A patient, 38-year-old man, with hemorrhage into a prolactin-secreting pituitary adenoma, or pituitary apoplexy, is reported. On his admission, clinical examinations revealed typical stigmata indicating that he suffered from an acute attack of pituitary apoplexy probably induced by acute meningitis. He survived the acute attack and recovered spontaneously without an urgent operation. Although there was no suspicious sign and symptom of hypopituitarism, the first study performed immediately after the attack suggested strongly that hypopituitarism might acutely developed during the hemorrhage into the tumor. Moreover, the follow-up studies indicated that TSH, LH and ADH recovered spontaneously from the initial damage following the resorption of hemorrhage for the next 3 months.

抄録全体を表示

Early effects of thyrotropin (TSH) in vivo and in vitro on the apical surface of thyroid follicular cells of rats pretreated with thyroxine were observed with a scanning electron microscope by applying our improved technical method. Numerous large pseudopods appeared and also in some cases apertures were observed at the apices of these pseudopods after the short interval after TSH stimulation in vivo. The effect of TSH in vitro was essentially the same as that in vivo.
The formation of pseudopods was correspondingly stimulated in vivo by the administration of propylthiouracil (PTU) within the short interval (1.5 hr). The pattern of pseudopod formation by PTU was different from that observed in TSH stimulation. The early effect of PTU coincides with our previous biochemical result that thiouracil in vivo might acutely stimulate the activity of engulfment of intrafollicular colloid.
It was demonstrated by the transmission electron microscope that the polystyrene beads, 0.25μm in diameter, could enter the cells presumably through the aperture opened at the appex of the pseudopod when they were placed in the incubation medium containing TSH. This fact suggests that the pseudopods play an important role in the endocytic process regardless of the nature of engulfed materials.
Despite the diurnal changes of thyroid activity in the normal rats, no cyclic changes of pseudopods were observed with the scanning electron microscope. The normal pattern of colloid resorption under physiological conditioni was discussed through the comparison of TSH concentration with the morphological changes of pseudopods.

抄録全体を表示

It was found that ACTH greatly reduced lipogenesis in fat cells in the presence of calcium ion, but not in the absence of calcium ion. Of the enzymes involved in triglyceride synthesis from fatty acid in lipid micelle membranes, only acyl-CoA synthetase was inhibited by calcium ion, the apparent Ki value of calcium ion being 4.2×10^-4M. The Km values of the enzyme for palmitate and ATP were 2.0×10^-4m and 2.5×10^-4m, respectively and calcium ion caused non-competitive inhibition with both palmitate and ATP. The acyl-CoA synthetase activity of lipid micellemembranes was inhibited by treatment with phospholipase A or C, but not by treatment with phospholipase D. The mechanism of inhibition of triglyceride synthesis by ACTH is discussed on the basis of these results.

抄録全体を表示

Wistar-Imamichi male rats were slowly infused with synthetic TRH (T), LRH (L) and T+L in combination for of 1, 3, 24, 48 and 72hr. Doses of the releasing hormones were 1μg/hr. For each duration of infusion, pituitary and serum TSH, LH and FSH concentrations were radioimmunoassayed. When T is infused, the pituitary TSH concentration increases at 72hr. When L is infused, it increases at 48hr but decreases at 72hr. When T and L are combindedly infused, it decreases at 24hr, but increases at 72hr. The serum TSH concentration increases at all the durations of T infusion, but is not changed after the L infusion. The T +L infusion results in a rise of the serum TSH concentration at 1, 24 and 72hr. The pituitary LH concentration increases at 48 and 72hr of the T infusion, but decreases for the whole duration of the L infusion. The T+L infusion increases the pituitary LH concentration at 24 and 48hr. The serum LH concentration does not tend to rise after the T infusion, but increases at 24, 48hr after the L infusion. The T+L infusion increases less progressively the serum LH concentration at 24, 48 and 72hr than the L infusion at the corresponding hours. The pituitary FSH concentration decreases after the 3-hr T infusion and after the 24- and 72-hr L infusions. The T+L infusion does not change the pituitary FSH concentration. The serum FSH concentration declines with the prolongation of T infusion, and a tendency of slight decreaseis observed after the L and T+L infusions. It is postulated from these results that T may be either an inhibitor to the FSH-release or a stimulator to the pituitary LH-synthesis. It is also speculated that T may act antagonistically upon the releasing effect of L, and that L may suppress the FSH-release.

抄録全体を表示

In order to investigate the role of 18-hydroxy-11-deoxycorticosterone (18-OH-DOC) in essential hypertension (EH), the responses of plasma 18-OH-DOC to 7 stimulation tests (furosemide test, adrenal suppression test, angiotensin II infusion test, adrenal stimulation test, metopirone test, saline infusion test and potassium chloride infusion test) and the circadian rhythm were investigated in 18 patients with essential hypertension (low renin group: 8, and normal renin group: 10).
From the present study, it might be thought that plasma 18-OH-DOC does not play an important role in the suppression of PRA in patients with low PRA.

抄録全体を表示

Young male rats were slowly infused with synthetic TRH, 1μg/hr, for 1, 3, 24, 48 and 72 hr, respectively. In the control rats, the basophils of the pituitaries can be divided, in their cytological properties, into the II-(classical thyrotrophs), II/III-, III-(classical LH-cell), and III/IV-type cell. The typical IV-type cells (classical FSH-cell), however, are scarcely found in the young rats. Following 1-hr infusion of TRH, the II-type cells decrease in number with the advancement of granular release, but morphological changes are not yet concrete on the other types of basophils. The II-type cells are quickly invisible following a 3-hr infusion, while the III- and III/IV-type cells remain without any significant changes. The III- and III/IV-type cells are progressively degranulated after a 24-hr infusion. The diameter of secretory granules is reduced to 100-150 nm. The smallest ones, below 50 nm in diameter, are disintegrated to disperse into the ground matrix. After degranutlaion, the III/IV-type cells appear to revert to the polygonal or stellate cells with the identical fine structure with the II-type cells. There is evidence that the thyroidectomy cells may develop from the III/IV-type cells only after a 48-hr infusion. After 72 hr, most basophils are provided with the uniform structure of “reversionary II-type cells”. In reference to the high serum TSH concentration and no significant change of pituitary TSH concentration under the same experimental condition (Soji, 1978), the present author conclusively postulates that the degranulation of the III/IVtype cells may mainly reflect the conspicuous elevation of serum TSH concentration. The above morphological results are contradictory a plausible view that TRH acts only upon the thyrotrophs to release TSH. The fact that all the basophils ultimately take an appearance of “reversionary II-type cells” in the gland by the prolonged infusion of TRH may not only suggest the share of responsiveness of all the basophils to TRH, but also support the hypothesis of secretory cycle of the basophils.

抄録全体を表示

Young male rats were iv infused with synthetic LRH (L) and with L and TRH (T) in combination for 1, 3, 24, 48 and 72 hrs at each dose of 1μg/hr. All the basophils of the controls infused with saline are divided into the continuous cyclic types, i. e., II-, II/III, III-, III/IV- and III/IV/II-types. The II-, III-and III/IV- type cells correspond, infine structure, with those of the classical thyrotrophs, LH- and FSH- gonadotrophs, respectively. A 1-hr infusion of L does not induce any serious changes in all the basophils. After a 3-hr infusion of L, the II-type cells disperse from the gland, while the III/IV-type cells diminished the number of their small secretory granules, and the lumina of endoplasmic reticulum are closed. After a 24-hr infusion, the irregularly shaped III/IV/II-type cells which may revert from the III/IV- to the II-type cells are accumulated, whose secretory granules are remarkably reduced in diameter (50-100nm). There is evidence to show the diffusion mechanism of the secretory granules into the ground matrix. After a 48-hr infusion of L, most basophils take an appearance of III/IV/II-type cells; after a 72-hr infusion, all the basophils show the homologous fine structure. Thus, the morphological changes of the basophils following the L infusion resemble intrinsically those following the T infusion (Soji, 1976b). From these results, it is tentatively concluded that L does not act only on the III-type cells analogous to the “LH-cells”, but universally upon a series of basophils.
The transformations of the III/IV-type cells into the III/IV/II-type ones and those of the II-type ones into the III- or III/IV-typeones due to a slow infusion of L are inhibited to some extent by the infusion of T+L. The granular releases from the III/IV- and II-type cells due to a slow infusion of L are also inhibited to some extent by the infusion of T+L. For this reason, both T and L may act, not synergistically but antagonistically, upon the transformation of a series of basophils and the ir granular release.

抄録全体を表示

In one case of untreated Hashimoto's thyroiditis, the serum thyroxine (T₄) value, obtained by radioimmunoassay (RIA) employing resin to separate bound and free T₄, was significantly lower than that obtained by competitive protein binding analysis (CPBA). The discrepancy was found to be due to the presence of anti-thyroxine autoantibody in the serum. This phenomenon is considered to be of practicalimportance in interpreting the T₄ value by RIA in cases with autoimmune thyroid diseases.

抄録全体を表示

Five-day-old female rats were androgenized with 1, 000 or 100μg testosterone propionate and were examined regarding the response to LHRH at 4, 7 and 12 weeks of age by measuring peripheral LH concentrations. The order of magnitude in LH release was 7>4>12 weeks old, whereas in normal rats, 4>12>7 weeks old. LH release in 4- and 7-week-old rats was higher than that in normal controls at the respective age, but was much- lower than that in normal controls 12 weeks old. The LH release by Des-Gly¹⁰-(D-Ala⁶)-LHRH-ethylamide (TAP127) was greater than that by natural LHRH both in normal and androgenized rats at 7 or 12 weeks old.
The results indicate that the pituitary gland in androgenized rats responds to LHRH to a much larger extent during the premature period and its responsiveness declines during the course of maturation. A marked hypersensitivity was observed in 7-week-old rats androgenized with 100 μg testosterone propionate. The process of androgenization may include the induction of alterations in the sensitivity of the pituitary to LHRH and probably in the LH synthesizing ability of the pituitary.

抄録全体を表示

The in vivo uptake of ³H-estradiol-17β by the various lymphoid tissues, fat tissue, skeletal muscle and circulating blood of castrated male and female mice of C57BL strain was studied after an intravenous injection of the hormone. In both sexes the highest uptake was by the bone marrow and fat tissue, followed by the spleen, thymus and mesenteric lymph node. The lowest was by the muscle and the blood serum. The lymphoid tissues in the female took up a slightly more amount of radioactivity than those in the male until 1 hr after the injection, but thereafter the uptake was at almost the same level between both sexes. The lymphoid tissues showed a relative and long-term retention of the radioactivity, as compared with that in the muscle and blood serum.
The binding of ³H-estradiol-17β by the lymphoid tissue cytosol and their binding specificity for the hormone were examined in vitro by Sephadex G-100 column analysis. All the tissue cytosols tested contained estradiol-binding component (-s). Among those the thymic cytosol showed to contain the component (-s) which is fairly specific to this hormone. These results suggest that there is a relatively high uptake and retention of estrogen in the lymphoid tissues in which it is bound to cytoplasmic binding component (-s).

抄録全体を表示

In order to investigate a physiological role of 17α-hydroxyprogesterone (17-OHP) during the periovulatory phase, serum levels of LH, FSH, estradiol (E₂), progesterone (P) and 17-OHP were determined by the radioimmunoassay daily through the menstrual cycle and during the treatment for induction of ovulation. In 5 ovulatory women serum, values of these hormones were also examined every 8 hr during the periovulatory phase.
By average data on five cases whose blood samples were taken every eight hr, the first significant rise in 17-OHP began 8 hr after the time of the E2 peak and the initial rise of LH levels, and the 17-OHP levels increased steeply as E2 falled down from the peak. But in 2 cases among 4, 17-OHP values increased 8 hr prior to or simultaneously with the initial rise of LH and in the remaining 2 cases, 17-OHP values started to increase only 16 hr after the initial rise of LH.
These results suggest that the mid cycle 17-OHP peak is not a reflection of increased E₂ synthesis but that 17-OHP may have a physiological role in inducing and/or facilitating LH release. But this role of 17-OHP in LH release should be further investigated.

抄録全体を表示

Continual anovulatory state associating with persistent vaginal cornification (light estrus) was induced by placing 4-day cycling rats under continuous lighting (LL). Uterine cervical stimulation was applied at arbitrary solar hours to light estrous rats showing continual vaginal estrus for more than 2 weeks. The ovulation was induced between 14 and 16hr after the stimulation dissociating entirely with solar hours. Injection of anti-LHRH serum 5min after the stimulation but not later than 20min blocked this ovulation. Ovulation thus induced was always followed by pseudopregnancy with continual leucocytic vaginal smear lasting 10.70 days. The change in concentrations of peripheral serum progesterone during this period was almost similar to that of normal pseudopregnancy except extremely low levels observed at the start and end.
Effectiveness of the cervical stimulation for induction of ovulation in light estrous rats was related to not only the duration of light estrus but also the time after transfer to LL, suggesting that the neural mechanism of ovulation in light estrous rats shifted from that of the spontaneous to reflex ovulators due to the extinction of environmental photic cue.

抄録全体を表示

The effect of bombesin on insulin release from isolated pancreatic islets of rats was examined in vitro. Bombesin, at the doses ranging from 10ng/ml to 1μg/ml, significantly inhibited 16.7mM glucose-induced insulin release, while bombesin had no inhibitory effect on insulin release at 8.3mM and 3.3mM glucose. Moreover, bombesin also suppressed insulin release elicited by 10mM arginine at the doses of 100 ng/ml and 1μg/ml. These results indicate that bombesin has a direct inhibitory action on insulin release.

抄録全体を表示