We studied plasma vasopressin concentrations during hypertonic saline infusions in 5 men with hypogonadism and 10 normal men to investigate the effect of gonadal steroid on hypothalamo-neurohypophyseal function. All the subjects received the infusion of 5% saline, and plasma vasopressin concentrations were determined by radioimmunoassay (RIA). Three of the 5 men were patients with isolated hypogonadotropic hypogonadism (IHH) and the other wo were patients with Klinefelter's syndrome. None of them had any symptoms of diabetes insipidus. Although there was no difference between basal plasma osmolality in the patients and the normal subjects (287.2±2.1 vs. 285.3±1.8 mmol/kg), the basal level of plasma vasopressin in the patients was lower than that in the normal subjects (0.62±0.17 vs. 1.36±0.15pg/ml, P<0.05). Hypertonic saline infusion revealed varying degrees of subnormal vasopressin responses in the patients except one patient with Klinefelter's syndrome. The mean vasopressin response to osmotic stimuli (Δ plasma vasopressin / Δ plasma osmolality) in the 5 patients was lower than in the normal subjects (0.04±0.01 vs. 0.16±0.02, P<0.05). Three patients with IHH and one patient with Klinefelter's syndrome were re-examined after pulsatile gonadotropin-releasing hormone (GnRH) infusion or testosterone enanthate i.m. injection. After the treatment with testosterone or GnRH, the response of plasma vasopressin to hypertonic saline infusion was normalized in three patients who had subnormal vasopressin response before treatment (Δ plasma vasopressin / Δ plasma osmolality: 0.04±0.01 vs. 0.09±0.01, P<0.05). These results suggest that testosterone improves the subnormal vasopressin response to osmotic stimuli in men with hypogonadism.

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We synthesized four peptides (HTg-1, 1-10; HTg-2, 2547-2558; HTg-4, 2592-2603 and HTg-6, 2737-2748) and two peptides (HTg-3, 2582-2591 and HTg-5, 2687-2694) with or without hormonogenic acceptor tyrosine of human thyroglobulin (hTg). They were iodinated with ¹²⁷I or ¹²⁵I. ¹²⁷I-labeled peptides were tested for their ability to displace ¹²⁵I-T₄ binding to thyroid hormone autoantibodies (THAA) in two cases of Graves' disease and to a murine anti-hTg monoclonal antibody with anti-T₄ activity (mAb). ¹²⁵I-labeled peptides were tested for the direct binding to the aforementioned antibodies. None of the peptides displaced ¹²⁵I-T₄ binding to THAA or to a mAb, or exhibited increased binding to THAA and to a mAb. ¹²⁵I-T₄ binding to a mAb was equally displaced by hTgs obtained from a normal thyroid gland (NTg) and a case of Hürthle cell adenoma with undetectable iodine content (CTg). ¹²⁵I-T₄ binding to serum gamma globulin in each patient's serum was completely displaced by NTg, but CTg displaced ¹²⁵I-T₄ binding 2% and 5% in Case 1 and Case 2, respectively. It was speculated that the mAb recognizes a topological epitope around the hormonogenic site of hTg, while that of THAA in our two cases recognizes only T₄ or an iodine dependent topological epitope(s) of hTg.

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Cytosolic 3, 5, 3'-triiodo-L-thyronine (T₃)-binding protein (CTBP) plays an important role in the regulation of intracellular T₃ translocation from cytoplasm to the nuclear T₃ receptor. We examined whether the CTBP activity could be induced by T₃ or not in cultured hepatocytes prepared from thyroidectomized rats. CTBP activity was not detected in primary cultured hepatocytes from thyroidectomized rats. However, the protein was induced by the addition of T₃ to the culture medium. The increase in the activity of CTBP was time dependent and the maximal level was obtained by 48h in the presence of 300nM T₃. CTBP activity was also increased by retinol (35μM) or by 1, 25-(OH)₂-vitamin D₃ (10nM). On the other hand, the activity of malic enzyme (ME) was induced by the addition of T₃ to the culture medium. The maximal activity of ME was obtained by 48h in the presence of 300nM T₃. The increase in ME activity was also induced by retinol or 1, 25-(OH)₂-vitamin D₃. These results suggested that not only ME activity but also CTBP activity is induced by T₃. Further, retinol and vitamin D₃ have similar effects on the induction of CTBP activity and ME activity.

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We investigated whether the inhibition of placental T₄ 5-deiodinase (5-D) activity would decrease the amniotic fluid (AF) concentration of rT3. Iopanoic acid (TOP) was used to inhibit placental T₄ 5-D activity. From gestation days 14 to 17, a group of rats received IOP (10mg/100g bw/day, sc) once daily in experiment (exp) 1, and received it (40mg/100g bw/day) four times daily in exp 2. In exp 2, control dams received propylthiouracil (PTU; 2mg/100g bw/day) instead of IOP. Methimazole and T₄ were also given to all dams in exp 1 and 2. On day 17 of gestation, we collected the liver, placenta, blood, and AF of each animal. In the IOP-treated group in both experiments, the serum T₄ concentration was significantly increased. Hepatic T₄ 5'-deiodinase activity was significantly decreased by eithe r PTU or IOP administration. In both experiments placental T₄ 5-D activity was significantly decreased in the IOP-treated group. The concentration of rT₃ in AF was significantly decreased in the IOP-treated group in exp 2 (1.71 vs. 0.75nmol/l, P<0.01) despite a higher serum T₄ concentration. There was a significant positive correlation between placental T₄ 5-D activity and the concentration of rT₃ in AF in exp 2 (r=0.62, P<0.05). These observations indicate that the inhibition of placental T₄ 5-D activity decreases the concentration of rT₃ in rat AF, and that placental T₄ 5-D and the T₄ concentration in maternal serum plays important roles in maintaining the concentration of rT₃ in rat AF.

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In the ovary, insulin and insulin-like growth factor-I (IGF-I) act synergistically with FSH to augment estrogen production by granulosa cells and with LH to augment androgen production by thecal stromal cells. It is also evident that insulin resistance is common in patients with polycystic ovary syndrome (PCO). Thus, in the present study we investigated the expression of insulin and IGF-I receptors in PCO ovaries and compared them with those in normal ovaries. Ovarian tissues were obtained from four PCO patients undergoing wedge resection, and from six patients who underwent radical hysterectomy. Immunohistochemical staining for insulin and IGF-I receptors was performed by avidin/biotin immunoperoxidase techniques. In normal ovaries, the expression of insulin and IGF-I receptors in follicular compartment became apparent in the preantral follicle stage and augmented with the follicular growth, while the stromal cells, regardless of the follicle stage, possessed insulin and IGF-I receptors. In PCO ovaries associated with hyperinsulinemia, no expression of insulin receptors was detected in granulosa or thecal stromal cells, while IGF-I receptor expression increased in thecal stromal cells but decreased in granulosa cells compared to those in normal ovaries. However, in PCO ovaries from patients without hyperinsulinemia, insulin receptor expression was apparent in both granulosa and thecal stromal cells, with a similar intensity to that observed in normal ovaries, while IGF-I receptor expression was negligible in granulosa cells but sustained in thecal stromal cells. These findings suggest that decreased expression of insulin receptors in PCO ovaries associated with hyperinsulinemia may be secondary to receptor down regulation, whereas defective expression in granulosa cells along with elevated or persisted expression in thecal stromal cells of IGF-I receptors may be common in PCO ovaries and contribute to the endocrine profiles of PCO in which varying degrees of hyperandrogenism is a predominant feature.

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An inhibitory effect of TZP-4238, a newly synthesized antiandrogen, on the growth of Dunning R3327 rat prostatic tumor was studied and compared with that of chlormadinone acetate (CMA). TZP-4238 markedly suppressed the growth of R3327 tumor. The inhibitory effect of TZP-4238 on the tumor was more potent than that on the prostate. While the inhibitory effect of TZP-4238 on the weight of the ventral prostate was about 6 times as great as that of CMA, the suppressive effect of TZP-4238 on tumor weight was about 40times as great as that of CMA. Serum levels of testosterone and dihydrotestosterone showed no obvious changes after the administration of either TZP-4238 or CMA. The inhibitory effect of TZP-4238 on the growth of R3327 tumor indicated the application of the compound to human prostatic cancer.

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A fifty-year-old woman was admitted to our hospital because of generalized edema, progressive symptoms of fatigue and weakness of ten years' duration. After an uneventful third delivery, 24 years before admission, she could not lactate and developed oligomenorrhea and then amenorrhea. Laboratory evaluation revealed panhypopituitarism and pituitary cell antibodies were positive. Both CT scans and MR images showed empty sella. This case is postpartum hypopituitarism without a preceding history of excessive bleeding and may be autoimmune hypophysitis.

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In order to examine the existence and level of androgen receptor messenger ribonucleic acid (ARmRNA) in the rat brain, reverse transcription-polymerase chain reaction (RT-PCR)-Southern blot analysis was carried out. Total RNA extracted from each tissue was reverse transcribed, followed by PCR with two oligonucleotide primers specific for a part (458bp) of the androgen binding domain of the rat ARcDNA. It was confirmed by direct nucleotide sequencing that the amplified fragment corresponded to part of the rat ARcDNA. To detect and quantify the amplified fragments, a Southern blot analysis was carried out. The levels of amplified fragments were calculated from the standard curve obtained from graded diluted adrenal total RNAs. In the present study, it was revealed that the RT-PCR-Southern blot analysis possessed a high-degree of sensitivity and allowed the quantitative estimation of mRNA. With this method, amplified fragments were obtained from all five brain regions examined. The results indicate that ARmRNA is widely distributed in the whole brain. Moreover, since the ARmRNA level roughly paralleled the AR protein level, it seems that the AR protein level in the brain may be primarily regulated by the ARmRNA level.

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Follistatin-free activin and inhibin levels were measured in the culture medium of porcine granulosa cells by a competitive protein binding assay and N-fragment RIA, respectively. Cultures were maintained for 6 days in MEM containing 10% fetal calf serum. FSH and HCG (1-1, 000 IU/L) were added on day 2 to cultures containing 1×10⁵cells/ml and the medium was changed every 2 days. Granulosa cells secreted a large amount of progesterone, which indicated their luteinization. Activin and Inhibin were both secreted throughout the 6 day culture period. Both of them increased equally in response to FSH and HCG in a dose-dependent manner on day 4, but their responses became discrepant on day 6, when the activin response decreased while the response of inhibin increased. This study demonstrated that cultured porcine granulosa cells secrete both activin and inhibin under the control of FSH and LH. The activin response was lost before that of inhibin, suggesting the role of activin at an earlier stage of luteinization.

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We have studied the nature and characteristics of cholesterol esterase (CEase) in human adrenal adenoma and hyperplasia tissues showing Cushing's syndrome, comparing with those in normal tissue. Each tissue demonstrated that two pH optima were found at around 4.5 and 8.0. The results of a subcellular distribution study show that acid and alkaline CEase are mainly located in lysosomes and microsomes, respectively. Our previous data suggested that phosphatidylcholine which was sonicated with cholesteryl oleate as a substrate may play a crucial role in the regulation of CEase in rat adrenal. The effect of phosphatidylcholine was therefore investigated in the present study. Acid CEase in normal tissue was increased in a dose-dependent manner by phosphatidylcholine, but not in the adenoma or hyperplasia tissues. None of those tissues showed any enhancement in alkaline CEase activity when phosphatidylcholine was added to the substrates. It is therefore suggested that the mechanism of regulation of CEase among three different kinds of human adrenals may be different from the data for the effect of phosphatidylcholine. Basal activity of acid CEase in adenoma and hyperplasia was significantly higher than that in normal tissue, and also that of alkaline CEase in hyperplasia tissue was significantly higher than that in normal tissue. Thus it is suggested that such an adrenocortical disorder as Cushing's syndrome due to adenoma and diffuse hyperplasia of the adrenal cortex may posscss the nature and characteristics of autonomy of steroidogenesis which seems to be induced by the active metabolism of cholesterol, when compared with normal tissue.

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Administration of monosodium L-glutamate (MSG) to neonatal mice produces a hypothalamic syndrome consisting of stunted growth and later development of obesity. We assayed plasma insulin (IRI), thyroxine (T4) and insulin-like growth factor-I (IGF-I) to investigate their roles in the growth of the mice. Two mg/g body weight of MSG was injected into newborn male mice daily for five successive days after birth. Plasma IRI levels were increased on and after 8 weeks of age in MSG-treated mice. There was no significant difference between the plasma T4 levels in MSG-treated mice and those in controls at any age studied. In contrast to this, plasma IGF-I levels in MSG-treated mice were reduced at one week and after. These results suggest that a decreased plasma IGF-I level contributes to the retarded linear growth which develops soon after the administration of MSG, and hyperinsulinemia contributes to the later development of obesity in MSG-treated mice.

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We report a case of a 58-year-old man with adrenal medullary hyperplasia associated with cortisol producing adenoma. Preoperative examination showed both adrenocortical and adrenomedullary hyperfunction. No Cushingoid sign was present and pheochromocytoma-like symptoms were predominant. Abdominal computarized tomography revealed a left adrenal tumor stained by contrast medium. Histologically, the adrenal tumor was found to be a cortical adenoma, and medullary hyperplasia was observed in the remaining parenchyma.

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A case of isolated ACTH deficiency accompanying transient primary hypothyroidism was reported along with a review of literature on isolated ACTH deficiency in Japan with special reference to its association with thyroid function. Our case, a 56-year-old woman, developed somnolence and hypoglycemia due to isolated ACTH deficiency. She also had the features of hypothyroidism, namely mounding phenomenon, muscle rigidity, increased plasma myogenic enzymes and cold intolerance. Both free T₃ and free T₄ were decreased, and basal as well as TRH-stimulated TSH levels were abnormally high. Plasma thyroglobulin was increased and no anti-thyroid antibodies were detected. All thyroid related physical and biochemical abnormalities disappeared after hydrocortisone replacement. A review of the literature on 103 cases disclosed that more than half the cases with isolated ACTH deficiency had a high plasma level of TSH, basal and/or TRH-induced, while the antithyroid antibodies were reported to be positive in only 13 cases. In more than 70% of such cases, the abnormality in the pituitary-thyroid axis was transient and was reversed by glucocorticoid replacement. Our case and cases in the literature indicate that the interference of thyroid hormone synthesis and/or secretion by glucocorticoid deficiency per se is the major cause of thyroid dysfunction rather than associated autoimmune thyroid disease.

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The effect of a synthetic steroidal anti-androgen, TZP-4238, on steroid-induced rat prostatic hyperplasia was investigated. Male Wistar rats were divided into four experimental groups. Group 1 consisted of intact controls. The other animals were castrated. The castrated animals were treated for 7 weeks with 1) testosterone 1mg/head plus 17β-estradiol (E₂) 0.01mg/head (Group 2), 2) testosterone plus E₂+TZP-4238 8mg/kg (Group 3) and 3) testosterone plus E₂+chlormadinone acetate (CMA) 20mg/kg (Group 4). TZP-4238 and CMA were administered orally for 4 weeks after 3 weeks treatment with testosterone plus E₂. In group 2, glandular hyperplasia of the prostate was clearly observed, and the number of bromo-deoxyuridine (BrdU)-positive cells showed a significant increase. In contrast, combined treatment with TZP-4238 (Group 3) or CMA (Group 4) produced marked atrophy of the glandular epithelium, and the number of BrdU-positive cells were remarkably decreased compared with Group 2. In addition, the localization of glutathione-peroxidase (GSH-PO) which effectively reduces the lipid peroxides in the glandular epithelial cells was markedly decreased. Furthermore, nuclear immunostaining of androgen receptor was remarkably decreased after combined treatment with TZP-4238 or CMA. Our data indicate that TZP-4238 is a potent steroidal androgen receptor antagonist for the prevention of rat prostatic growth in the steroid-induced prostatic hyperplasia model.

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