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Biomedical subjects

T Aono

Publications and source records attributed to T Aono.

At least 361 records · Page 20Linked to original sources
PubMed1978

The time course change after castration in short-loop negative feedback control of LH by HCG in women.

The time course of change in the suppressive effect of human chorionic gonadotrophin (HCG) on luteinizing hormone (LH) and/or LH-beta following castration was studied by a specific LH-beta radioimmunoassay. At 14-50 days after castration 8 women were given 10 000 IU of HCG in a single intramuscular injection (group 1), 5 women were given 2000 IU of HCG in the same way (group 2), and 5 were injected with saline as controls (group 5). In addition, 5 women 6-15 months (group 3) and 7 women 3-8 years (group 4) after castration were given 10 000 IU of HCG. The serum concentrations of HCG in groups 1, 2, 3 and 4 reached peak levels of 209.4, 44.1, 210.6 and 238.6 uU/ml, respectively, 4 h after the HCG injection. The serum LH concentration in group 1 was reduced significantly (P less than 0.01) by HCG administration, but the reductions in the LH levels in groups 2, 3 and 4 after HCG injection were not significantly different from that of the controls. These findings suggest that the threshold of the short-loop negative feedback control of LH in women changes with time after castration.

Adult↗
PubMed1978

Pituitary LH response to LHRH during puerperium.

Forty puerperal women and 15 normally menstruating women used as controls were given 100 microgram of synthetic luteinizing hormone releasing hormone (LHRH) in a single intravenous injection. Serum concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and human chorionic gonadotropin (hCG) were measured by a specific radioimmunoassay (RIA). The LH-beta RIA method, which is unaffected by hCG at sample levels as high as 500 IU/ml, was used to determine serum LH levels. Basal serum FSH and LH levels determined immediately after delivery were lower than those in the follicular and luteal phases during the normal menstrual cycle. These levels rose gradually after delivery, and finally returned to normal levels during the 16th to 25th days of the puerperal period. Small, but significant, LH response to LHRH was observed 6-10 days after delivery, and gradually returned to normal thereafter, though the response was poor during the first 35 days of the puerperal period when compared with that of the controls. On the other hand, no FSH response to LHRH was observed until 16-25 days after delivery, when the response was greater than that of the controls.

Adult↗
PubMed1977

Primary hypothyroidism and galactorrhea.

Ten of 16 women with primary hypothyroidism and high thyrotropin (TSH) concentrations had high serum prolactin (PRL) concentrations. A positive correlation was observed between the basal TSH and PRL levels in the hypothyroid patients. Five of these patients complained of persistent galactorrhea after delivery. After treatment with triiodothyronine (T3), the elevated TSH and PRL levels fell to within normal ranges, and the galactorrhea disappeared. It is suggested that the elevated serum PRL levels of patients with primary hypothyroidism are mediated by feedback-induced thyrotropin-releasing hormone (TRH) secretion or an enhanced response to endogenous TRH, and that the combination of delivery and the PRL excess may induce persistent galactorrhea in patients with primary hypothyroidism.

Adult↗
PubMed1977

Pregnancy following thyroid hormone treatment in a patient with amenorrhea-galactorrhea due to primary hypothyroidism.

A 32-year-old female with amenorrhea-galactorrhea due to primary hypothyroidism was treated with thyroid hormones, and serum levels of thyrotropin (TSH), prolactin (PRL), triiodothyronine (T3), thyroxin (T4), and T3 resin sponge uptake (RT3U) were measured throughout the course of treatment. The elevated serum levels of TSH and PRL fell into the normal range following T3 treatment. Subsequently, the menstrual cycle was restored within 1 month, and galactorrhea completely ceased and conception was achieved within 3 months. Desiccated thyroid was administered during pregnancy, and the patient gave birth to a female infant. Impaired secretion of PRL during pregnancy and poor milk secretion with blunted response of PRL to the suckling stimulus during the puerperium were noted.

Adolescent↗
PubMed1977

Effect of triiodothyronine treatment on prolactin secretion in patients with amenorrhea-galactorrhea.

In order to determine the role of thyroid hormone in prolactin (PRL) secretion in patients with amenorrhea-galactorrhae, PRL response to 500 mug of iv thyrotropin-releasing hormone (TRH) was studied before and after the administration of triiodothyronine (T3) in 10 patients with amenorrhea-galactorrhea. Seven of these patients were euthyroid and the other 3 had hypothyroidism. The patients in the euthyroid group received 50 mug of T3 daily for 7 days and 75 mug q.d. for the ensuing 14 days. The hypothyroid patients received T3 at progressively increasing doses from 10 mug q.d. to 75 mug q.d. during 34 to 68 days. In the initial test, the elevated basal levels of PRL, 61.9 +/- 9.8 ng/ml (Mean +/- SE) exhibited a slight but insignificant net increase (7.7 +/- 2.1 ng/ml) after TRH injection in the euthyroid group. However, a marked response to TRH with a net increase of 147.2 +/- 26.3 ng/ml from the basal level of 47.3 +/- 11.2 ng/ml was observed in the hypothyroid patients. After treatment with T3, both the basal level (56.9 +/- 8.3 ng/ml) and the net increase (9.9 +/- 3.6 ng/ml) of PRL following TRH stimulation remained virtually unchanged in the euthyroid group. The hypothyroid group, in contrast, displayed a significant depression of both the basal level (26.1 +/- 13.0 ng/ml) and the net increase (33.8 +/- 6.5 ng/ml) of PRL to TRH stimulation. The diminution of the basal levels and responses of thyroid-stimulating hormone (TSH) to TRH stimulation was observed in all cases of both groups. These results suggest that the level of thyroid hormone has little pathogenic role in PRL secretion in euthyroid patients with amenorrhea-galactorrhea, in contrast to its marked effect in hypothyroid patients with amenorrhea-galactorrhea.

Adult↗
PubMed1977

LH concentrations in human maternal and cord serum.

Maternal blood and umbilical cord venous blood were collected immediately after delivery in 32 subjects who had completed normal birth during the 38 to 41 weeks of pregnancy, and the concentrations of human chorionic gonadotropin (hCG), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were determined by radioimmunoassay (RIA). The specific LH RIA utilized for the measurement of LH is unaffected by hCG at sample levels as high as 500 IU/ml. HCG concentrations were 10,370 +/- 1,480 mIU/ml (mean +/- SE) in mother's serum and 34.5 +/- 5.2 ml in cord serum, while LH concentrations were 0.729 +/- 0.055 and 0.438 +/- 0.033 ng/ml, respectively. The concentration of all 3 gonadotropins in maternal serum was greater than cord serum and the ratio was markedly high with 302:1 for hCG, while the ratio was smaller for LH, being 1.7:1, while that for FSH was 4.2:1. There was no difference in the levels of LH and FSH in relation to the sex of the fetus.

Adult↗
PubMed1977

Responses of serum gonadotrophins to LH-releasing hormone and oestrogens in Japanese women with polycystic ovaries.

In order to define the abnormality in gonadotrophin secretion in Japanese women with polycystic ovaries (PCO) who rarely show virilization and markedly enlarged ovaries, basal levels of LH and FSH, and responses of serum gonadotrophins to LH-releasing hormone (LH-RH) or oestrogens were determined by radioimmunoassay. Eleven patients with PCO diagnosed by laparotomy or laparoscopy and 30 normal women in the follicular phase were studied. The mean (+/- SD) basal level of LH was significantly higher in patients with PCO than in normal controls (PCO 28.6 +/- 2.4 vs. normal 10.9 +/- 3.0 mIU/ml), while the mean FSH level in PCO patients was not significantly different from that in the normal controls (9.7 +/- 0.7 vs. 11.4 +/- 2.6 mIU/ml). The mean LH/FSH ratio in PCO patients was significantly higher than that in normal controls (3.2 +/- 0.9 vs. 1.0 +/- 0.3). Exaggerated response of LH to LH-RH was observed in PCO patients, while the FSH response was comparable with the normal controls. Ten out of 11 patients with PCO showed LH release exceeding the basal level after bolus iv injection of 20 mg conjugated oestrogens (Premarin), and virtually the same mean net increase in LH from the basal level was obtained in both PCO patients and normal controls. Since the abnormalities in gonadotrophin secretion in Japanese women with PCO are not different from those reported in patients with PCO in Europe and USA, it seems likely that lower incidence of markedly enlarged ovaries and virilization in Japanese patients may be caused by the difference in ovarian response to gonadotrophin.

Adult↗
PubMed1977

Pituitary responses in LH secretion to LHRH during pregnancy.

Thirty-six pregnant women and 15 normally menstruating women were each given 100 microng of synthetic luteinizing hormone releasing hormone (LHRH) by a single intravenous injection. Human chorionic gonadotropin (hCG), luteinizing hormone (LH), and follicle stimulating hormone (FSH) levels were determined by specific radioimmunoassay (RIA) technics. For the determination of the serum LH levels, the LHbeta-RIA method, which is unaffected by hCG at sample levels as high as 500 IU/ml, was used. Serum concentrations of LH and FSH were lower in pregnant women than in the normal women in the follicular and luteal phases. While the release of LH was observed in pregnant women following the administration of LHRH, the average net increase was less than that seen in both the follicular and luteal phases. During pregnancy, there was a progressive decrease in the LH response to LHRH, but no release of FSH.

Adult↗