Endocrinologia Japonica
Online ISSN : 2185-6370
Print ISSN : 0013-7219
ISSN-L : 0013-7219
33 巻, 6 号
選択された号の論文の22件中1~22を表示しています
  • REIKO HORIKAWA, KAZUE TAKANO, NAOMI HIZUKA, KUMIKO ASAKAWA, TAMOTSU SH ...
    1986 年 33 巻 6 号 p. 743-749
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    The effect of a long-acting somatostatin analogue SMS 201-995 on GH secretion was investigated. Eleven acromegalic patients received a single dose of 50μg SMS 201-995 administered subcutaneously, and plasma GH, IGF-I, GRF, TSH, IRI and blood glucose were determined at regular intervals. Nine of 11 patients had elevated basal plasma GH levels above 5 ng/ml. In all patients, plasma GH levels fell immediately from 39.5±17.3 ng/ml (mean± SEM) to 4.3±1.6 ng/ml (P<0.05) with a maximal inhibition of 82.9±3.3% of the basal levels and the suppression persisted for about 6 h of the observation period.
    IGF-I and GRF levels were not apparently altered. TSH and IRI levels also rapidly fell. Blood glucose levels fell slightly by 0.5h. Ten of 11 patients had pain at injection sites. Except for this, no side effects were observed. Our results show that the new somatostatin analogue SMS 201-995 may inhibit GH hypersecretion in acromegalic patients for significant periods, suggesting that this agent can be a useful clinical tool for the treatment of acromegaly.
  • SHIGENORI NAKAMURA, SHIGEKI SAKATA, HIROTO SHIMA, TAKASHI KOMAKI, NORI ...
    1986 年 33 巻 6 号 p. 751-759
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    Changes in titers of serum thyroid hormone autoantibodies (THAA) and anti-thyroglobulin (Tg) antibodies during treatment with antithyroid drugs (methimazole and propylthiouracil) were examined in two cases of Graves' disease. Effects of prednisolone and subtotal thyroidectomy were also investigated in one case (case 1). Initially both cases had only anti-T4 autoantibodies in their serum. During methimazole therapy, the titer of anti-T4 autoantibodies increased in both cases, and anti-T3 autoantibodies became detectable and their titer increased in case 2. The influence of propylthiouracil on the titer of THAA was not clear. Both prednisolone plus methimazole therapy and subtotal thyroidectomy decreased the level of anti-T4 autoantibodies in case 1. There was a significant correlation between titers of THAA and anti-Tg antibodies in both cases, although titers of and-Tg antibodies in case 1 stayed within the normal range throughout the investigation period. These results indicate that 1) methimazole treatment could induce and/or enhance the production of THAA and 2) THAA are antibodies against thyroid hormonecontainingTg molecule.
  • KENSAKU SEKIYA, HAJIME NAWATA, KEN-ICHI KATO, TOSHIHARU MOTOMATSU, HIR ...
    1986 年 33 巻 6 号 p. 761-768
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    The responses of plasma immunoreactive (IR) proopiomelanocortin (POMC)-derived N-terminal peptide (Nt), IR-β-endorphin (Ep), IR-β-lipotropin (LPH) and IR-ACTH levels to ovine corticotropin-releasing hormone (CRF) and FK 33-824 (Met-Enkephalin analogue) were studied in nine patients with Addison's disease. The basal plasma levels (mean±SE) of IR-Nt, IR-Ep, IR-LPH and IR-ACTH were significantly higher in patients with Addison's disease (4459±975pg/ml, 132±25pg/ml, 4425±1030pg/ml, 553±89pg/ml, respectively) than in the normal controls (202±38pg/ml, 7±2pg/ml, 101±18pfi/ml, 53±16pg/ml, respectively). Ovine CRF produced rapid and concomitant increases in plasma levels of IR-Nt, IR-Ep, IR-LPH and IR-ACTH. Ep and ACTH levels reached a peak at 30 min. On the other hand, Nt and LPH levels reached a peak at 60 min and these levels gradually decreased up to 120 min. The molar concentrations of these IR-peptides in plasma were changed in close parallel fashion to one another. FK 33-824 produced a pronounced and concomitant fall in IR-Nt, IR-EP, IR-LPH, and IR-ACTH levels.
    These results support the theory that Nt, Ep, LPH and ACTH are produced simultaneously from POMC as a common precursor in the pituitary gland and are secreted concomitantly under various conditions such as stimulation by CRF and inhibition by FK 33-824 in patients with Addison's disease.
  • AKIO YOSHIDA, TOSHIYUKI NOGUCHI, SHINICHI TANIGUCHI, YASUO MITANI, MAS ...
    1986 年 33 巻 6 号 p. 769-775
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    The changes in the cytosol glucocorticoid receptor (GR) content during a long-term administration of a glucocorticoid were studied to examine the mechanism of the development of steroid hormone resistance. Dexamethasone (Dex)(0.2μg/ml and 2.0μ/ml) was given to adrenalectomized rats, and the GR content was determined using the exchange assay 1, 10, 20 and 50 days after the start of administration. The activity of tyrosine aminotransferase (TAT) in the cytosol was also assayed as a measure of the biological responsiveness of these animals to the administered glucocorticoid. The dissociation constant (Kd) was elevated and the Bmaxs of the GR in the cytosol were decreased by the lower concentration of Dex. The Bmaxs decreased to 30% of the untreated controls within 24 h and this lower level was maintained as long as the hormone treatment continued. On the other hand, the cytosol obtained from animals treated with 2.0μg/ml of Dex for 20-24 days did not show any measurable amount of binding to 3H-Dex. The activity of TAT was elevated 24 h after the administration of Dex but decreased gradually and steadily with time during the experimental period. To examine the biological potency of remaining GR in the liver cytosol, 2.0μg/ml Dex was again administered after a long-term treatment. This treatment eliminated the remaining GR completely and induced TAT at almost the same rate as observed in the untreated control animals. The pattern of depletion and replenishment of the GR after a single injection of hydrocortisone in the animals that had received 2.0μg/ml Dex for 14 days followed by steroid free drinking fluid for 3 days was also determined and compared with those of the untreated control. No significant differences were observed between the two animal groups in the kinetics of depletion or replenishment of the GR. We concluded that the function of GR in the Rat liver was not distorted significantly during the course of the long-term Dex treatment.
  • KOU SAKABE, KANJI SEIKI, HIDEKO FUJII-HANAMOTO, YASUO HARUKI, HARUKO O ...
    1986 年 33 巻 6 号 p. 777-785
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    Progestin (P) target cells were identified in the pituitary gland of gonadectomized female rats which had been primed with estrogen (E). P staining was localized using the immunohistochemical avidin-biotin-peroxidase (ABP) complex method. Dark brown precipitates were primarily found over the cytoplasm of cells in the pars distalis, but not in the pars intermedia nor in the pars nervosa. The majority of P-sensitive cells in the pars distalis were identical with luteotrophs, a few being lactotrophs. These observations suggest a role of P in the regulation of production and secretion of gonadotrophins in the pituitary glands of female rats.
  • SHUICHI SHIGETOMI, MOTOKO OJIMA, SHUICHI UENO, HIDEO TOSAKI, HIROSHI K ...
    1986 年 33 巻 6 号 p. 787-794
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    A 57-year-old woman (case 1) and her daughter aged 29 (case 2) with hyperkalemia exhibited subnormal plasma aldosterone (ALD) in the face of elevated plasma renin activity. Their physical findings were normal. Their arterial blood gas analysis showed that metabolic acidosis and renal function of these cases were slightly impaired. Urinary 17-OHCS and 17-KS excretions in these cases were normal. Baseline levels of corticosterone (B) and 18-hydroxycorticosterone (18-OH-B) were clearly elevated. Plasma deoxycorticosterone (DOC), B and 18-OH-B as well as cortisol remarkable increased after ACTH injection, but the increase in plasma ALD was very small. Angiotensin II infusion in case 1 resulted in a clear rise in plasma 18-OH-B but in slight depletion of B, and no increase in ALD.
    9-alpha-fludrocortisone acetate treatment was performed in case 1. Serum potassium was normalized and blood pressure elevated from 82/52 to 120/78 mmHg. Arterial blood gas analysis was corrected.
    We concluded that these two cases with subnormal plasma ALD and hyperreninemia may exist as a congenital and familial abnormality of the final step of aldosterone boisynthesis due to the impairment of the conversion of B to ALD.
  • MEGUMI MIYAKAWA, NAOMI HIZUKA, KAZUE TAKANO, IZUMI TANAKA, REIKO HORIK ...
    1986 年 33 巻 6 号 p. 795-801
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    We produced antiserum to insulin-like growth factor I (IGF-I), and developed a specific and sensitive radioimmunoassay (RIA) for IGF-I using the biosynthetic IGF-I. This antiserum to IGF-I was specific for IGF-I; no crossreactivities with multiplication stimulating activity, porcine insulin or human growth hormone (hGH) were detected. The sensitivity was 10-25 pg/tube with 50% displacement at 125 pg/tube. The intra- and inter-assay coefficients of variation for IGF-I were 5.4 and 9.7%, respectively. The plasma IGF-I levels as determined by RIA in normal adults (N=46), patients with active acromegaly (N=31), and pituitary dwarfs (N=31) were 21.6±1.0, 157.3±17.0, and 2.5±0.3 ng/ml (Mean±SEM), respectively, indicating the levels were GHdependent. The plasma IGF-I levels were significantly increased from 2.2±0.2 to 26.5±3.2 ng/ml after hGH administrations for three consecutive days in five pituitary dwarfs. The IGF-I levels were low in patients with hypothyroidism and liver cirrhosis, but were normal in patients with chronic renal failure.
    These data confirm previous reports and this radioimmunoassay proves useful in evaluating plasma IGF-I levels.
  • SADAO HOSHINO, MITSUO SUZUKI, TADAO KAKEGAWA, MASAAKI WAKITA, YASUO KO ...
    1986 年 33 巻 6 号 p. 803-811
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    The effect of thyrotrophin releasing hormone (TRH) or human pancreatic growth hormone releasing factor (hpGRF) on growth hormone (GH) release was studied in both dwarf and normal Rhode Island Red chickens with a similar genotype except for a sex-linked dw gene. Both TRH (10 μg/kg) and hpGRF (20 μg/kg) injections stimulated plasma GH release within 15 min in young and adult chickens. The increase in GH release was higher in young cockerels than that in adult chickens. The age-related decline in the response to TRH stimulation was observed in both strains, while hpGRF was a still potent GH-releaser in adult chickens. The maximal and long acting response was observed in young dwarf chickens, suggesting differences in GH pools releasable by TRH and GRF in the anterior pituitary gland. The pituitary gland was stimulated directly by perifusion with hpGRF (1 μg/ml and 10 μg/ml) or TRH (1 μg/ml). Repeated perifusion of GRF at 40 min intervals blunted further increase in GH release, but successive perifusion with TRH stimulated GH release. The results suggest the possibility that desensitization to the effects of hpGRF occurs in vitro and that the extent of response depends on the number of receptors for hpGRF or TRH and/or the amount of GH stored in the pituitary gland.
  • KOZO HASHIMOTO, SHUSO SUEMARU, TERUHIKO HATTORI, TOSHIHIRO TAKAO, HIRO ...
    1986 年 33 巻 6 号 p. 813-820
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    An intravenous administration of (D-ala2, met5)-enkephalinamide (DALA) caused a significant elevation of plasma ACTH and corticosterone at 10 to 20 min after injection in unanesthetized freely moving rats. An intraperitoneal administration of cyproheptadine tended to reduce plasma ACTH and corticosterone levels at 60 min after injection, but it did not attenuate the DALAinduced ACTH and corticosterone elevation. A large dose of naloxone (1-10 mg/kg body weight) caused a significant elevation in plasma corticosterone, but naloxone at 10 mg/kg body weight reduced the basal ACTH level and DALA-induced ACTH elevation. When both DALA and naloxone were injected, the steroidogenic effect was attenuated. Neither DALA nor naloxone affected the basal ACTH release and CRF-induced ACTH stimulation in rat anterior pituitary cell cultures. These results suggest that DALA acts at the extra-hypophyseal level to stimulate ACTH and corticosterone and that the naloxone stimulatory effect on steroidogenesis acts on the adrenal gland or is mediated by stimulating corticosterone stimulating factors other than ACTH.
  • SATORU TAKEDA, YOSHINORI KUWABARA, MASAHIKO MIZUNO
    1986 年 33 巻 6 号 p. 821-826
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    Samples of human milk obtained from lactating women in the early postpartum period were assayed for oxytocin concentrations by specific RIA, following extraction procedures with Florisil. Mean oxytocin concentrations in human milk at postpartum day 1 to 5 were 4.5±1.1, 4.7±1.1, 4.0±1.3, 3.2±0.4, 3.3±0.6μu/ml (±SE), respectively. Oxytocin levels in milk were significantly increased by nursing (3.1±0.6, 5.3±1.0μu/ml, respectively). 3Hoxytocin in human milk was stable even after incubation at 37°C for 2 hours. The dilution curve for milk was parallel to the curve for the standard oxytocin. The chromatographic fraction of immunoreactive oxytocin was identical to that of 3H-oxytocin.
    3H -oxytocin was administered to lactating rats. Radioactivity in the neonatal gastric contents and plasma were 12.8% and 4.4% of the counts in the maternal plasma.
    It was made clear that oxytocin is stable in milk and that oxytocin in maternal blood can be transferred to mik and then to neonates.
  • YUKICHI OKUDA, KOICHI KAWAI, YOSHINOBU KOIDE, KAMEJIRO YAMASHITA
    1986 年 33 巻 6 号 p. 827-834
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    Using a non-recirculating perfusion system, we studied the time course of ketone body output from the isolated rat liver in response to various hormones and changes in pH and redox state. The release of 3-hydroxybutyrate (3-OHB) started to be suppressed within 1 min after the addition of insulin (50 mU/ml) and kept half of the basal level even 10 min after its cessation. The addition of glucagon (0.2 μM) caused an increase in both 3-OHB and acetoacetate (AcAc) outputs from fed livers within 5 min, which reached about 150% of the basal level 10 min after the infusion and maintained a constant level through out the experiment. Growth hormone (2 μ/ml) elicited a slight but significant increase in AcAc output soon after the infusion. Epinephrine (10 μM) also caused a slight increase in both AcAc and 3-OHB outputs 9 min after the infusion and maintained a significant increase even 10 min after stopping infusion. The decrease in pH of the perfusate or the addition of ascorbic acid abruptly suppressed the AcAc production. In summary, the present study clearly demonstrated the direct effects of various hormones on ketogenesis in the liver and the usefulness of a non-recirculating liver perfusion system as a tool for the study of ketogenesis.
  • AKIRA KAWAOI, MINORU TSUNEDA
    1986 年 33 巻 6 号 p. 835-841
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    In order to elucidate the maternal factors influencing the functional development of the fetal rat thyroid gland, pregnant rats were subjected to either thyroidectomy or administration of PTU or TSH and the thyroid glands of the fetuses were examined chronologically by immunohistochemistry to detect thyroglobulin (Tg), T4 and T3.
    In the group undergoing thyroidectomy, the occurrence of immunoreactive Tg, T4 and T3 was the same as in the control group in spite of slight retardation of the development of the thyroid gland. On the other hand, PTU administration caused remarkable degeneration of the hyperplastic epithelium of the follicles, where immunoreactivity of T4 and T3 was barely detectable, suggesting a transplacental effect of PTU on the fetal thyroid gland. However, Tg remained unaffected and was stained as well as in the controls.
    Injection of TSH led to a delay in the occurrence of T4 and T3 by one day, probably due to increased levels of thyroid hormone from the stimulated thyroid gland of the mother rats.
  • KAZUKO ANDO, KOSHI SAITO, KUNIHIRO YAMAMOTO, TAKESHI KUZUYA
    1986 年 33 巻 6 号 p. 843-849
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    Effect of endotoxin from E. coli on the ATP content in heart muscle, the liver and the kidney of thyrotoxic rats was studied. When endotoxin (200-400 μg) was intravenously injected to rats taking drinking water containing 2-7.5 μg T3 per ml, body temperature rose and the heart rate increased. At the same time, a marked decrease in the ATP content in heart muscle and the kidney was observed together with an increase in Na+-K+-ATPase activity. Such changes were not observed or seen only to a small extent in euthyroid rats after endotoxin administration. Endotoxin-induced ATP depletion in T3-treated rats was prevented by administration of 5 mg hydrocortisone just prior to endotoxin injection. These findings indicate that endotoxin easily causes ATP depletion in some tissue or organs in thyrotoxicosis, even if the dose of endotoxin is not enough to produce such an effect in the euthyroid. These observations are of interest in relation to thyroid storm associated with bacterial infection.
  • MORIFUMI YANAGISAWA, YOSHIHITO HARA, KENTARO SATOH, TOSHINORI TANIKAWA ...
    1986 年 33 巻 6 号 p. 851-861
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    We investigated the serial changes in the plasma levels of anti-thyroglobulin antibody (ATA) by solid-phase enzyme immunoassay, thyroid hormones and blood glucose, since spontaneous occurring lymphocytic thyroiditis (LT) has been found in spontaneously diabetic Bio Breeding/Worcester (BB/W) rat. We also observed the correlation between these levels and histological findings in the thyroid gland. The incidence of diabetes was 0% in 5 week old rats (group A), 70% in 11 week old rats (group B), and 86% in 20 week old rats (group C), while LT was observed in 0% in group A, 20% in group B and 48% in group C. Although the incidence of both increased with age, there was no link between LT and diabetes. Plasma ATA levels were 91.4±28.5 (OD492 × 1, 000, mean±SEM) in the control (14 week old Wistar Furth) rats. 49.5±15.4 in group A, 197.8±41.5 in group B, and 376.7±48.7 in group C, again showing a clear increase with age. In group C, the plasma levels of ATA in rats with LT were significantly higher than those without LT. In addition, 6 out of 11 rats without LT had abnormaly high ATA levels. In group C, the plasma levels of free 3, 5, 3'-triiodothyronine (FT3) and total thyroxine (TT4), and also the FT3/TT4 ratio were significantly lower and the plasma levels of blood glucose were higher than in the other groups. There was no difference between the plasma thyroid hormone levels in rats with LT and those without LT. These studies suggest that (1) LT may occur independently of insulitis, namely diabetes, (2) ATA levels and the incidence of LT increase with age, (3) the site of ATA production may not be confined to the thyroid gland, and (4) the derangement of glucose metabolism may be one of the factors in the decrease in plasma thyroid hormone. The BB/W rat is not only a useful animal model to use in exploring the pathogenesis of human insulin-dependent diabetes mellitus, but also spontaneous autoimmune thyroiditis.
  • KAZUYUKI YAMAUCHI, CHARLES S. HOLLANDER
    1986 年 33 巻 6 号 p. 863-873
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    The regulation of TSH secretion by E1, E2, F and F prostaglandins was studied by means of a monolayer culture system of dispersed rat anterior pituitary cells which was appropriately responsive to TRH, T3 and SRIF. PGEs and Fs induced significant increases in basal TSH release of the order of 30% at 10-9 or 10-8 to 10-5 or 10-4 M. Only PGEs accentuated the TSH release induced by a half maximal dose of TRH (10-9 M) of the order of 60% in a dose dependent manner (10-9 to 10-6 M of PGEs), whereas PGFs did not. SRIF (10-8 or 10-9 M) alone failed to alter basal TSH release but did completely inhibit the TSH response to TRH (10-9 M). SRIF also significantly inhibited both the increase in basal TSH release and the accentuation of the TSH response to TRH induced by PGEs (10-6 M) but did not diminish the enhancement of basal TSH release induced by PGFs (10-6 M). 7-oxa-13-prostynoic acid (PY1), a prostaglandin antagonist, which can act as an agonist in some systems, itself exhibited agonistic properties of PGEs with respect to basal and TRH induced TSH release. PY1 failed to inhibit the TSH release induced by all PGs, but partially inhibited the accentuated TSH response to TRH induced by PGEs. Indomethacin, PG synthetase inhibitor, did not affect basal or TRH induced TSH release in our system.
    These data suggest that PGs of the E and F series probably modulate TSH release via different mechanisms and that the PGE effect on basal TSH release differs from its augmentation of TRH induced TSH response. It is speculated that these effects of PGs may have physiological significance.
  • YASUHIKO OKIMURA, KAZUO CHIHARA, HIROMI ABE, HIDESUKE KAJI, HITOSHI KO ...
    1986 年 33 巻 6 号 p. 875-881
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    By means of human growth hormone-releasing hormone (hGHRH)-RIA using an antiserum directed toward the C-terminal region of hGHRH-(1-44)-NH2, the plasma disappearance half-time and metabolic clearance rate (MCR) of immuoreactive hGHRH (IR-hGHRH) were examined in normal subjects after an iv bolus injection of synthetic hGHRH-(1-44)-NH2 (1 μg/kg BW). The disappearance of IR-hGHRH from plasma was characterized by a biexponential decay curve, with initial distribution and subsequent metabolic t1/2 value of 5.0±1.0 and 29.6±5.4 min (mean±SE), respectively. The MCR of IR-hGHRH was 6.1±1.2 ml/min·kg. The volume of distribution of IRhGHRH was 3.3±0.4 liters. The molecular size of the plasma IR-hGHRH was not different from that of hGHRH-(1-44)-NH2 for at least 90 min after the injection of hGHRH-(1-44)-NH2 when examined by gel-filtration chromatography. This prolonged clearance of hGHRH from human plasma relative to that of other hypothalamic hormones may in part explain the sustained plasma GH rises after hGHRH injection in man.
  • YUKIO KATO, KEIKO IMAI, YOICHI HANAOKA
    1986 年 33 巻 6 号 p. 883-889
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    This study was performed to improve the purification of Xenopus vitellogenin and establish the radioimmunoassay. The procedure of purification consisted of ammonium precipitation, DEAE-Sephadex chromatography and Sephadex G-200 gel chromatography. Using this procedure, 934 mg vitellogenin was purified from 49 ml of estradiol treated female Xenopus plasma (about 19 mg/ml). Vitellogenins purified from male and female plasma after a single injection of estradiol showed good correspondence in electrophoretic patterns and amino acid compositions, indicating that vitellogenin synthesis in the male occurs in four different genes as in the female.
    The radioimmunoassay for vitellogenin was established using an antibody in the plasma obtained from rabbits injected with purified Xenopus female vitellogenin. The titer was 20, 000 times dilution of the plasma, and the minimum detectable amount of vitellogenin was 0.1μg. The cross-reactivity of this antibody with newt vitellogenin was about 65% and that of chick 6%. The cross-reaction was also observed in female bullfrog plasma.
    Vitellogenin content was increased gradually during the first 6 days after injection of estradiol in female and the elevated level of vitellogenin dropped afterward.
  • AKIKO YOSHIDA, TETSUO NISHIKAWA, YASUSHI TAMURA, SHO YOSHIDA
    1986 年 33 巻 6 号 p. 891-899
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    The present investigation was performed in order to study the properties of abnormal membrane function related to ACTH receptor-adenylate cyclase system interaction in human ACTH-unresponsive adrenocortical cancer. Two tissues of adrenocortical cancer obtained from a patient with Cushing's syndrome (CS) and a case presenting no abnormal endocrinological findings (NF) were used for in vitro studies, comparing with three normal adrenal tissues. The addition of ACTH alone and ACTH plus 10-6 M GppNHp did not enhance the adenylate cyclase (AC) activity in the CS and NF tissues. Relative insensitivity of AC to GTP, GppNHp, and cholera toxin was observed for the NF tissue, while the rate of response to GppNHp for the CS tissue which also showed relative insensitivity to GTP and cholera toxin was similar to that for the normal tissues. Forskolin which is reported to directly activate the catalytic unit of the AC complex increased the AC activity of both CS and NF tissues as well as that of the normal tissues. Therefore, the function of the catalytic unit itself may be rather well preserved in these tumor tissues. These results suggest that the lack of ACTH receptor at the cell membrane surface might be responsible for ACTH-unresponsiveness in the CS tissue, although an accelerated degradation of GTP could contribute to decreased activity of GTP-binding protein. On the other hand, it might be speculated from the present observation that post-receptor interaction of AC complex for activation of AC, especially due to insensitivity of guanine nucleotide-binding protein for guanine nucleotide and cholera toxin, may be impaired in the NF tissue and this might lead to decreased AC activity in response to ACTH in the NF tissue.
  • SHIGETO MORIMOTO, KEISUKE FUKUO, HIDEKI YAMAMOTO, SHUNJI IMANAKA, EIO ...
    1986 年 33 巻 6 号 p. 901-904
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    Calcitonin-like immunoreactivity levels were determined in urine specimens in 585 normal subjccts of various ages. Urine calcitonin-like immunoreactivity (uCTi) was measured by the midportion-specific radioimmunoassay after extraction of urine by gel chromatography on a 0.8×20 cm column of Bio Gel P-2. In 197 males and 169 females below 20 years old, significant negative correlations between the age and uCTi were observed (male: r=- 0.684, female: r= - 0.690). In 75 males and 80 females above 41 years, however, no significant correlation was observed between age and uCTi. The high level of uCTi in children could be explaind by high levels of circulating calcitonin, associated with rapid bone growth ; however the uCTi level in the elderly may not reflect the physiological significance of calcitonin for them because of a suspected age-related decrease in renal clearance of uCTi in the elderly.
  • YUKIKO YABU, KIYOSHI MIYAI, SACHIKO HAYASHIZAKI, YUICHI ENDO, NAOSHIGE ...
    1986 年 33 巻 6 号 p. 905-911
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    A simple and rapid way to measure the concentration of iodide in urine with an iodide-selective ion electrode was described. Potentiometric equilibrium was attained in less than 5 min, and a linear calibration curve was obtained over the potassium iodide (KI) concentration range of 10-2 to 10-6 M. The coefficients of variation ranged from 6.2 to 10.0% within assay, and 5.4 to 14.4% between assays. The serial dilution of 3 urine samples with different concentration of iodide showed good linear correlations passing through zero. In practice, the chloride ions in urine did not cause serious errors in the measurement of iodide at molar ratios of chloride ion to iodide up to 2×104. A good linear correlation was obtained between iodide concentrations in urine determined by the electrode method and by the conventional chemical method (r = 0.92). A linear correlation was also observed between the iodide concentrations of 24 h collected urine and those of single morning urine (r= 0.91). The normal iodide content in single morning urine specimens from 127 Japanese people was 5.3 to 62.0×10-6 moles/g creatinine.
  • MASAFUMI MATSUDA, KOHEI KAKU, TOSHIO KANEKO
    1986 年 33 巻 6 号 p. 913-917
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    We examined the effect of sulfonylureas on the level of fructose 2, 6-bisphosphate (F-2, 6-P2) in muscle using a mouse hindlimb flow-through perfusion system. The F-2, 6-P2 level in muscle was increased by adding glibenclamide or tolbutamide in a dose-dependent manner. The stimulatory potency of each drug on F-2, 6-P2 formation was parallel to its hypoglycemic potency. Sulfonylurea stimulation of muscle F-2, 6-P2 formation is thought to be an important extrapancreatic action improving the deranged carbohydrate metabolism in diabetics.
  • TOSHIHIKO INOUE, NORIAKI WATANABE, SHIRO SAITO, MASAYUKI YAMASAKI, HAR ...
    1986 年 33 巻 6 号 p. 919-927
    発行日: 1986年
    公開日: 2011/01/25
    ジャーナル フリー
    A highly sensitive and specific RIA for IGF-I has been developed using recombinant DNA-derived IGF-I of very high purity and specific antiserum to it. This assay system could detect IGF-I at as low concentrations as 20-30 ng/ml. The intra-assay and interassay coefficients of variation at various concentrations of IGF-I were 4.9 to 6.5% and 5.4 to 8.0%, respectively. The recovery rate of pure IGF-I added to plasma was 77.0±3.7%. The antiserum did not cross-react with porcine insulin, biosynthetic human insulin, hGH, hEGF, the synthetic C-domain of IGF-I or that of IGF-II, but reacted equally with an analog, Thr59-IGF-I. Plasma IGF-I was extracted by the acid-ethanol method before assay to separate IGF-I from its binding protein. When plasma IGF-I was assayed without extraction, the inhibition curves of serial dilution of plasma samples from several individuals were not parallel to the standard curve of IGF-I. The plasma concentration of IGF-I was 147±49 ng/ml (mean±SD) in 156 normal adults aged from 20-59 years. As reported by others, the IGF-I levels were low in cord plasma (41.8±23.5 ng/ml) and plasma of patients with GH deficiency (64.6±42.0 ng/ml), while its levels were high in normal children of pubertal ages (12-13 yr, 365±126 ng/ml) and in patients with Lactive acromegaly (562±115 ng/ml). This RIA system is a simple and useful method for determining plasma IGF-I in normal and diseased states.
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