional heterogeneity within the PRL cell population.
  • JUN KAWADA, MIKIO NISHIDA, YOSHIYUKI YOSHIMURA, KIKUJI YAMASHITA
    1985 年 32 巻 5 号 p. 635-643
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    Effect of excessive ingestion of manganese (Mn) on the mouse thyroid was assessed under the conditions of normal intake of iodide. Female mouse thyroids were enlarged after 7 weeks of administration of 200mg/l MnCl2·4H2O in drinking water; 2.74±0.25mg for control (N=56), and 3.31±0.28mg for Mn-treated group (N=85)(p<0.001). In contrast, male mouse thyroids never became goitrous following this treatment. Manganese was goitrogenic to the castrated male mouse, but it had no effect on the testosterone-treated castrated male mouse, indicating the involvement of androgen in goiter formation. Oral administration of Mn did not severely affect blocked T/S of 125I or iodine metabolism in the thyroid. A morphological study, however, revealed that the epithelial cell in the Mn-treated mouse thyroid became flatter than that of the control. The lumens were filled with colloid in Mn-treated female mouse thyroid. The serum levels of thyroxine (T4), but not triiodothyronine (T3), were slightly reduced by Mn.
    These informations suggest that Mn can be a mild goitrogen for the female mouse and that the etiology of goiter formation can be interpreted by retention of colloid in the lumen.
  • HISANORI MINAKAMI, Kozo KIMURA, KUNIHIKO IJIMA, TARO TAMADA
    1985 年 32 巻 5 号 p. 645-651
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    Although estrogen is known to stimulate the secretion of prolactin, there are only slight differences between the prolactin levels in the follicular and luteal phases in normal women. To test the hypothesis that progesterone is involved in the regulation of prolactin release, 50mg of progesterone was administered intramuscularly at 0600h to twelve hypogonadal women and blood samples were obtained at 15min intervals between 1500 and 2000h to determine the prolactin levels. The day before progesterone treatment, control blood samples were obtained at 15 min intervals between 1500 and 2000h. The serum progesterone levels were 28.7±4.1ng/ml at 1500h, 24.2±3.5ng/ml at 1730h and 21.3±2.9ng/ml (mean±SD) at 2000h. In eight of twelve hypogonadal women, progesterone lowered circulating prolactin levels significantly. These results indicate that a high level of progesterone in the luteal phase may partly block estrogen-induced prolactin release physiologically.
  • TOSHIKIYO KOH, YOSHIKATSU NAKAI, FUMIKO KINOSHITA, TOSHIHIKO TSUKADA, ...
    1985 年 32 巻 5 号 p. 653-659
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    The effect of clonidine, a central α-adrenergic agonist, on the suppression of LH release induced by β-endorphin or FK33-824, an endogenous opioid peptide or its synthetic analog, was investigated in castrated male rats, with or without pretreatment with reserpine. Pulsatile LH secretion was inhibited by intravenous injection of FK33-824 (400μg/kg), or intraventricular injection of β-endorphin (5μg). Without pretreatment with reserpine, intraperitoneal administration of clonidine (1mg/kg) failed to reverse the inhibition of LH release induced by these peptides. However, with pretreatment with reserpine (10mg/kg), clonidine abolished the inhibitory effect on LH secretion induced by these peptides in castrated male rats. These data indicate that, unlike the results in ovariectomized, steroid-primed rats, pretreatment with reserpine allows the α-adrenergic system to act more peripherally than the opioid neuronal system in a neuronal network-regulating LH release in castrated male rats.
  • YOSHITAKA TAKAHASHI, YOSHIHISA HASEGAWA, CHIAKI YAZAKI, MASAO IGARASHI
    1985 年 32 巻 5 号 p. 661-672
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    A direct method has been described which makes possible a specific assay of progesterone in rat serum without extraction.
    Anti-progesterone serum was prepared in our laboratory by the immunization of three rabbits with 4-pregnen-3, 20-dione-3 CMO: BSA. This antiserum (Gunma OGP #1) displayed little or no cross reaction with 20α-dihydroprogesterone (0.38%), pregnenolone (0.44%), 17αhydroxypregnenolone (<0.1%), 20βhydroxyprogesterone (2.4%), 17αhydroxyprogesterone (2.88%) or deoxycorticosterone (2.19%). The nonspecific inhibitory effect of serum was compensated for by adding progesterone-free serum to the standard curve tubes.
    The sensitivity of this assay was 1.1pg/tube and serum progesterone could be measured by using as little as 1μl of serum.
    The working range of the stndard curve was 1.25-2560ng/ml.
    Under the conditions of this assay (1μl of serum per tube), interference from steroid binding proteins did not affect the sensitivity, precision or reliability of the assay.
    The intra-assay and inter-assay coefficients of variation were 5.5% and 8.7%, respectively, and the assay values correlated well with those obtained by the extraction method (R=0.997, P<0.001).
    Analytical recovery indicates a close correlation between added and recovered progesterone concentrations (R=0.992, P<0.001), and the recovery rate averaged 96%.
    Compared with the extraction method, the direct progesterone assay has the advantage of speed, precision and simplicity.
    The method described is particularly suitable for routine assays of progesterone in rat serum.
  • MARI HOTTA, TAMOTSU SHIBASAKI, AKITSUGU MASUDA, TOSHIHIRO IMAKI, ICHIJ ...
    1985 年 32 巻 5 号 p. 673-680
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    The effects of intravenously given human growth hormone-releasing hormone (1-44) NH2 (hGRH-44) on growth hormone (GH) secretion were studied in normal men.
    A wide variability of intersubject GH response to hGRH-44 was observed. The peak plasma GH levels in response to 50, 100 and 200μg hGRH-44 in 7 normal men were 9.1±3.2ng/ml (Mean+SEM), 19.3±3.3ng/ml and 22.4±4.0 ng/ml, respectively. Both the mean peak values for plasma GH response to 100 and 200μg were significantly greater than that for 50μg hGRH-44 injection (p<0.01), although there was no significant difference of the mean peak plasma GH values and mean concentrations at each time point, except for those at 120min, when 100 or 200μg hGRH-44 was administered. A significant difference in the mean amount of plasma GH secreted in response to hGRH-44 was observed only between 50 and 200μg hGRH-44 injection (p<0.01). Furthermore, a dose-related plasma GH increase in response to hGRH-44 was not always observed in each subject.
    In contrast to the wide intersubject variability, the difference among responses of plasma GH to 100μg or 200μg of hGRH-44 given at multiple times separated by intervals of at least 1 week in each individual was relatively small.
    These results suggest that the wide intersubject variability could cause no dose-related GH response to hGRH-44 in doses of 50, 100 and 200μg and that the intrasubject variability was small enough to evaluate the GH secretion by a single hGRH-44 injection, a procedure not adopted before.
  • A Reverse Relationship Between the Level of Echo-Amplitude and Lymphocytic Infiltration
    AKIO YOSHIDA, TOSHIAKI ADACHI, TOSHIYUKI NOGUCHI, KEITA URABE, SUMIKO ...
    1985 年 32 巻 5 号 p. 681-690
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    In 43 patients with Graves' disease, 5 patients with painless thyroiditis and 30 patients with Hashimoto-thyroiditis ultrasonographical observations and histological examinations by needle biopsy of the thyroid were carried out simultaneously. In all cases the level of echo-amplitude was well correlated with the rate of lymphocytic infiltrations and fibrosis. In cases which exhibited marked lymphocytic infiltrations in the thyroidal biopsy specimen, no apparent echoes or very low amplitude echoes were observed in the whole thyroid and in cases in which replacement with lymphocytic infiltration was observed in almost a half part of the thyroid, several sonolucent regions were observed in the thyroid and in cases in which lymphocytic infiltration or fibrosis was observed sporadically, low-amplitude and ununiform echoes were observed in the whole or several regions of the thyroid. In cases with no lymphocytic infiltration in the histological specimen, diffuse high-amplitude and uniform echoes were observed throughout the whole lobe of the thyroid. In patients with painless thyroiditis, the amplitude of echo was low when the level of lymphocytic infiltration was high and the echo-amplitude showed a tendency to increase along with the decrease in the rate of lymphocytic infiltration. From these observations it is concluded that echo-amplitude is well correlated with lymphocytic infiltration and fibrosis in patients with Hashimoto-thyroiditis, Hashitoxicosis and painless thyroiditis.
  • HAJIME NAWATA, KAZUMI HIGUCHI, TOSHIHIKO YANASE, RYOICHI TAKAYANAGI, K ...
    1985 年 32 巻 5 号 p. 691-700
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    We investigated the mechanism of dissociation of cortisol and dehydroepiandrosterone sulfate (DHEA-S) secretion by the adrenal glands after the removal of an adrenal gland containing an adrenocortical adenoma in a patient with Cushing's syndrome. After removal of the adrenocortical adenoma, the serum cortisol rapidly decreased from 24.6±6.4μg/dl (mean±SD, n=6) to 0.7±0.5μg/dl. serum DHEA-S levels were 15±14μg/dl and 6±9μg/dl befbre and after surgery, respectively, and significantly lower than the control values. Serum cortisol levels reverted to normal levels 1.5 to 3 years after the surgery. On the other hand, DHEA-S levels reverted to normal 5 to 7 years after the serum cortisol levels had normalized.
    Monolayer cultures of normal human adrenal cells obtained at adrenalectomy in patients with advanced breast cancer and atrophic adrenal cells adjacent to the adrenocortical adenoma in patients with Cushing's syndrome were used to study the mechanism of the dissociation of cortisol and DHEA-S secretion. ACTH caused significant increases in the productions of pregnenolone (P5), progesterone (P4), 17-hydroxypregnenolone (17-OH-P5), 17-hydroxyprogesterone (17-OH-P4), DHEA, DHEA-S, androstenedione (Δ4-A), and cortisol. The amounts of 17-OH-P5 and 17-OH-P4 produced by ACTH in atrophic adrenal cells were significantly greater than those in normal adrenal cells. The amounts of DHEA, DHEA-S and Δ4-A produced by ACTH in atrophic adrenal cells were significantly smaller than those of normal adrenal cells. The conversion rate of 17-OH-[3H] P5 to 17-OH-[3H] P4 and 11-deoxy-[3H] cortisol was higher in atrophic adrenal cells than in normal adrenal cells, but the conversion rate to [3H] DHEA, [3H] DHEA-S and [3H]Δ4-A was significantly lower in atrophic adrenal cells than in normal adrenal cells.
    These results suggest that the dissociation of cortisol from DHEA-S after the removal of adrenocortical adenoma is a probably due to diminished C17, 20-lyase activity in the remaining atrophic adrenal gland.
  • TSUYOSHI KONO, ATARU TANIGUCHI, HIROO IMURA, FUMIMARO OSEKO, MAHESH C. ...
    1985 年 32 巻 5 号 p. 701-708
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    In order to clarify the importance of C-terminal phenylalanine in angiotensin II (ANG II) molecule, agonistic activities of a C-terminal substituted peptide, isoleucine8-angiotensin II (Ile8-ANG II), were studied in comparison with those of sarcosine1-, isoleucine8-angiotensin II (Sar1-, Ile8-ANG II) and isoleucine5-angiotensin II (Ile5-ANG II) in 5 normal men. When infused iv at a rate of 600pmol/kg·min for 30min, Ile8-ANG II and Sar1-, Ile8-ANG II raised the blood pressure to the same extent (15/15mmHg on the average), while the average blood pressure increase was 21/21mmHg after an iv infusion of Ile5-ANG II at a rate of 5pmol/kg·min for 30min. Duration of the pressor action after the cessation of each infusion was 50-90, 90-120 and 10-25min, respectively. In each case plasma renin activity (PRA) decreased and plasma aldosterone (PA) increased. When infused iv at a rate of 10 pmol/kg·min (maximum non-pressor dose) for 120min, both Ile8-ANG II and Sar1-, Ile8- ANG II lowered PRA and increased PA gradually, but 100mg oral captopril given immediately before these infusions caused no significant increase in PRA or no significant decrease in PA but again a decrease in PRA and an increase in PA. These results indicate that Ile8-ANG II has a very weak pressor (less than 0.83% of Ile5-ANG II and same as Sar1-, Ile8-ANG II) and slight reninsuppressing and steroidogenic actions in man and its metabolic degradation is slower than that of Ile5-ANG II and that the substitution of sarcosine for aspartic acid in the N-terminus of Ile8-ANG II further slows its metabolism. It is now evident that phenylalanine in 8 position is very important in maintaining sufficient pressor, renin-supressing and steroidogenic actions of ANG II but that this amino acid is not indispensable in maintaining more or less the biological activities of ANG II molecule.
  • SHUSO SUEMARU, KOZO HASHIMOTO, ZENSUKE OTA
    1985 年 32 巻 5 号 p. 709-718
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    Ether-laparotomy stress produced a rapid increase in rat hypothalamic CRF concentration, followed by a rapid reduction and subsequent increase. Cold-restraint stress significantly reduced hypothalamic CRF concentration at 15 min after stress onset. Serum ACTH and corticosterone levels were significantly elevated at 15 min after the onset of both stresses. The CRF responses in the medulla oblongata were not similar to the hypothalamic CRF responses. Norepinephrine concentration in the hypothalamus was reduced, whereas dopamine concentration in the hypothalamus and medulla oblongata was significantly increased. Epinephrine concentrations in these tissues did not show any significant change throughout the stress period.
    The observations lead to the following conclusions: hypothalamic CRF plays a major or role in stimulating ACTH secretion under acute stress; the reduction in hypothalamic CRF is due to an excess release in the early phase of acute stress; hypothalamic CRF and medulla oblongata CRF are controlled by different mechanisms; norepinephrine in the hypothalamus may not be involved in stimulating hypothalamic CRF secretion in the early phase of acute stress; and catecholamines are regulated differently in the hypothalamus and medulla oblongata.
  • KOJI NAKAGAWA, MIYAO MATSUBARA, TAKAO OBARA, MITSUMASA KUBO, KAZUMASA ...
    1985 年 32 巻 5 号 p. 719-724
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    The responses of pituitary and adrenomedullary hormones to insulininduced hypoglycemia were studied in 10 patients with anorexia nervosa and 7 control females of comparable age. The increases in plasma GH and PRL were significantly smaller in the patients, while the responses of GH to arginine and of PRL to TRH were indistinguishable. Plasma cortisol attained similar peak levels in both groups with higher basal levels and smaller increments in the patients. The response of plasma epinephrine was markedly lower in the patients, although urinary epinephrine showed similar increase in both groups. These results suggest the possibility that the process by which hypoglycemic stimulus causes pituitary and adrenomedullary hormone secretion is deranged in patients with anorexia nervosa.
  • Junko ISHIKAWA, Katsumi WAKABAYASHI, Masao IGARASHI
    1985 年 32 巻 5 号 p. 725-739
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    Pituitary samples were obtained from female rats at various stages of the estrous cycle, and from intact male and gonadectomized rats with and without estradiol treatment. The pituitary extracts with 60% EtOH pH 9.5, were fractionated by preparative isoelectric focusing (IEF), and immunoreactive prolactin (IR-PRL) was measured by RIA. Three types of IR-PRL molecular species were found in these IEF profiles. The first type (species A) was consistently found in an area of pH 4.5-5.4, and consisted of two main subspecies with pls 5.0 (Al) and 5.25 (A2). Species A occupied most part of pituitary IR-PRL in males, gonadectomized animals, and in females in a basal state such as diestrus (D) II 17: 00. Species A was also found exclusively in the serum at proestrus (PE) 19: 00. The amounts of species A decreased notably when the secretion became active from PE 15: 00 to 22: 00, then increased at estrus (E) 6: 00 and 10: 00 when the second type (species B), which was found in the area of pH 5.4-6.8 only in trace amounts at basal states, inceased markedly. Species B decreased again at E 17: 00, while species A fully recovered. Species B also increased when PRL biosynthesis was stimulated by estradiol in intact male and gonadectomized rats. These findings indicate that species A must be the storage and secretory type of IR-PR, and that species B must be IR-PRL in the biosynthetic process which is to be finally converted into species A. A third type (species C) was found in a region of pH 3.5-4.5 in the IEF profiles of gonadectomized animals. This species is possibly IR-PRL molecules under degradation. When the pituitary was extracted serially with 0.25M ammonium sulfate pH 5.5 (fraction AMS) first, then with 60% EtOH pH 9.5 (fraction ET), fraction AMS contained mostly species B and C, while fraction ET contained species A almost exclusively. The results obtained with this dffferential extraction roughly coincided with IEF data, though some disagreements were observed.
  • KATSUYOSHI SEKI, TADASHI UESATO, TORU TABEI, KOICHI KATO
    1985 年 32 巻 5 号 p. 741-744
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    Relaxin and human chorionic gonadotropin (hCG) were simultaneously determined in the same serum samples obtained from pregnant women. Although the secretory pattern of relaxin, in general, appeared to parallel that of hCG during human pregnancy, several discrepancies were discerned in the secretory patterns of the two hormones. The mean hCG concentration significantly differed between weeks 4-7 and 8-11 of pregnancy, but the mean relaxin concentration did not. The mean relaxin concentration began to decrease at weeks 16-19 whereas that of hCG did so at weeks 12-15. The mean relaxin concentration at weeks 4-7 was significantly higher than that at weeks 24-27, though there was no significant difference between the mean hCG concentrations in the two periods. These differences in the secretory pattern of relaxin from that of hCG indicate that relaxin secretion in pregnancy is not determined only by the circulating level of hCG. The responsiveness of the corpus luteum of pregnancy to hCG stimulation of relaxin secretion may vary as a function of the age of the corpus luteum, and this may partially account for the differences between the secretory pattern of relaxin and that of hCG observed in the present study.
  • TAKASHI ISHIHARA, TORU MORI, NORIO WASEDA, KATSUJI IKEKUBO, TAKASHI AK ...
    1985 年 32 巻 5 号 p. 745-751
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    In 10 euthyroid subjects a single 2.5mg per os dose of bromocriptine caused rapid and remarkable decreases in serum TSH. As much as a 0.85±0.18 (s.d.)μU/ml decrease from the basal level (56±9%) was observed at 5 hours.A good correlation was observed between the basal TSH level and the TSH decrease after bromocriptine (r=0.786).
    In 4 patients taking 5 to 15mg bromocriptine daily (chronic administration group), another 2.5mg bromocriptine also caused significant decreases in serum TSH, but the degree (0.42±0.03μU/ml, 43±26% of basal) and duration (maximal at 4 hours) were less than those observed in the untreated group. The lowest TSH levels in these two groups did not differ significantly (0.80±0.45 and 0.78±0.53μU/ml, respectively).
    The TSH decrease after bromocriptine in the untreated group was found not to correlate significantly with TRH induced TSH increase (r=0.300). TRH induced TSH increase in the chronic administration group was similar to or greater than that of control subjects with matched basal TSH.
    The TSH lowering effects of per os prednisolone and triiodothyronine were also studied. Prednisolone exerted a quite similar effect to bromocriptine, but a certain time lag was observed in the case of triiodothyronine.
    A single dose of bromocriptine was found to lower serum TSH levels even in euthyroid subjects. The effect was considered to be independent of TRHTSH regulation and to act directly on the TSH release.
  • AKIO TOMODA, TAKUMA HASHIMOTO, KIYOH TANISHIMA, Fujitsugu MATSUBARA, Y ...
    1985 年 32 巻 5 号 p. 753-757
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    Effects of thyroid hormones and their metabolites such as L-T1, L-T2, L-T3 and L-T4 on human erythrocyte acetylcholine esterase were studied. The activity of the enzyme of intact erythrocytes was not affected by these hormones, though studied under various conditions. The physiological significance of the binding of these hormones to erythrocyte membranes remains unclear. Our results indicate that the acetylcholine esterase is not a suitable enzyme for cytochemical bioassay for thyroid hormones.
  • HITOSHI IKEDA, TOMOAKI MITSUHASHI, KEN KUBOTA, NOBUAKI KUZUYA, HIDEMAS ...
    1985 年 32 巻 5 号 p. 759-765
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    The present study was undertaken to examine the effects of 12-0-tetradecanoyl-phorbol-13-acetate (TPA), one of the potent tumor promoting agents, on GH, TSH and PRL release by rat adenohypophyseal dispersed cells and fragments, using a superfusion technique. TPA (10-6 to 10-5M) stimulated GH release from acutely dispersed rat adenohypophyseal cells. Neither TSH nor PRL was affected, but both were increased by TRH in a dose-dependent fashion (10-9 to 10-7M). In fragments, TPA (10-8 to 10-6M) elicited a doserelated release of GH. Exposure of the fragments to 10-6M TPA for 5min promptly caused a 5-fold increase in GH release which continued for at least 40min after stopping the stimulation. The addition of somatostatin (SRIF)(10-7M) decreased basal GH release and abolished GH release induced by 10-6M TPA. In contrast to GH, neither TSH nor PRL release was affected by TPA, but both were stimulated by TRH.
    These results indicate 1) that GH release is more sensitive to stimulation with TPA in normal rat anterior pituitaries in vitro than the release of TSH and PRL, and 2) that SRIF abolishes TPA-induced GH release.
  • TSUYOSHI KONO, ATARU TANIGUCHI, HIROO IMURA, FUMIMARO OSEKO, MAHESH C. ...
    1985 年 32 巻 5 号 p. 767-769
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    Pressor activity and speed of metabolic degradation of angiotensin II-(2-7)-hexapeptide [ANG-(2-7)] were studied in 5 normal men. When infused iv at a rate of 72nmol/kg·min for 7 min, ANG-(2-7) caused a very slight but statistically significant increase in blood pressure. Average blood pressure increases at 2, 5 and 7min were 5/4, 8/10 and 8/9mmHg, respectively, and the duration of the pressor action after the cessation of the infusion (T) was 5min on the average. The pressor activity and T of this peptide were much less than or shorter than those of angiotensin II-(1-7)-heptapeptide [ANG-(1-7)] iufused previously in the same 5 normal men at a rate of 18 nmol/kg·min indicating that the pressor activity ratio of both the peptides in man is 1:>7.2 which is similar to that of angiotensin II-(2-8)-heptapeptide (angiotensin III) and Ile5-angiotensin II (Ile5-ANG II)(1:>5) and that the removal of Nterminal aspartic acid from ANG-(1-7) hastens the speed of metabolic degradation of the peptide as from Ile5-ANG II.
  • TOSHIO WATABE, KOSHI TANAKA, MITSUTOSHI HASEGAWA, SHUJI MIYABE, NAOKAT ...
    1985 年 32 巻 5 号 p. 771-779
    発行日: 1985年
    公開日: 2011/01/25
    ジャーナル フリー
    This study was designed to compare the responsiveness of adrenocorticotropin (ACTH) and cortisol secretion to corticotropin-releasing factor (CRF) in the morning and early evening in normal human subjects. Synthetic ovine CRF (1.0μg/kg) or normal saline, was administered as an i.v. bolus injection to six normal males at 900h and 1700h. Blood samples were obtained before and 15, 30, 60, 90 and 120min after CRF or saline injection. Significant increases in plasma ACTH and cortisol levels were observed in all subjects at the both time of testing after CRF injection. The net increments in the areas under the concentration curve (areas in the CRF experiment minus those in the saline control experiment) were not statistically different for both ACTH (mean ±SEM: 41.0±10.6pg/mlh in the morning: 51.1±8.9pg/mlh in the evening) and cortisol (mean±SEM: 28.5±5.07μg/dl h in the morning; 36.2±4.0μ9/dl h in the evening). Also no significant diffbrence was observed in net increment, peak level and the ratio of peak level to the basal level of ACTH and cortisol after CRF injection. There were no appreciable changes in plasma concentrations of growth hormone, thyroid-stimulating hormone or prolactin, although slight but statistically significant rises in plasma levels of luteinizing hormone and follicle-stimulating hormone were observed.
    These results suggest that there is no significant difference in responsiveness of the pituitary-adrenal axis to CRF in the morning (900h) and early evening (1700h), and thus the time of day will not necessarily have to be considered when CRF is used between these times in a clinical test to evaluate pituitary ACTH reserve.
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