The effect of methimazole (MMI) and 2-mercaptoethanol (ME) on Itransport was studied using phospholipid vesicles (P-vesicles) made from porcine thyroid plasma membranes and soybean phospholipids by sonication.
1. When buffer solutions contained either 1mM MMI or 2mM ME, I^-uptake by P-vesicles in the presence of external Na⁺ was apparently higher than that in the absence of external Na⁺. Na⁺-dependent I^- uptake was inhibited by both C10₄^- and SCN^- added externally.
2. When PM was treated with 4mM N-ethylmaleimide prior topreparation of P-vesicles, the activity of Na⁺-dependent I^- transport was completely lost even when P-vesicles were incubated in the presence of ME.
3. When neither MMI nor ME was added to buffers, I^- uptake in the presence of external Na⁺ was not at all higher than that in the absence of external Na⁺. In these instances, however, I^- uptake was much higher compared than the baseline uptake in the presence of MMI or ME, and was inhibited by external SCN^- and not by C10₄^- without relation to external Na⁺.
These data indicate that MMI or ME has two distinct effects on our model system of I^- transport. The one is preservation of the Na⁺-dependent I^- transport acitivity by protecting a sulfhydryl group, and the other is reduction of nonspecific I^- binding to P-vesicles. In addition, C10₄^- is a more specific inhibitor of thyroid I^- transport than SCN^-, when non-specific I^- oxidation is imperfectly prevented.

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We investigated the response to immunoglobulin G-secreting cells (ISC) by peripheral blood mononuclear cells (PB-MNC) and purified B cells following stimulation with Staphylococcus aureus Cowan 1 (SAC) or with B cell stimulatory factor 2 (interleukin 6: IL-6), using the reverse hemolytic plaque assay in an attempt to clarify the immunological functions of peripheral blood B cells in patients with autoimmune thyroid disease (AITD). ISC response by PB-MNC following stimulation with SAC was significantly decreased in patients in the hyperthyroid state of Graves' disease and Hashimoto's thyroiditis as compared with that of normal controls. The difference in SAC-response was not significant between patients with euthyroid state of Graves' disease and normal controls. ISC response by PB-MNC following stimulation with SAC exhibited a reciprocal relationship to TRAb in patients with Graves' disease. Using purified B cells, some spontaneous ISC response without SAC stimulation was observed in patients in the hyperthyroid state of Graves' disease and Hashimoto's thyroiditis. This spontaneous ISC response was further enhanced by IL-6. These results suggest that in organ-specific autoimmune diseases such as AITD, immunological abnormalities exist in B cells and some B cells are nonspecifically activated in the immunologically active state.

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We have investigated the specific immune response to Epstein-Barr virus (EBV) of peripheral blood mononuclear cells (PBMC) from patients with malignant lymphoma of the thyroid. Coculture of PBMC and EBV resulted in EBV cell transformation and regression which was assayed by an EBVinduced B cell focus-regression assay technique. The EBV had been isolated from mouthwash samples. The specific immune response to EBV by outgrowth inhibition in PBMC from untreated EBV-seropositive patients with malignant lymphoma was significantly decreased when compared to PBMC from EBVseropositive healthy subjects (p<0.05). This observation is at least consistent with the possibility that B-cell proliferation after continuous or recurrent EBV infection could be a causative factor or may potentiate malignant lymphoma of the thyroid.

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We describe a 17-yr-old girl with insulin resistant diabetes, acanthosis nigricans, hirsutism and short stature. At the age of 14 she was found to have glycosuria and diagnosed as diabetes mellitus. No endocrinological abnormality except transient amenorrhea and exaggerated LH response to LHRH was found. Insulin resistance was demonstrated by fasting hyperinsulinemia, insulin tolerance test and euglycemic glucose, clamp test, and large doses of insulin with CSII were not effective in controlling blood glucose. Insulin binding to erythrocytes was normal, suggesting a postbinding defect. The same phenotype of insulin resistant diabetes and short stature was found in her mother who was diagnosed as diabetes mellitus at the age of 31 and died of diabetic nephropathy at the age of 41. Her maternal grandfather and uncle were reportedly affected with the same phenotype. Her father had impaired glucose tolerance, but no hyperinsulinemia. Two sisters had essentially normal glucose tolerance. Insulin binding to erythrocytes of her father and mother was also in the normal range. These results suggest that the present case may be a rare syndrome present together with type C syndrome of insulin resistance, and with short stature which was inherited autosomal dominantly.

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In this series, eighteen patients with Graves' disease were treated with 8000 rads (80Gy) of radioiodine (¹³¹I), using the new high resolutional ultrasonic scanner for the determination of the accurate weight of the thyroid gland. The mean dose of radioiodine administered orally was 4.6± 3.0mCi (170.2±110.0 MBq) and 133.7± 44.6 μCi/g (4.95 ± 1.65 MBq). At one year after treatment, twelve of eighteen patients (66.7%) became euthyroid, five (27.8%) remained hyperthyroid and one (5.6%) became hypothyroid. Analysis of various factors which may be related to the effect of radioiodine therapy revealed that the weight of the thyroid gland in the hyperthyroid and euthyroid groups was significantly different (61.7±33.5g vs. 25.1±9.1 g, p<0.05). Furthermore, all patients with larger glands (more than sixty grams) remained hyperthyroid, while the incidence of euthyroidism was as high as 80% in patients with smaller glands (less than forty grams). Although the number of patients studied was small, these results indicate that a larger thyroid gland requires a larger radioiodine dose per gram of tissue than a smaller gland, suggesting that the therapeutic radiation dose should be graded according to the gland size even when the gland size is accurately estimated by ultrasound. Further study is required to determine the appropriate radiation dose graded according to the gland size.

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We studied the response of plasma 7B2 to LHRH and ovine corticotropin releasing hormone (o-CRH) in healthy young subjects. The plasma 7B2 concentration significantly increased from 78.3±7.5 (mean±SEM) to 102.0±6.0 ng/L (142.7±12.7% of the basal value; P<0.01) following iv administration of LHRH in seven young subjects. On the other hand, no increase in plasma 7B2 was found after iv administration of o-CRH in six young subjects. These results, together with our previous report of no increase in plasma 7B2 after administration of TRH and GHRH in young subjects, suggest that pituitary 7B2 may be present in gonadotrophs and be released only by LHRH in physiological conditions.

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Factors associated with the basal level of serum thyrotropin (TSH) were analyzed over a wide range of pathophysiological conditions by means of a large laboratory database on thyroid function. When data were analyzed two-dimensionally, serum TSH showed significant inverse correlations with total triiodothyronine (T₃), free T₃ index (FT₃I), total thyroxin (TT₄) and free T₄ index (FT₄I) in the order of increasing intensity. The three-dimensional analysis, however, revealed that 1) total hormone levels were actually unrelated to serum TSH when the levels of free hormone indices were held constant, 2) the relation between FT₃I and TSH became obscure when the influence of FT4I was similary removed. On the other hand, 3) the relation of FT₄I with TSH was unaffected by the level of FT₃I.
These results suggest that free T₄ is the main determinant of the serum TSH level. This study also implies that it is possible to use large amounts of laboratory data to elucidate the overall profile of a given patho-physiological system, whose structure is only partially revealed by conventional clinical or animal studies.

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Antibodies to Yersinia enterocolitica serotype 03, 05, 06 and 09 were measured by the micro-agglutination method in 445 healthy subjects and patients with Grave's disease (n=70), Hashimoto's disease (n=45) and thyroid tumor (n=29). In contrast to previous reports, the incidence of antibodies to serotype 03 in each group of patients with thyroid diseases was not significantly different from that in healthy subjects. However, the incidence of antibodies to serotype 05 was significantly higher in patients with Graves' disease (81.4%, P<0.001) and Hashimoto's disease (91.1%, P<0.001) than in healthy subjects (58.9%). Significantly increased incidence of antibodies to serotypes 06 and 09 was observed only in patients with Hashimoto's disease (40.0% and 51.1% vs healthy subjects 24.7% and 29.9%, respectively). Patients with thyroid tumor showed no increase in any serotype of Yersinia enterocolitica. No correlations was found between the titers of anti- Yersinia antibodies and antithyroglobulin or anti-microsomal antibodies. These data indicate an association between thyroid autoimmunity and antibodies to Yersinia enterocolitica. These results are different from those in reports from other countries, seggesting that serotype specificity may be influenced by racial or genetic factors.

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The site of action of synthetic progestins or danazol in the treatment of endometriosis is considered to be mainly the hypothalamo-pituitary level, but the direct action to the uterine endometrium and the ovary is also suggested. We investigated the effect of these synthetic steroids to rat ovarian steroidogenic enzymes. The effect of norethisterone, levonorgestrel, danazol, gestrinone, desogestrel and 3-keto-desogestrel was studied in vitro. The sources of the enzymes were prepared from ovaries of immature rats treated either with pregnant mare serum gonadotropin (PMS) and human chorionic gonadotropin (hCG) for 3β-hydroxy steroid dehydrogenase (3β-HSD), or with PMS for 17α-hydroxylase and 17, 20 lyase. The substrates used were pregnenolone (P5) for 3β-HSD, progesterone (P4) for 17α-hydroxylase, and 17α-hydroxy-progesterone (17α-OH-P4) for 17, 20 lyase. The substrates were incubated with the enzyme sources and coenzymes, and the products formed were measured. All the steroids inhibited 3β-HSD, and the inhibition by gestrinone (Ki= 3.0μEM) and 3-keto-desogestrel (17.5μEM) was particularly marked. Only desogestrel (Ki= 30.3μEM) and danazol (168μEM) inhibited 17α-hydroxylase. All the steroids inhibited 17, 20 lyase, and the inhibition by desogestrel (Ki= 0.70μEM), danazol (0.80μEM), and gestrinone (30μEM) was particularly marked.

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We have shown that administration of estrogen which increases prolactin (PRL) synthesis in the rat may be mediated by an increase in poly [adenosine diphosphate ribose (ADP-ribose)] synthesis. Present investigation was attempted to study whether poly (ADP-ribose) synthesis is involved in rat PRL gene expression during early pregnancy. Anterior pituitaries were obtained on days 0, 2, 4, 6, 8, 10 and 12 of pregnancy (group C). Another group of pregnant rats was given nicotinamide, an inhibitor of poly (ADP-ribose) synthesis twice a day intra-peritoneally from day 0 to the day of sacrifice (group N). Serum estradiol (E₂) concentration was determined by radioimmunoassay. PRL mRNA was measured by cytoplasmic dot hybridization using ³²P-labeled cDNA. Poly (ADP-ribose) synthesis was assessed by incubating purified nuclei with ¹⁴C-nicotinamide adenine dinucleotide.
The serum concentration of E2 increased between days 2 and 4, and on day 6 it decreased to the level of day O. It remained low until day 12. No difference in the serum E2 level was observed in groups C and N. In group C, PRL mRNA increased from day 2 and remained high until day 8.
In group C, poly (ADP-ribose) synthesis increased between days 2 and 4, decreased on day 6 to the level of day 0, and thereafter gradually increased until day 10. Administration of nicotinamide abolished the increase in poly (ADP-ribose) synthesis observed in group C during early pregnancy. In group N, the increase in PRL mRNA was completely suppressed.
It is suggested that the increase in PRL mRNA in early pregnancy may be mediated by increased poly (ADP-ribose) synthesis. The increase in PRL mRNA and poly (ADP-ribose) synthesis early pregnancy are felt to be caused by an increase in E₂.

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The effect of exercise training on brown adipose tissue (BAT) thermogenesis was studied by measuring cytochrome oxidase activity, as a marker of mitochondrial abundance, mitochondrial guanosine-5'-diphosphate (GDP) binding, as an indicator of thermogenic activity and oxygen consumption in BAT in ovariectomized (OVX) obese rats and sham-operated rats. Six-week exercise training significantly suppressed body weight gain in OVX rats to the level of sendentary control rats, although food intake in exercise trained OVX rats increased more than in the sedentary OVX rats. Exercise training increased cytochrome oxidase activity, mitochondrial GDP binding and oxygen consumption in BAT in OVX rats, which were reduced in a sedentary condition, as well as in the control rats. These results suggest that exercise training potentiates BAT thermogenesis, which may contribute to the reduction of body weight in OVX obese rats.

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Calcitonin gene-related peptide (CGRP)-like immunoreactivity (LI) in the human hypothalamus was investigated by radioimmunoassay and by immunocytochemistry. CGRP-LI was detected from two hypothalami obtained at autopsy (2.1 and 7.0ng/g wet tissue) by radioimmunossay. Reverse phase high performance liquid chromatography revealed that most of the CGRP-LI in the human hypothalamus was eluted in an identical position with synthetic human CGRP. For immunocytochemistry, human hypothalami obtained at autopsy were fixed and cryostat-sectioned at 40μm. Free floating sections were immunostained with antibody to CGRP. CGRP-immunoreactive cell bodies were found in the supraoptic nucleus, paraventricular nucleus and infundibular nucleus. These findings indicate that CGRP exists in the cell bodies of the supraoptic nucleus, paraventricular nucleus and infundibular nucleus in the human hypothalamus and CGRP may play some roles in the endocrine and other functions of the human hypothalamus.

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Exercise-induced hyperketonemia was investigated using streptozotocin (STZ)-diabetic rats subjected to running exercise on a treadmill. The degrees of hyperketonemia after 50, 55 and 60% Vo_2max of exercises were similar in mild diabetic rats (fasting plasma glucose; FPG<11mM). The degree of hyperketonemia (especially an increase in acetoacetate; AcAc) after 60% VO_2max of exercise was correlated with FPG (P<0.01) and basal plasma ketone bodies (P<0.01). Prolonged training with 60% Vo_2max of exercise for 30 min 3 times per week for 6 wks reduced the increase in plasma ketone bodies induced by the exercise in both mild (FPG<11mM) and severe (FPG>22mM) diabetic rats. The exercise-induced increase in plasma glucagon in mild diabetic rats and free fatty acids (FFA) in severe diabetic rats are also reduced by the training. These results demonstrate that exercise-induced hyper-AcAc-emia correlated with the FPG level is reduced by prolonged training in diabetic rats, and might suggest that exercise-induced hyperketonemia is reduced by long-term exercise training also in diabetic patients.

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The therapeutic efficacy of the combination of cyproheptadine and bromocriptine was studied in 15 patients with active acromegaly showing incomplete GH suppression in response to bromocriptine therapy alone. The mean basal plasma GH was 31.3±5.5μg/L, and it decreased to 19.0±3.9μg/L during the single bromocriptine therapy (10 to 20mg for 2 to 21 months). When cyproheptadine (12 to 16mg for 8 to 52 months) was added to bromocriptine therapy, plasma GH decreased further (9.4±3.0μg/L: vs pretreatment, P<0.001; vs bromcriptine treatment, P<0.005), and GH normalization was obtained in 8 patients. The plasma somatomedin-C levels in these 8 patients (0.3-1.8U/ml) were within the normal range during the combination therapy. Plasma GH responses to TRH or GHRH were markedly suppressed in 6 patients during the combination therapy compared to pretreatment or during bromocriptine treatment. In addition, a clear reduction in the tumor size was observed in 4 of 7 previously untreated patients during the combination therapy. In conclusion, cyproheptadine has therapeutic efficacy in acromegalic patients who showed incomplete GH suppression in response to treatment with bromocriptine alone. Following the cyproheptadine and bromocriptine combination therapy tumor shrinkage was observed in some patients.

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Adenosine or vehicle; dibutyryl c-AMP, a c-AMP analogue, or vehicle in two separate experiments were infused through an indwelling cannula every four hours around the ovarian vascular pedicle of ewes unilaterally ovariectomized on day 8 postestrus. Adenosine or vehicle was infused from day 8 through 22 postestrus and dibutyryl-cAMP was infused from day 8 through 20 postestrus or until the ewes returned to estrus. Interestrous intervals were greater (p≤0.05) in ewes receiving adenosine (27.3±2.4 days) than in control ewes (17.2±1.3 days). The length of the estrous cycle of ewes receiving dibutyryl c-AMP was greater (22.4±1.1; p≤0.05) than in control ewes which averaged 16.7±0.6 days. Profiles of progesterone were different (p≤0.05) for ewes receiving adenosine or dibutyryl c-AMP when compared to their respective controls. In addition, the overall mean concentrations of progesterone were greater (p≤0.05) in dibutyryl c-AMP or adenosine-treated ewes than in controls. In a third experiment, infusions of adenosine or dibutyryl c-AMP intrauterine every 4 hours through a cannula from day 8 through 22 postestrus had no effect (p≤0.05) on the interestrous interval or profiles of progesterone. It is concluded that dibutyryl c-AMP or adenosine in vivo can delay luteolysis and adenosine and c-AMP may play roles in luteal secretion of progesterone in sheep but are probably not the uterine embryonic antiluteolysin of early pregnancy in sheep.

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Changes in 7B2 immunoreactivity in the pituitary as well as in the other brain regions and gut after various endocrine situations were investigated. Gonadectomy and neonatal monosodium glutamate (MSG) treatment resulted in an appreciable increase in the pituitary 7B2 concentration, though 7B2 content in the MSG treated pituitary was not significantly different when calculation was performed on a per pituitary gland basis. The 7B2 concentration in the cerebellum, midbrain and cortex in thyroxine treated rats showed a significant increase, which might indicate possible thyroid hormone involvement in 7B2 metabolism in the brain. The pituitary 7B2 concentration during the estrous cycle did not change significantly. These results suggest that pituitary 7B2 may correlate to the pituitary gonadotropins and that brain 7B2 content may be modulated by thyroid hormones.

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