Endocrinologia Japonica
Online ISSN : 2185-6370
Print ISSN : 0013-7219
ISSN-L : 0013-7219
21 巻, 1 号
選択された号の論文の11件中1~11を表示しています
  • MASAHIKO KOTANI, KANJI SEIKI, MASAKAZU HATTORI
    1974 年 21 巻 1 号 p. 1-8
    発行日: 1974年
    公開日: 2011/01/25
    ジャーナル フリー
    Histological changes in the testis, prostate, seminal vesicle and hypophysis of male rabbits were examined after ligature of the spermatic lymphatics. Testosterone in blood plasma of the spermatic veins of animals with and without ligature and/or with and without HCG treatment was simultaneously measured.
    The histological picture of the.seminiferous epithelium of the testis was inherent in the spermatogonial stage 10 days after ligature. Subsequent regeneration of the germinal epithelium varied in degree from case to case with the advancing interval, but it was conspicuous within 30 days. There was no longer sign of retrogression of the germinal epithelium 90 days after ligature. The prostate epithelium showed a slight reduction in height 10 days after ligature, but quickly returned to its normal height and picture within 30 days. The seminal vesicle and hypophysis did not seem to be influenced morphologically by the ligation of the lymphatics. Testosterone content of the spermatic vein fell abruptly after the ligation of the lymphatics, being continued for as long as 90 days.Testosterone content increased rapidly after injection of HCG into animals with and without ligature.
    It is suggested from the present results that the regeneration of the germinal epithelium of the testis after obstruction of the spermatic lymphatics may depend on the formation of a collateral lymphatic circulation and that the Leydig cells are functionally supressed by lymph congestion within the testis.
  • SADAMU YAMAMOTO, TETSUO SATOH, RYOKO SAITO
    1974 年 21 巻 1 号 p. 9-12
    発行日: 1974年
    公開日: 2011/01/25
    ジャーナル フリー
    Spontaneous ovulation was inhibited in female rats with isocarboxazid (IC), MAO-Inhibitor. Administration of HCG to IC-treated females at 3:00p.m. on the day of proestrus induced ovulation. Although the brain serotonin level was still high (1.5 times the control) from 9:00a m. to 6:00p.m. on the next day after IC-injection, ovulation occurred on the second day morning. Female rats, with the increased brain serotonin level by IC-injection, copulated on the afternoon of proestrus, and ovulation occurred in the mated animals on the next morning. These results indicate that the stimulus provided by mating may overcome the inhibitory effects of serotonin in IC-treated females.
  • KENJI SHIMA, SEIICHIRO TARUI
    1974 年 21 巻 1 号 p. 13-18
    発行日: 1974年
    公開日: 2011/01/25
    ジャーナル フリー
    The effect of physiological dose of purified secretin on glucose-stimulated insulin secretion was studied in healthy volunteers during a continuous infusion of glucose. The intravenous injection of ten unit of secretin during the infusion of glucose caused a greater rise in plasma insulin level and a more marked decrease in blood glucose concentration than either the infusion of glucose or secretin alone did, resulting in a significant increase in the insulinogenic index. One unit of secretin has no effect on plasma insulin and glucose concentrations in the fasting or hyperglycemic state.
    The physiological role of secretin in regulating insulin secretion after ingestion of food was discussed.
  • YOSHIKAZU KUROKAWA, YOICHIRO KOJIMA, KORO SAKODA, HACHINEN AKITA
    1974 年 21 巻 1 号 p. 19-27
    発行日: 1974年
    公開日: 2011/01/25
    ジャーナル フリー
    The effect of splenopneumopexy on hyperaldosteronism caused by constriction of the thoracic inferior vena cava was studied. In the experiments, the double isotope dilution derivative method of Brodie et al. (1967) have been used and found to be an adequate and reliable method for the study of aldosterone in peripheral plasma. Hyperaldosteronism following thoracic inferior vena caval constriction was significantly relieved by a portopulmonary shunt. Ascites was well controlled. Improvement of systemic and hepatic hemodynamics which allow aldosterone metabolism to proceed seems the most likely mechanism.
    Our data support the clinical impression that splenopneumopexy is an effective procedure to control the ascites associated with portal hypertension, especially in the Budd-Chiari syndrome.
  • KAZUKO SERISAWA, YASUMASA ARAI
    1974 年 21 巻 1 号 p. 29-31
    発行日: 1974年
    公開日: 2011/01/25
    ジャーナル フリー
    Newborn male rats were injected with varying doses of LH or HCG from Day 1 (=the day of birth) to Day 2 and castrated on Day 3. At approximately 30 days of age they received subcutaneous ovarian transplantation. At autopsy on Day 60, ovarian grafts from saline controls contained numerous corpora lutea. Most of the saline-treated rats become “feminine males”. However, neonatal treatment with LH or HCG significantly reduced the incidence of “feminine males”. The minimal effective dose which is capable of masculinizing gonadotropin (GTH) regulation in a majority of rats seemed to exist between 1μg and 0.1μg for LH, and around 0.1 IU for HCG. Most of the rats receiving above the dose had a polyfollicular ovarian graft. These results suggest that if GTH level in the neonatal male rat is increased by injection of exogenous hormone the masculinization of GTH regulation is accelerated.
  • NORIO OGAWA
    1974 年 21 巻 1 号 p. 33-38
    発行日: 1974年
    公開日: 2011/01/25
    ジャーナル フリー
    The present study was performed to aim to the development of the in vitro assay method for growth hormone releasing factor (GH-RF) activity in the rat stalk-median eminence (SME), and to reveal the relationship between GH-RF activity in SME and plasma GH levels under ether-laparotomy stress in the rat.
    SME extract was incubated with a total of 8 quartered anterior pituitaries. GH released into the medium was measured by polyacrylamide gel disc electrophoresisdensitometry system, and was used as an index of GH-RF activity. Plasma GH levels were estimated by the Rat GH radioimmunoassay kit (NIAMD).
    Under manual handling, no significant change occurred in the levels of GH-RF activity in SME and in plasma GH levels. The ether-laparotomy (EL) stress caused a significant rise in GH-RF activity in SME at 15min and reciprocally a significant decrease in plasma GH at 5min and 15min after starting of EL stress. Namely, there was an inverse relationship between the response of GH-RF activity in SME and that of plasma GH under EL stress. These findings may suggest that the EL stress depress the GH secretion via the hypothalamus, and diminition of GH secretion could be attributed to inhibition of GH-RF release or increased secretion of an inhibitory factor.
  • IKUKO MORIYAMA
    1974 年 21 巻 1 号 p. 39-49
    発行日: 1974年
    公開日: 2011/01/25
    ジャーナル フリー
    In this study, ovarial steroid hormone was administered in ovariectomized or immature animals to observe the onset of RNA synthesis by uterine tissue in response to this hormone as well as the characteristics of newly synthesized RNA.
    After extracting RNA from the uterine tissue of rats and rabbits, the sample was analyzed with sucrose density gradient.
    While using DNA of rabbit liver as the template, the inhibition on hybrid formation of 3H-labelled estrogen dependent RNA or progesterone dependent RNA by addition of a large dose of unlabelled RNA was studied in the same tissue and in different tissue. This was also studied between RNA in the uterus treated with estrogen alone and that in the uterus of animals treated with estrogen and progesterone. As a result, a constant competition curve was obtained along with the increase of unlabelled RNA among RNA of the same kinds.
    The competition between labelled E-RNA-unlabelled E.P.-RNA was not much different from that in the experimental system between labelled E-RNA-unlabelled ERNA in the system of labelled E.P.-RNA-unlabelled E-RNA. In the system of labelled E.P.-RNA-unlabelled E-RNA, the competion was decreased by about 10% in comparison with the combination with unlabelled E.P.-RNA.
    Hybrid formation of labelled E-RNA against rabbit liver DNA was not subjected to competition by unlabelled E. coli-RNA, liver-RNA and human placenta-RNA, but a marked competion by unlabelled rabbit placenta-RNA was noted.
    According to these results, administration of progesterone following estrogen pretreatment resulted in the possibility of the opening of a gene locus apart from estrogen in the uterine cells, leading to RNA-transcription.
    Cosiderable qualitative common characteristics were noted between placenta and uterus RNA.
    E. coli and human placenta RNA show a different base composition or arrangement and form scarcely any hybrid with rabbit DNA.
  • Possible Role of the Bed Nucleus of Stria Terminalis and the Amygdala
    EI TERASAWA, MASAZUMI KAWAKAMI
    1974 年 21 巻 1 号 p. 51-60
    発行日: 1974年
    公開日: 2011/01/25
    ジャーナル フリー
    Direct effects of estrogen on the brain inducing ovulation have been studied on the late night of diestrus II in 4-day cyclic rats. Injection of 3mg of progesterone on the evening of diestrus II (23:00) delayed ovulation. However, the inhibitory effect of progesterone was restored by the simultaneous injection of estradiol benzoate (8/10) or bilateral implantation of crystalline estrogen into the medial amygdala (8/12). Implantation of estrogen into the medial preoptic area, the bed nucleus of the stria terminalis and the lateral amygdala resulted in making ovulated rats fewer such as, 1/8, 3/8 and 1/6, respectively. Positive feedback effect of implanted estrogen into the medial amygdal a blocked by chronical transection of the surrounding area of the bed nucleus of the stria terminalis (0/5). Estrogen implantation to the medial amygdala and the bed nucleus of the stria terminalis on the night of diestrus II overcame the inhibitory effect of progesterone on LH release during the critical period of proestrus, while estrogen implantation to the medial preoptic area was relatively ineffective. Thus, estrogen appears to feed back to the medial amygdala and the bed nucleus of the stria terminalis inducing the release of ovulatory hormone.
  • SHINOBU YONETANI, MASAMITSU JOJIMA, YOSHISUKE SUZUKI
    1974 年 21 巻 1 号 p. 61-68
    発行日: 1974年
    公開日: 2011/01/25
    ジャーナル フリー
    By using 4-day cycling rats, the influence of forced immobilization and a simplesurgical operation of cervical region, applied on the day of proestrus upon the expected ovulation on the following morning, were studied. When these treatments were given so as to cover the “critical period”, the ovulation was effectively blocked and the complete blockade was established by the 4hr of forced immobilization alone, or the 2hr of that with the surgical operation, where the ovulation was delayed by one day and the vaginal diestrus lasted for 3days after the vaginal estrus of one day.
    Administration of rat hypothalamic extract or LH normalized the precipitation of the periodical ovulation in the rat, treated with the 2-hr immobilization and the surgical operation. The stimuli derived from these stressful treatments seemed to exert an inhibitory effect on LH-RF releasing mechanism to block the pre-ovulatory surge of LH and resulting in the delay in ovulation. Although a similar delay in ovulation was observed in pentobarbital anesthesia, its subsequence of the vaginal cytology was evidently different from that obtained in the stressful treatment. Different mechanisms would function in CNS, between the blockade response of the anesthesia and that of the forced immobilization with a surgical operation performed under arousal state.
    Only the ether inhalation among anesthetics used in unrestrained rats at the critical period had no effect on the periodical ovulation. It is noteworthy that the blockade of ovulation by the forced immobilization with a surgical operation can be prevented by the simultaneous application of ether anesthesia.
  • HIROYOSHI HORIKOSHI, YOSHISUKE SUZUKI
    1974 年 21 巻 1 号 p. 69-79
    発行日: 1974年
    公開日: 2011/01/25
    ジャーナル フリー
    Estradiol-17β(E-2), estrone (E-1), progesterone (P), and 20α-hydroxypregn-4-en-3-one (20α-OHP) were measured in peripheral plasma on every 2-4 hr throughout the 4-day estrous cycle and the early pseudopregnancy in rats illuminated 14 hr a day (0500 to 1900). The radioimmunoassay and the competitive protein binding assay were respectively used for the measurements of estrogens and progestins.
    In the estrous cycle, E-2 showed a single rise spread from 1600 of diestrus to 1500 of proestrus, where a maximum value at around 0800 of proestrus was followed by an abrupt drop to the basal level by 2000 of the same day. Increasing tendencies of E-1 level at around 2000 of diestrus and around 1800 of proestrus were found, though showing relatively large variations. In progestins in the cycle, P showed significant rises in the evening between 1600 and 2200 every other day, i.e., on the days of proestrus and metestrus. Since daily rises of 20α-OHP were observed between 1600 and 2200 except on the day of proestrus, the total progestin (P 20α-OHP) manifested clear daily rhythmic fluctuation, having a peak every evening in the cycle.
    In the first 3 days of pseudopregnancy (PSP), E-2 remained essentially unchanged at a low level, but E-1 showed a significant rise from the late afternoon to the night of Day 1 of PSP. On the other hand, P showed significant rises in the morning (0800) and a much higher rise in the evening (2000) on Day 1 of PSP. The latter rise was also accompanied with the increasing tendency of 20α-OHP. The total progestin did not show appearent daily rhythm during the early PSP. It is revealed that sex steroids patterns during the early PSP are not so simple as hertofore assumed.
    Induction of PSP by the single injection of P was possible only at the fixed time (0700-1000) on the day of estrus throughout the estrous cycle. An important role of extraperiodical P secretion found on the day following the cervical stimulation (Day 1 of PSP) was suggested as a possible intervening mechanism for inducing PSP.
  • HIROSHI KATO, TADASHI TORIGOE
    1974 年 21 巻 1 号 p. 81-87
    発行日: 1974年
    公開日: 2011/01/25
    ジャーナル フリー
    A specific and sensitive radioimmunoassay method for oxytocin and its application to the measurement of human plasma oxytocin levels are described. Antiserum tooxytocin was prepared in guinea pigs by repeated subcutaneous injections of synthetic oxytocin emulsified in complete Freund's adjuvant. The labeled oxytocin was purified by a complex procedure with gel filtration on Sephadex G-10 column and salt gradient column chromatography on DEAE-Sephadex A-25. Separation of antibody-bound hormone from free hormone was performed by a double antibody method. Sensitivity of the assay was 0.02mIU/ml and arginine-and lysine-vasopressins showed no competition in this assay system. The recovery of the unlabeled oxytocin added to the late pregnancy plasma was 61.5±7.0 per cent, without any extraction procedure.
    Plasma oxytocin levels during human labor are also described. An evident correlation was found in plasma oxytocin levels between maternal and cord venous blood (r=0.74). Oxytocin levels in cord plasma were significantly higher than in maternal plasma. During the second stage of labor, no significant changes of oxytocin levels were noted in maternal peripheral venous blood.
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