Pregnant rats were given daily a subcutaneous injection of methyltestosterone for 4 days from the 17th to the 20th day of gestation, and were allowed to be delivered to their offprings (F₁) which were used for the examimation of later reproductive functioning. When observed for 21 weeks after birth, the growth rate of F₁ from methyltestosterone-treated groups was higher than that of F₁ from the control group. The anogenital distance in 50-μg-treated F₁ females started to become significantly longer on the 14th day and in 5μg-treated F₁ females on the 28th day after birth than that in F₁ from the control. The day on which vaginal opening took place in 50% of females was 34.4 days of age in both the control and the 5μg groups, but it delayed until 40.7 days in the 50μg group. Furthermore, persistent estrus was observed after about 90 days of age in the 50μg group. This persistent estrus disappeared by placing these females with males, resulting no pregnancy. In the 5μg group females could be pregnant, but their female fetuses (F₂), when examined on the 21st day of gestation, had significantly shortened the length of the urovaginal septum. The observations show that virilization can be induced in the third generation.

抄録全体を表示

The percentage of labeled cells in the uterine luminal epithelium of cycling mice showed the different zonal distributions at each stage of estrous cycle after cumulative labeling with ³H-thymidine for 36 hr. It was estimated that the proliferating fraction in the epithelium at proestrus, estrus, metestrus, anddiestrus was 100%, 100%, 40% and 5%, respectively. The percentage of labeled cells in the uterine luminal epithelium of cycling mice treated with progesterone remained below 10% level for at least 20 hr after injections of progesterone.
Total labeling was attained in the uterine epithelium of castrated mice by the administration of estradiol-17β. On the other hand, the cell proliferation in the uterine epithelium of castrated mice treated with estradiol and progesterone was markedly suppressed and the percentage of labeled cells remained approximately at 35%. The remaining cell population, however, still showed the mitotic potency when mice received estradiol.
It is suggested from this study that the effect of progesterone is to suppress the epithelial cell proliferation and transfer cells into resting cell fraction which is still evoked to proliferate as the effect of estradiol and that a key factor controlling epithelial proliferation in mouse uterus during the estrous cycle is proliferating fraction rather than cell cycle time.

抄録全体を表示

Adrenaline-induced lipolysis in fat cells was remarkably reduced when the cells were preincubated in a dry ice-aceton bath, but their adenylcyclase and lipase activities were not reduced. In the reconstructed lipid micelles which consisted of lipasedepleted lipid micelles and lipase-containing adipose tissue extract, adrenaline, theophylline and DBcAMP-induced lipolysis was not found when lipase-depleted lipid micelles were preincubated in a dry ice-aceton bath but was found when lipase was preincubated.

抄録全体を表示

The effects of administration of synthetic thyrotropin-releasing hormone (TRH) on circulating growth hormone (GH), prolactin (PRL) and triiodothyronine (T₃) levels of lactating dairy cows, non-lactating dairy heifers, and beef cows were studied. Intravenous administration of 0.1, 1, and 5μg of TRH per kg of body weight (bw) elevated plasma GH and PRL levels of lactating cows within 5min. The plasma GH and PRL levels increased in proportion to the dose of TRH and reached a peak 10 to 30min after TRH injection. Intravenous administration of 1μg of TRH per kg of bw to 7 non-lactating heifers, 14 lactating dairy cows, and 5 non-lactating beef cows elevated plasma GH level to peak values after 15min, the increase rates being 6.9, 5.6, and 3.8times as high as those in the pretreatment levels. The mean maximum value was also in that order. Plasma T₃ levels of non-lactating dairy heifers at pre-and post-injection of TRH were significantly higher than those of lactating cows. The peak values of plasma PRL were obtained between 5 to 30min after TRH administration. The increase rates of lactating dairy cows, heifers, and beef cows were 19.2, 13.9, and 20.9times as high as those in the pretreatment. In contrast to GH and T₃, plasma PRL levels of both pre- and post-injection with TRH in lactating cows and heifers were significantly higher in May than in October, though the increase rates were similar. Plasma PRL levels of lactating dairy cows at pre- and post-injection with TRH were significantly higher than those of non-lactating heifers. Subcutaneous administration of TRH was also effective to increase plasma GH, PRL, and T₃ levels in lactating cows. No significant change of GH or PRL response to TRH was observed after a short-term pretreatment of thyroid hormones.

抄録全体を表示

As a tool with which to detect iodinated compounds in human thyroid specimens, we have reevaluated a nonincineration technique which has so far been employed in the determination of thyroxine-iodine in peripheral blood.
The catalytic action of iodoamino acids in the Ce-As reaction was enhanced by a small amount of Cl₂. On the contrary, a large amount of Cl₂ inhibited the reaction unexpectedly. Among iodide, iodotyrosine and iodothyronine, iodide was the most effective catalyst in the Ce-As reaction and iodothyronine was the least effective one. Protein seemed to inhibit this reaction of thyroglobulin. But the result of iodine content in thyroglobulin by this technique agreed well with that by incineration when measured ¹²⁷I wascorrected by percent activity of dializable part of the total activity of ¹³¹I-thyroglobulin with the same protein concentration, after the NaClo treatment.
The results of human thyroid specimens were as follows: the thyroglobulin content of five normal subjects was 8.0±1.5% of wet thyroid weight. That of Hashimoto's disease was significantly decreased which seemed compatible with the decrease in iodine content of thyroglobulin, whereas thyroglobulin content of Graves disease treated with 1-methyl, 2-mercaptoimidazole followed by a large dose of iodide was well preserved in spite of a lower degree of iodination of thyroglobulin. As for the distribution of iodoamino acids-iodine in normal thyroid, T₄ was 20.5±0.7%.
This technique ultimately looks promising as a tool with which to study intrathyroidal iodine metabolism in human.

抄録全体を表示

The determination of chromogranine released in exocytosis as well as of the catecholamines released from the adrenal medulla should greatly contribute not only to unraveling the mechanism of exocytosis but also to clinically diagnosing pheochromocytoma. The determination of chromogranine, however, has not been amply studied as yet.
In the first place, the catecholamine-storing vesicle-rich fraction was collected from the pig adrenal medulla by the density gradienter. In order to lyse these cell particles, they were first frozen with cold methanol, then thawed, and centrifuged. The supernatant was developed by DEAE chromatography to collect only the peak fraction, from which chromogranine was isolated. Rabbits were then injected with this chromogranine to obtain the anti-chromogranine antiserum. The successful immunization of the rabbits was demonstrated by immunodiffusion on the Ouchterlony plate.
The anti-pig chromogranine antiserum was demonstrated to be common in antigenicities with the human pheochromocytoma extract; and a serological method of chromogranine assay was then developed. For the preparation of the sensitized sheep red blood cells, the sheep red blood cells were first made to bind to the pig chromogranine by means of treating them with a formaldehyde solution and tannic acid. For the assay of the pheochromocytoma extract for chromogranine 25μl of the extract were added to two-fold dilution series of 25μl of the anti-chromogranine antiserum, then 25μl of the sensitized red blood cells was added. The dilution number of the antiserum that completely inhibited hemagglutination reaction, that is, inhibition titer, was defined as the level of chromogranine. This method demonstrated the occurrence of large amounts of catecholamines in the resected tissue extract and also of chromogranine at the 1: 8 inhibition titer.

抄録全体を表示

Acetylation of porcine thyroglobulin with N-acetyl imidazole was performed at various temperatures in the presence and absence of urea. In the medium without urea, the number of O-acetylated iodoamino acid residues formed was constantly 15 above 10°C (originating from all diiodotyrosyl and a few of monoiodotyrosyl residues), while the number of O-acetyl tyrosyl residues increased gradually from 15 at 0°C to a maximum of 70 at 70°C. All (about 25) iodoamino acid residues were acetylated at 20°C in 2M urea, while the presence of 8M urea was necessary to acetylate all tyrosyl residues at 20°C. Experiments on the nitration of thyroglobulin with tetranitromethane showed that diiodotyrosyl and thyroxyl residues were easily nitrated even at low temperatures and the low ratio of the reagent to the protein, while tyrosyl residues consisted of three groups: the first group (about 14%) which was very easily nitrated even at 0°C and the low ratio of the reagent to the protein, the second group (about 45%) which was nitrated depending on temperature and the molar ratio of the reagent, the remaining which was definitely unreactive even under extreme conditions. In addition, the ionization of tyrosyl and iodoamino acid residues was studied by spectrophotometric titration at various temperatures in the presence and absence of 8M urea. It was found that diiodotyrosyl and thyroxyl residues did not change very much with respect to ionization behaviour by the addition of urea, in contrast to clear dependency of tyrosyl residues on urea. Based on these observations, the location of these residues and the structural change of the protein with temperature are discussed.

抄録全体を表示

The effect of intravenous infusion of cytidine diphosphate choline (CDP-choline) on the serum levels of growth hormone (GH) and prolactin (PRL) was studied in six normal adult male subjets. Serum GH levels increased and reached a maximum at 60-90min after the initiation of infusion in all subjects examined. The mean peak value of GH in six subjects was 10.0±2.1 (mean±SE) ng/ml, which was significantly higher than the basal level (p<0.01). In four subjects, serum PRL levels decreased from 10-24ng/ml to less than 7.2 ng/ml at 60-120 min, while in the other two no significant change was observed. These results indicate that CDP-choline affects GH and PRL secretion from the anterior pituitary.

抄録全体を表示

In order to elucidate the positive feedback mechanism of estrogen on gonadotropin release in women, the responses of plasma LH and FSH to the constant infusion of estradiol-17β for a prolonged period were studied. The infusion was initiated on various days of the follicular phase and maintained for 36-66hr at a constant rate of 500 or 1, 000μg/24 hr. When the stimulus of estradiol was sustained for more than 30hr in the women of the middle or late follicular phase, a positive feedback effect to elicit gonadotropin surges was observed during the maintenance of the infusion. In contrast, the stimulus of estrogen was ineffective in the early follicular phase, even if sustained for a longer period up to 66 hr. Gonadotropin levels, also, increased after the end of infusion. The magnitude of the responses, however, was much smaller, as compared to spontaneous preovulatory gonadotropin surges. In all cases, the effect of estradiol was greater for LH than for FSH. It is suggested that: 1) Preovulatory gonadotropin surges are triggered by estrogen increments rather than the withdrawal of the negative feedback effect of estrogen. 2) Low levels of estrogen for a certain period of the early follicular phase may play an important role in priming the control system which responds to the positive feedback effect of estrogen.

抄録全体を表示

During two weeks prepartum, one hundred mg of 2-Br-α-ergocryptine (CB154), a potent prolactin inhibitor, was subcutaneously administered to dairy cows 8 to 10 times. Simultaneous injections of an antiserum to bovine prolactin around parturition were also given to a CB154-administered cow. The serum prolactin (PRL) level decreased to less than 2ng/ml immediately after the commencement of CB154 injection, and the low level continued until calving. PRL surge near parturition which usually emerged in normal calving, completely disappeared. The low serum PRL level continued till at least two weeks after calving. No reduction of serum growth hormone and triiodothyronine levels was detected. Lactogenesis was more or less suppressed by CB154 administration. The mean milk production in three cows during a week postpartum was 58.5% of that of the previous lactation. It took 30 to 50 days to attain the milk yield of the previous lactation. In the cow administered with CB154 and an antiserum to bovine PRL simultaneously, the milk production reduced to 43.7% of that of the previous lactation. The milk production was not achieved to that of the previous lactation even on the 50th day after calving. The concentrations of total milk protein, IgG, and β-lactoglobulin in colostrum and milk from the cows treated with CB154 were significantly higher than those from the control cows. On the contrary, the concentration of a-lactalbumin in colostrum from the cows given CB154 was 40% of that the control cows (p<0.001). The concentrations of lactose and a-lactalbumin on the 6th day postpartum were also significantly lower than those of the control cows. These results indicate that the suppression of PRL secretion around parturition after CB154 treatment induces the reduction of syntheses of a-lactalbumin, lactose and the depression of milk production during lactogenesis.

抄録全体を表示

The process of development of thyroidectomy (TX) cells from the so-called thyrotrophs (the H-type cells by Yoshimura et al., 1977) was electron-microscopically investigated at intervals of 12 hr, 1, 3, 5, 7 and 14 days after TX. Cytological changes of the II-type cells vary from cell to cell even at the same intervals after TX. From 12 hr to 5 days, the II-type cells are characterized by the deprivation of secretory granules and the enlargement of cell size. When extensively degranulated, the II-type cells appear as vesiculated cells with a round or oval shape, resembling the LH-gonadotrophs (the III-type cells). The frequent detection of III- and IV-type cells (FSH-gonadotrophs) is in striking contrast with the infrequent detection of IItype cells within 12 hr and 1 day. Some pre-existed IV-type cells show retrogressive signs after TX. Some other IV-type cells are moderately granulated, at 1, 3 and 5 days, followed by the deprivation of the stored secretory granules, resulting in the vesiculated cells. These cells begin to appear at 3 days and increase in number at 5 and 7 days, despite the individual disparity in development. They may be the immature TX-cells characterized by the closure of Golgi lamellae, and by granules of low density in the small, irregularly shaped cisternae. They gradually increase in dimensions with the lapse of time. Degranulation and accumulation of large cisternae with progressive sedimentation of intracisternal granules may account for the maturation of TX-cells. By 14 days the maximal diameter of the mature TX-cells becomes 3-4 times as large as that of an acidophil. From the present observations, it is tentatively concluded that TX cells may not directly develop from the II-type cells, but indirectly through the III- or IV-type cells; and that the TX-cells may not be hyperfunctioning thyrotrophs, but rather dysfunctioning basophils.

抄録全体を表示

Quantitative changes of pituitary basophils were investigated by the method of Chalkley, together with radioimmunoassays of serum TSH, LH and FSH concentrations, in rats during the short interval after thyroidectomy (TX)(3, 6, 12 hr, 1, 3, 5 and 7 days). The irregularly shaped or elongated II-type cells (classical thyrotrophs), which are stained intensively with thionin, immediately decrease in number below the normal value (2.7±0.7%), to 0.6±0.2% at 12 hr and 0.3±0.1% at 7 days. The intermediate cells (II/III-type cells) can be easily distinguished, by their staining properties and shape, from the II-type cells and III-type cells (classical LH-gonadotrophs) during this time interval. The II/III-type cells are enlarged polygonal cells whose central area stains with PAS and whose peripheral area shows an affinity for thionin. They gradually increase in number after the first day. The total number of all kinds of the PAS-positive cells tends to rapidly increase after TX and reaches the highest value (12.3±0.8%) after as early as 12 hr. They are distinguishable as oval III-type cells stained violet and large spherical or polygonal IV-type cells stained red. However, the values returns to normal (9.7±0.5%) by 7 days. The total of all kinds of basophils (II-, II/III-, III-, III/IV- and IV-type cells), however, is not altered but remain balanced through the entire time. Serum TSH concentrations rise at 3 hr and fall thereafter, but rise again at 5 days (230.5±16.7ng/ml), the latter being equivalent to twice the normal value (122.5±8.7ng/ml). Serum FSH concentrations tend to be slightly reduced, but not profoundly, through the entire time course after TX. Serum LH concentrations quickly and conspicuously 4crease after the operation, reaching the lowest value (0.18±0.06ng/ml), equivalent to approximately 1/4 of the normal value (1.42±0.12ng/ml), within one day. It has been corroborated by the present results of cell counts and radioimmunoassays that, following TX, the II-type cells may transform morphokinetically into the III- and IV-type cells, supporting a working hypothesis as to the secretory cycle of the basophil proposed by Yoshimura et al.(1977).

抄録全体を表示

Nα-Tyrosyl-somatostatin was synthesized and proved to be homogeneous. Radioiodination of this tyrosine-containing somatostatin analogue by either the lactoperoxidase method or the chloramine T method led to the formation of crude iodinated compound, which was purified by ion exchange chromatography on CM-Sephadex C-25 using a linear ammonium acetate buffer gradient. This purification process was found to be satisfactorily reproducible and suitable for the preparation of ¹²⁵IN^α-tyrosyl-somatostatin. Using the purified ¹²⁵I-somatostatin analogue, radioimmunoassay for somatostatin was performed and the assay system was proved to be sensitive and specific for somatostatin. Immunoassays of hot-water extracts of porcine and tupaia brain, pancreas, stomach and various regions of the intestine in the system revealed that those tissues contained immunoreactive somatostatin at various concentrations. Of the results, it was remarkable that somatostatin immunoreactivity was found in the ileum, middle colon and rectum in both animals, although the concentrations were lower when compared with those in the stomach, duodenum and jejunum.

抄録全体を表示

The thyroid lobes excised from one-day-old or 13-day-old chickens were incubated with or without TSH, and cAMP in the medium was determined. TSH induced the release of cAMP from thyroid lobes, resulting in the increase of cAMP concentration in the incubating medium. The release of cAMP into the incubating media in the presence of TSH from the thyroids of the chickens which were pretreated with TS neonatally was more marked as compared to that from the thyroids of the control chickens. The light and electron microscopic examination of the thyroid lobes incubated with TSH showed that the morphological changes such as colloid droplets formation and enlargement of endoplasmic reticulum were induced.

抄録全体を表示