Neuropeptide Y (NPY)-and somatostatin (SS)-like immunoreactivities (LI) were investigated in tumor tissues of one ganglioneuroma (GN), 3 ganglioneuroblastomas (GNB) and one neuroblastoma (NB) by radioimmunoassay. NPY-LI was detected from all 5 tumor tissues (16.4-1247 pmol/g wet tissue). Sephadex G-50 column chromatography and reverse phase high performance liquid chromatography (HPLC) revealed that most of the NPY-LI in tumor extracts was eluted in an identical position to synthetic human NPY except one GNB (case 2). In this case, most of the NPY-LI was eluted in a higher molecular weight region than synthetic human NPY in Sephadex G-50 column chromatography and in a more hydrophobic position in HPLC. SS-LI was detected from 4 tumor extracts except one GNB (case 2)(21.3-787 pmol/g wet tissue). Sephadex G-25 column chromatography and reverse phase HPLC revealed that SS-LI in tumor extracts was eluted just after the void volume and then in the same positions as SS-28 and SS-14. These results suggest that NPY, SS-14 and SS-28 exist in tumor tissues of GN, GNB and NB, and most of the NPY-LI in one GNB was a higher molecular and more hydrophobic form of NPY-LI.

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Peroxidase activities of autonomously functioning thyroid tumors (T) and surrounding non-tumorous tissue (N) in 5 patients were determined by employing guaiacol or iodide as the second substrates. The mean values for specific activities of T were 30 times (in iodide oxidation assay) or 4 times (in guaiacol oxidation assay) as high as those in N, being significantly higher than those of non-functioning tumors. The thyroglobulin-iodination activity of thyroid peroxidase in T was also found to correlate well to the iodide oxidation activity. These results suggest that the enhanced peroxidase activity in the nodules plays an essential role in the function of autonomously functioning thyroid nodules.

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A competitive, double antibody enzyme immunoassay for oxytocin in a heterologous system was developed. Horseradish peroxidase was conjugated with oxytocin using N-succinimidyl 3-(2-pyridyldithio) propionate, and rabbit anti-oxytocin serum was produced by immunization of oxytocin-bovine serum albumin complex which was prepared by the carbodiimide method.
The sensitivity of the assay was 4 μIU/tube, which corresponded to 10μIU per ml using 400μl of the sample which was extracted from the same volume of plasma by means of SEP-PAK C₁₈ cartridges.
The coefficients of variation for different levels of oxytocin ranged from 6.8-15.9% and 8.5-16.7%, for intra- and inter-assay. Recovery of oxytocin added to plasma after extraction was 99-117%.
No or little cross-reaction with arginine-and lysine-vasopressin was found.
Plasma oxytocin concentrations determined by the proposed enzyme immunoassay were well correlated with those determined by radioimmunoassay (r=0.90).

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The aim of this study was to determine whether atrial natriuretic peptide (ANP) alters β-endorphin (β-END) secretion from rat intermediate pituitary and whether this effect is a direct action on the intermediate pituitary or an indirect one mediated by hypothalamic factor (s). We studied the release of β-END from rat neuro-intermediate lobes of the pituitary (NIL) and from the hypothalamo-neurohypophysial complex (HNC), which consists of the hypothalamus, pituitary stalk, intermediate and posterior lobes of the pituitary, by means of an in vitro perifusion system. NIL and HNC were prepared from male Wistar rats and individually perifused for 30 min with perifusion medium followed by 20 min perifusion with medium containing a-rat ANP and/or dopamine (DA). Samples of perifusion medium were collected every 5 min and subjected to RIA for β-END. The basal release of β-END from NIL was 180% of that from HNC (p<0.01), which provides further support for the presence of hypothalamic factors that inhibit β-END release from the intermediate pituitary. The perifusion of HNC with ANP at 10^-7 and 10^-6M increased the β-END concentration by 25 and 50%, respectively (p<0.01). In contrast, ANP (10^-8 to 10^-6M) had no effect on β-END release from NIL. The inhibitory eect of DA (10^-6M) on β-END release from NIL and HNC (51% and 50% of the basal release, respectively, p<0.01) was confirmed. However, this inhibitory effect was not reversed by ANP: Therefore, it seems unlikely that the stimulatory effect of ANP on β-END release results from antagonizing DA action on the intermediate pituitary.
Since ANP had no direct effect on β-END release from NIL, the stimulatory effect of ANP on the release of β-END is thought to be an indirect one, mediated by hypothalamic factor (s).

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A 51-yr-old male patient with Cushing's syndrome due to huge nodular adrenocortical hyperplasia is described. Urinary 17-OHCS was not suppressed by a high dose of (8mg) dexamethasone and showed rather a tendency to paradoxical response. There was no response to metyrapone. Plasma cortisol showed a hyperresponse to insulin-induced hypoglycemia and a rapid response to corticotropin releasing hormone-lysine vasopressin (CRH-LVP) administration without an obvious ACTH response. Plasma cortisol responded to synthetic ACTH. Urinary 17-OHCS did not show parallel changes with plasma cortisol. These results and computerized tomography data suggested huge multiple nodular adrenocortical hyperplasia, which was confirmed later by surgery. The left and right adrenal glands weighed 105 and 45g, respectively. Hyperreaction of the adrenal gland to a small change in plasma ACTH or “unknown factors” may cause not only the discrepancy between cortisol and ACTH response but also the development of autonomous nodules in the adrenal gland.

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Thyroxine (T₄)-binding to serum proteins in primates; catarrhini, prosimiae, and platyrrhini were studied by polyacrylamide gel electrophoresis T₄ binding analysis. From the electrophoretic analysis, it was shown that thyroxinebinding proteins similar to human thyroxine-binding globulin (TBG) and thyroxine-binding prealbumin (TBPA) were present in catarrhini and prosimiae species, but not in platyrrhini (callithricidae and cebidae). T₄-binding analysis also revealed that catarrhini and prosimiae have a high affinity T₄-binding protein similar to human TBG. The association constant (Ka) for T₄ of the plasma proteins in these species was approximately 2.0×10¹⁰M^-1. On the other hand, it was unable to demonstrate a high affinity binding site for T₄ in the plasma of platyrrhini species. Both the total and free thyroid hormone concentrations in catarrhini and prosimiae were similar to those in human. Total T₄ in cebidae, one of the platyrrhini species, was extremely low. Among 8 animals examined, T₄ in 6 was undetectable by radioimmunoassay and the mean T₄ of the other two was 2.8μg/dl. However, free thyroid hormone concentrations were similar to those in human. In callithricidae, another platyrrhini species, T₄ in plasma was 6.90±2.11, which is comparable to the level in normal human subjects. However, in this species, high-affinity T₄-binding protein was lacking and free thyroid hormone concentrations were extremely high (most were higher than the assay limit). Although the thyroid function of callithricidae remains to be studied, it will be interesting if callithricidae is resistant to thyroid hormone action.

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The age at vaginal opening, estrous cyclicity, serum levels of luteinizing hormone (LH), follicle stimulating hormone (FSH) and prolactin (PRL) on the day of proestrus, and number of ova and ovarian weight as measured on the day of estrus in spontaneously hypertensive (SH) and genetically matched normotensive Wistar Kyoto (WKY) female rats were compared. In SH rats, there was a significant delay in the vaginal opening, but the regular 4-day estrous cycle followed afterwards. No significant changes were observed in the afternoon increase in serum LH, FSH and PRL on the day of proestrus in SH and WKY rats, although the basal levels of LH and PRL in the morning (11: 00h) were lower in SH rats than in WKY rats. The mean number of ova in SH rats was also less than in WKY rats, whereas the ovarian relative weight was similar in both species of rats. It can be said that SH rats undergo certain, but not critical, endocrine and/or neuroendocrine changes related to reproduction.

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A 56-year-old man with primary aldosteronism and chronic renal failure undergoing hemodialysis is described. He complained of numbness of the extremities and showed persistent hypopotassemia in spite of anuria. In the endocrinological examination, a very high plasma aldosterone concentration was observed, while plasma renin activity was within the normal range. From the abdominal Computed Tomography (CT), adrenal scintigraphy, and segmental venous sampling data, he was diagnosed as primary aldosteronism due to left adrenocortical adenoma.
In this case, hypopotassemia could not be explained by potassium loss through the kidneys, which suggests potassium excretion in the gastrointestinal tract as the mechanism of hypopotassemia. This was clearly shown from a potassium-balance study and the results of spironolactone administration. Our report is on the first case showing hypopotassemia due to primary aldosteronism in spite of anuria. If a patient treated with maintenance dialysis should have persistent hypopotassemia, as in the present report, it is necessary to consider an association with primary aldosteronism.

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To determine whether beta-blockade protects rat heart against thyroxine (T₄)-induced accelelation of lipid peroxidation, in vivo effects of 3 beta-blockers with different ancillary properties on the mitochondrial oxidative enzyme, antioxidant enzymes and lipid peroxide were investigated. The rats were rendered hyperthyroid by adding T₄ to their drinking water for 3 weeks and were treated simultaneously with either carteolol (a blocker with partial agonist activity; 30mg/kg/day), atenolol (50mg/kg/day) or arotinolol (a blocker with weak alpa-blocking action; 50mg/kg/day). The T₄-induced tachycardia was alleviated completely by either atenolol or arotinolol, but only partially by carteolol. Cytochrome c oxidase activity in the heart muscle was increased by T₄ with a parallel increase in manganese (mitochondrial) superoxide dismutase. Atenolol, but neither carteolol nor arotinolol, suppressed this increase. Similarly, the T₄-induced acceleration of lipid peroxidation was suppressed by atenolol alone. Glutathione peroxidase was markedly decreased, and both copper zinc (cytosolic) superoxide dismutase and catalase were also decreased or tended to be decreased by T₄. The levels of these 3 enzymes were only minimally affected by the beta-blocker treatments. These results suggest that beta-blockade suppresses mitochondrial hypermetabolism and protects heart muscle against oxidative stress in hyperthyroidism, and that the ancillary properties of beta-blockers such as partial agonist activity and alpha-blocking action negate the protection.

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Eight hypogonadotropic growth hormone-deficient children were treated with human chorionic gonadotropin (HCG) while they continued to receive a fixed dose of HGH for a one year period. They were observed for changes in somatomedin C (IGF-I) and height increase velocity. Mean somatomedin C was 0.79±0.30 U/ml in normal prepubertal children (N=7) and 0.78±0.31 U/ml in prepubertal normal short children (N=22). At pubertal stage 3, somatomedin C was 2.21±1.23 and 2.05±0.44 U/ml in normals (N=5) and in normal short children (N=7), respectively.
When 3000-5000 units/week of HCG were given to each of the 8 hypogonadotropic growth hormone-deficient children who were receiving HGH at a mean dose of 0.33±0.05 IU/kg/week, testosterone increased from less than 0.3 ng/ml to more than 5ng/ml at 6 months in 3 cases and at 12 months in 2 cases, while the testosterone concentration was less than 3.5 ng/ml in the remaining 3 cases. The rate of height increase rose significantly (p<0.001) from 5.2±1.0 to 9.3±1.4 cm/year mimicking the normal pubertal growth spurt. However, the mean somatomedin C concentration was 0.44±0.23 before therapy, 0.33±0.30 at 6 months and 0.31±0.14 U/ml at 12 months after the start of HCG therapy.
It is concluded that the pubertal growth spurt induced by HCG in hypogonodotropic GH-deficient male children is not mediated by the increase in somatomedin C production.

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Hypothalamic-pituitary function was evaluated in a combination of tests with four hypothalamic releasing hormones (4RHs) and L-dopa in normal subjects and in patients with hypothalamic and/or pituitary disorders. Plasma concentrations of anterior pituitary hormones (GH, ACTH, TSH, PRL, LH and FSH) were measured before and after simultaneous iv administration of GHRH, CRH, TRH and LHRH. In addition, changes in the plasma levels of GHRH and GH were investigated before and after oral administration of L-dopa. Normal subjects showed appreciable responses to both tests. In five patients with hypothalamic disorders, the response of plasma anterior pituitary hormones varied, but plasma GHRH and GH did not respond to L-dopa. Patients with idiopathic and postpartum hypopituitarism showed low response to 4RHs or none at all, but L-dopa evoked a normal GHRH response in 2 of the 4 cases having no GH response. In the patients with hypopituitarism due to resection of a pituitary tumor, the response of anterior pituitary hormones to 4RHs was low, and L-dopa administration induced a normal GHRH and low GH response in 5 out of the 7 cases. After 4RHs administration, the patients with ACTH deficiency syndrome showed different patterns of impaired ACTH secretion, and isolated, combined or limited ACTH reserve. Seven patients with anorexia nervosa showed exaggerated GH, delayed TSH and FSH, low ACTH and LH, that is, normal PRL response to 4RHs, but no response of plasma GHRH or GH to L-dopa, suggesting the presence of hypothalamic dysfunction. These results indicate that the combination of the 4RHs test and L-dopa test is a simple and useful means for evaluating hypothalamic-pituitary function by measuring the response of plasma GHRH and six anterior pituitary hormones in the patients with endocrine disorders.

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The binding assay of prolactin (PRL) to the receptor in the rabbit mammary gland was carried out with varying concentrations of NaCl, KCl, CaCl₂, MgCl₂, glycerol, glucose, sucrose and urea. The agents did not affect the binding capacity. The ionic bond-breaking agents (NaCl and KCl) had little effect on changes in the association rate constant (k₊₁) of PRL binding to the receptor and the dissociation rate constant (k_{_1}) of bound PRL. The inclusion of other agents changed the k₊₁ and the k_-1. Among the agents examined, chaotropic salts (CaCl₂ and MgCl₂) inhibited the binding of PRL greatly, and were the most effective in decreasing the k₊₁. Both hydrogen- and hydrophobic bonds are involved in the interaction between PRL and the receptor. The data suggest that hydrophobic bonding is primarily an important force participating in the binding of PRL to its receptor.

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The influence of NaCl, KCl, CaCl₂, and MgCl₂ on the binding of prolactin (PRL) to its receptor was investigated. The salts were dissolved in a metallic ion-free binding buffer and had biphasic effects on changes in the association rate constant (k₊₁) of PRL binding, depending on their concentrations: there was an increase in the k₊₁ at lower concentrations and a decrease at higher concentrations. The dissociation rate of bound PRL was unaffected. NaCl at any concentration did not change the binding capacity. Bivalent salts, at higher than 25mM, increased the capacity about 1.6-fold as compared to the 0mM control. By cross-linking the PRL-receptor complex, the band of a molecular weight (Mr) 34, 500 receptor could always be detected on the autoradiogram. An Mr 78, 000 receptor appeared only after incubation with bivalent salts. Data indicate that the binding of PRL to an Mr 78, 000 receptor is directly regulated by bivalent cation.

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Porcine pancreastatin (1.19 nmol) was administered into the peripheral vein (i.v.) or the third cerebral ventricle (i.t.v.) of dogs and its effect on the secretion of insulin and pancreatic polypeptide (PP) studied. Neither means of administration had any effect on basal and glucose-induced insulin or PP secretion. However, i.v. pancreastatin did inhibit the i.v. CCK-8-induced insulin but not PP release. Pancreastatin may thus play a role in the regulation of insulin secretion in the canine pancreas.

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To investigate the mechanisms of the synthesis and the release of gonadotropin, rat anterior pituitary cells were stimulated in vitro with luteinizing hormone releasing hormone (LH-RH), [D-Ser (tBu)] ⁶ des-Gly-NH₂¹⁰ ethylamide (Buserelin) and 12-0-tetradecanoyl phorbol-13-acetate (TPA), and then the LH and LH-β subunit released into the medium were determined by radioimmunoassay. Buserelin showed its biological activity at a much lower concentration than LH-RH, but both of them caused the release of LH and LH-P subunit in a dose-dependent manner. Furthermore, intracellular LH synthesis fromLH-β subunit by stimulation with LH-RH or Buserelin was also found. After inducing various degrees of desensitization by stimulation with LH-RH or Buserelin in a dose-dependent manner (the first stimulation), pituitary cells were stimulated with a fixed dose of TPA (the second stimulation) and the released LH was assayed. LH was released almost constantly by the second stimulation, regardless of the dose used for the first stimulation. These results suggest that the C-kinase pathway was unaffected by the desensitization induced with LH-RH or Buserelin.

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The albumin index (mg/g·creatinine) was determined in untimed spot urine collected in the early morning from 92 randomly selected outpatients with noninsulin-dependent diabetes mellitus (NIDDM). The patients were divided into three groups: 49 patients with normo-albuminuria (albumin index less than 9.1), 24 with micro-albuminuria (albumin index between 9.1 and 100), and 19 with overt-albuminuria (albumin index over than 100). With diabetic duration, the frequency of the patients with overt-albuminuria was increased, but that with normo-albuminuria was decreased. The patients treated with only a diet almost showed normo-albuminuria. In contrast, microand overt-albuminuria were found more frequently in the patients treated with oral hypoglycemic agents or insulin. Micro- and overt-albuminuria were found more frequently in the patients with poor glycemic control than in those with good glycemic control. The urinary albumin index was significantly high in the micro-albuminuric patients with poor glycemic control. Similarly, micro- and overt-albuminuria were found more frequently in the patients associated with diabetic retinopathy or neuropathy than in those without diabetic complications. In addition, overt-albuminuria was found more frequently in the patients with hypertension. The urinary albumin index was significantly high in the overt-albuminuric patients with hypertension. In conclusion, the determination of the albumin index in spot urine may be convenient and clinically useful for the evaluation of diabetic nephropathy in outpatients with NIDDM.

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Nucleic acids were extracted from the tumor (1T-1) and punned to give poly (A)-containing RNA, which was subjected to protein synthesis in vitro with a wheat germ extract. Gel-filtration (Bio Gel P-30) profiles of the translated product showed the presence of glucagon-like substance, and the results of treatment of fractions with glucagon antibodies (30K or K4023) showed the possibility that translated products contained true-glucagon. This confirms glucagon synthesis in IT-1. The molecular weight of the translated glucagon was estimated to be 3, 000 from the K-value. The time courses of the glucagon synthesis were examined in cultured tumor cells (ITC-1) using ³H-leucine as a tracer. A large molecular weight protein was already detected after pulse labeling for 1 h. The amount of labeled glucagon in the cells was shown to be maximum at 1 h. True-glucagon was converted at 3 h to smaller molecular weight peptides which reacted with the C-terminal antibody of glucagon. In vitro protein synthesis, peptides with molecular weights of around 10, 000 were major products in 15-30 min.

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To investigate glucagon (IRG) and insulin (IRI) responses to alanine infusion in obesity and to assess the effect of body weight reduction with respect to hormonal balance, we compared six obese subjects with nine normal weight controls. None of the subjects were diabetic by OGTT criteria. Plasma IRI and IRG were measured following IV alanine at a rate of 0.1 g/kg over a period of 2 min. Our obese subjects had an increase in IRG response to alanine, which was due to decreased suppression of alpha-cell function due to insulin resistance. Weight reduction via calorie restriction reduced insulin demand, resulting in reduced plasma IRI by restoring beta-cell function, and the IRG response was paradoxically decreased as compared with that before weight loss. It is conceivable that improvements in insulin sensitivity after body weight reduction may re-establish the normalization of pancreatic betacell function and the insulin-induced inhibition of IRG secretion. Our obese subjects were characterized by decreased IRG secretion which was reflected in a change in body weight reduction.

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The aim of this study is to investigate the possibility of determining the appropriate amount of thyroid tissue to leave behind as remnant weight in subtotal thyroidectomy for Graves' disease by measuring the TBII value, and correlating the outcome to the grade of intrathyroidal lymphocyte infiltration.
We therefore have investigated the levels of TBII in the thyroidal (T-TBII) and peripheral (P-TBII) venous blood, and the grade of lymphocytic infiltration and lymph follicle formation in the intrathyroidal tissue. There was no parallel relationship between the T-TBII value and the grade of lymphocytic infiltration and lymph follicle formation. There was no marked difference between the T-TBII value and the P-TBII value. It was thus not possible to use these data to determine the proper remnant weight of Graves' thyroid tissue at the time of surgery.

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An acquired partial pituitary insufficiency with selective ACTH and GH deficiency was demonstrated in two men aged 47 and 54, for which the clinical course over many years corresponds to Addison's disease. In one of the 2 cases, antibodies to anterior pituitary cell membrane, assayed by an immunofluorescence method with GH₃ cells (rat GH and prolactin secreting cell) and AtT-20 cells (mouse ACTH secreting cell) as antigens, were positive. We also present a 55-year-old man with isolated ACTH deficiency associated with transient GH deficiency. In this case, hydrocortisone replacement corrected his subnormal, pre-therapy GH response to insulin tolerance and glucagon propranolol tests, although there was no response of serum GH to L-dopa and arginine stimulation test before therapy. Selective ACTH and GH deficiency are very rare and the finding of transient GH insufficiency in a patient with isolated ACTH deficiency suggests that repeated testing while on hydrocortisone replacement therapy is of great diagnostic importance in order to distinguish between selective ACTH and GH deficiency and isolated ACTH deficiency accompanied by transient GH insufficiency.

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