A 43-year-old woman with isolated ACTH deficiency in association with transient thyrotoxicosis is reported. The initial evaluation revealed that plasma ACTH and cortisol did not respond to corticotropin-releasing hormone (CRH) in the presence of hyperthyroxinemia and hyperprolactinemia. During the replacement therapy with dexamethasone, she developed transient hypothyroxinemia with persistent hyperprolactinemia. Although thyroid open biopsy did not show any evidence of autoimmune thyroiditis or subacute thyroiditis, the data appear to provide other evidence of a possible relationship between acute adrenal insufficiency and transient thyroid dysfunction.

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We report a patient with pseudohypoparathyroidism (PHP) in whom parathyroid hormone (PTH) infusion failed to produce an increase in urinary adenosine 3', 5' monophosphate (cAMP) excretion in spite of the positive urinary phosphate excretion. The dbcAMP infusion test showed almost the same increase in phosphate as in the E-H test, although high urinary cAMP excretion was detected. Furthermore, a PTH infusion test in combination with calcium antagonist (diltiazem) administration markedly increased phosphate excretion, whereas the response of urinary cAMP excretion also remained negative. After treatment with 1α(OH) D₃, phosphaturic response increased by at least 14.3 mg/2 h compared with that in the pretreatment period. Therefore, intra and extra cellular calcium seem to affect the phosphaturic response induced by PTH.

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This study has investigated the effect of a long period of overeating on the glycemic control and pancreatic β-cell function in neonatally streptozocin treated impaired glucose tolerant mice. Neonatally streptozocin (60mg/kg) treated male ICR mice with 150-200mg/dl of fed blood glucose levels were divided into two groups at 6 weeks of age. One group was maintained on a cafeteria diet (SZC) and the other on ordinary mouse chow (SZ) until 30 weeks of age. Normal male ICR mice were divided into a cafeteria diet group (CC) and an ordinary chow group (Cont). SZC and CC consumed 134-124% of the caloric intake in SZ and Cont throughout the study. Marked elevation of the fed blood glucose level was observed and the glucose tolerance was progressively impaired in SZC. On pancreas perfusion at 30 weeks of age, insulin secretion to 30m M glucose in SZC was significantly decreased compared with that in SZ. That in CC was slightly decreased compared with that in Cont. The pancreatic insulin concentration in SZC was significantly less than that in SZ. We conclude that chronic hyperglycemia, induced by the long period of overeating, accelerated the selective loss of β-cell sensitivity to glucose. Even in normal mice that did not have marked hyperglycemia, insulin secretion to glucose was suppressed, probably by chronic stimulation of the β-cell due to the long period of dietary excess.

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We have established 13 hybridoma cell lines which secrete mouse IgGi monoclonal antibodies (McAbs) to human growth hormone (hGH). Binding affinity and binding specificity of McAbs were analyzed by competitive radioimmunoassay. Among these McAbs, CL. Bl showed a high affinity of 9.8×10⁸l/mol, and all McAbs so far tested showed very weak cross-reactivity or none at all with human prolactin (hPRL) and human chorionic somatomammotropin (hCS; human placental lactogen). Analysis of binding sites of McAbs using hGH variant and fragments in both ELISA and RIA demonstrated that McAbs could be classified into two groups. All the McAbs obtained in this study bound to plasmin-digested fragment S2 (hGH 1-134 and 141-191) and fragment α3 (hGH 1-134 and 147-191). However, five (such as 1D2) out of 13 McAbs bound to fragment F 1 (hGH 1-134) and others (such as CL. B1) did not. The McAb CL. B1 in the latter group showed low affinity with 20 K hGH (residue 32-46 deleted in native 22 K hGH) in contrast to high affinity with hGH (22K). This suggests that the former McAbs recognize an epitope located at the N-terminal two-third part of hGH. In contrast, the McAbs of the latter group are likely to recognize three-dimensional structure of native 22K hGH.

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The role of insulin in norepinephrine turnover (NE) and thermogenesis in brown adipose tissue (BAT) after acute cold-exposure was studied using streptozocin (STZ)-induced diabetic rats. NE turnover was estimated by the NE synthesis inhibition technique with α-methyl-p-tyrosine. BAT thermogenesis was estimated by measuring mitochondrial guanosine-5'-diphosphate (GDP), cytochrome oxidase activity and mitochondrial oxygen consumption in BAT at an ambient temperature of 22°C and during a six-hour cold-exposure at 4°C. In insulin-deficient diabetic rats, the NE turnover, mitochondrial GDP binding, cytochrome oxidase activity and mitochondrial oxygen consumption in BAT at 22°C were significantly reduced, compared with those of control rats. Treatment of STZ-induced diabetic rats with insulin prevented a decrease in NE turnover and BAT thermogenesis. Acute cold-exposure increased the NE turnover of BAT in insulin-deficient diabetic rats. The BAT thermogenic response to acute cold-exposure, however, did not occur in insulin-deficient diabetic rats. These results suggest that insulin is not essential in potentiating NE turnover in BAT after acute cold-exposure, but is required for cold-induced thermogenesis.

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The effects of 3-hydroxybutyrate (3-OHB) and hyperosmolarity on glucagon secretion were examined in the isolated perfused canine pancreas. When 3-OHB was infused for 15min into the pancreas perfused with 2.8mM glucose, 5 and 20mM sodium 3-OHB inhibited it after a transient stimuration, whereas a similar transient stimulation was observed also by the infusion of 20mM NaCl in a control experiment. The above inhibition was not observed under the perfusate condition of 5.5mM glucose plus 10mM arginine. When the isolated canine pancreas was perfused under the perfusate condition of acidosis (pH 7.1), ketoacidosis (pH 7.1 and 20mM 3-OHB) or hyperosmolarity (+60 mOsm/kg with sucrose) throughout the experiment, the glucagon concentrations produced by 2.8mM glucose under the ketoacidotic and hyperosmolar conditions, were less than half of those obtained under the standard condition. The insulin level was not influenced by the above perfusate conditions. These results suggest that 3-OHB inhibits glucagon secretion stimulated by glucopenia, but does not inhibit it stimulated by amino acids, and that hyperosmolarity inhibits glucagon secretion but does not inhibit insulin secretion. The pathophysiological significance of these results must be slight, considering the presence of hyperglucagonemia during prolonged starvation or diabetic ketoacidosis.

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The action of prolactin (PRL) on the secretion of gonadotropin was investigated by means of a cell culture system of rat anterior pituitary gland. Anterior pituitary glands were removed from Wistar male rats, enzymatically digested and cultured. Luteinizing hormone (LH) release into medium was increased by adding PRL dose-dependently in the range between 10ng/ml and 1μg/ml. This effect of PRL was further augmented by the presence of either gonadotropin-releasing hormone or estradiol. The intracellular LH concentration was also increased by PRL. PRL also caused an increase in folliclestimulating hormone release into medium dose-dependently.
In conclusion, PRL was shown to stimulate the secretion of gonadotropin at the pituitary level, thus suggesting a paracrine mode of PRL action in the anterior pituitary gland.

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We reviewed the pathophysiology of our previously reported female patient who had glucocorticoid-responsive hyperaldosteronism and was treated successfully with daily dose of dexamethasone (Dex) for 21 years. In this present study, the possibility that the patient may have 17α-hydroxylase deficiency (17-OH-D) mainly in the adrenal could not be ruled out. We therefore reviewed 31 Japanese patients diagnosed as having 17-OH-D with suppressed plasma renin activity reported in Japan. Among these patients, 9 were found to have a high plasma aldosterone (Ald) concentration (PAC)(group I). Twenty-one patients had either normal or low-normal PAC and the remaining patient had low urine Ald (group II). The slight cross-reactivity of the anti-Ald-antibodies used with 17-deoxy-steroids such as progesterone, 11-deoxycorticosterone and corticosterone which were increased in both groups did not explain the increased PAC in group I. In the patients in group I and group II with high-normal basal PAC, PAC further increased after ACTH and was suppressed by Dex. PAC in 2 group I patients, however, did not respond to angiotensin-II or angiotensin-III infusion. PAC in patients in group II with low or low-normal basal PAC responded equivocally to ACTH and Dex. The basal plasma cortisol in group I was lower than in group II, and plasma cortisol level after ACTH in group I appeared to remain at a lower level than that in group II patients. Among the study subjects, 28 showed a negative correlation between basal PAC and plasma cortisol. A possible discrepancy in the deficiency of 17ahydroxylase activity in adrenal and gonadal glands was also suggested in three 17-OH-D patients. The pathophysiology of Ald secretion and discrepancy in the deficiency of the enzyme activities in both glands in 17-OH-D patients was discussed.

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To clarify whether cigarette smoke stimulates the sympathetic nervous system (SNS) and thermogenesis in interscapular brown adipose tissue (IBAT), we measured norepinephrine (NE) turnover, an indicator of SNS activity, guanosine-5'-diphosphate (GDP) binding, a thermogenic indicator, and oxygen consumption in IBAT in monosodium-L-glutamate (MSG)-induced obese and saline control mice following a two-week exposure to cigarette smoke. Cigarette smoke significantly increased NE turnover, GDP binding and oxygen consumption in IBAT, and significantly reduced body weight in MSG obese mice as well as in control mice. However, food intake was unchanged in the MSG group.
These results suggest that cigarette smoke stimulates NE turnover and thermogenesis in BAT, which contribute to the mitigation of obesity.

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We reported a case with increased serum immunoreactive insulin (IRI) and Cpeptide immunoreactivity (CPR). The molar ratio of IRI to CPR was also increased. The propositus was diabetic with background retinopathy and neuropathy. No antibody to insulin or insulin receptor was detected in his serum and his insulin resistance was not so remarkable. When the serum was fractionated by gel filtration, about 90% of total IRI was recovered in the fraction where biosynthetic human proinsulin was eluted. The major part of the CPR was also recovered in the same fraction as proinsulin-like material. His daughter, 28 years old, a non-obese female, also had high IRI, CPR and a high molar ratio of IRI to CPR. A gel filtration study demonstrated the same elution profile as the propositus. Tryptic digestion failed to convert the proinsulinlike material from the propositus to insulin in a sufficient quantity to convert human proinsulin to insulin.
These data strongly suggest that this family is a new case of familial hyperproinsulinemia, and the defect resides in the proinsulin molecule, not in the converting enzymes.

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To investigate the relationship between plasma neuropeptide Y (NPY) concentrations and blood pressure in haemodialysis (HD), we measured plasma immunoreactive neuropeptide Y (IR-NPY) concentrations and blood pressure before and after HD in 71 patients undergoing maintenance HD. Plasma IR-NPY concentrations were measured by radioimmunoassay after extraction with Sep-Pak C18 cartridges. We corrected the plasma IR-NPY values after HD by reference to the ratio of the plasma total protein levels before HD to the levels after HD, in order to exclude the infulence of the haemoconcentration caused by HD.
Plasma IR-NPY concentrations before and after HD in 71 patients undergoing maintenance HD were 413±94pg/ml and 340±90pg/ml (mean±SD), respectively. Plasma IR-NPY concentrations before HD in 28 hypertensive patients with HD (398±91pg/ml) were not significantly different from those in 40 normotensive (427±98pg/ml) and 3 hypotensive (372±21 pg/ml) patients with HD (P>0.1). Plasma IR-NPY concentrations after HD in 9 patients whose systolic blood pressure fell more than 30mmHg during HD (409±52pg/ml) were significantly higher than those in the other patients (P<0.025).
These findings suggest that the release of NPY is increased when the blood pressure falls during HD in patients undergoing maintenance HD.

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The effect of mesenchyme on both proliferation and differentiation of mammary epithelial cells was investigated in a primary cell culture system. Mammary cells cultured on collagen gel for 4 days produced casein in response to the synergistic action of insulin, cortisol, and prolactin. When mammary epithelial cells were co-cultured with fibroblasts derived from three different kinds of fetal mesenchymal tissues, casein production was suppressed. The addition of conditioned media obtained from cultures of these mesenchymal cells stimualted DNA synthesis and reduced casein synthesis in a dose-dependent fashion in the cultured mammary cells. Although such biological actions are similar to those of epidermal growth factor (EGF), the capability to compete with EGF for EGF receptor was not found in this conditioned medium. Sephadex G-200 column chromatography revealed that molecular weight of the peak which has these biological activities was around 100, 000. These results indicate that fetal mesenchymal cells secrete a substance (s) which has a stimulatory effect on proliferation and an inhibitory effect on differentiation of mammary epithelial cells.

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A total of 94 patients with Turner's syndrome were treated with methioninefree recombinant hGH for one to two years. Forty-seven patients were treated with r-hGH at a weekly dosage of 0.5 IU/kg and another 47 were treated with 1.0 IU/kg/w by daily sc injection. Both treatment groups showed statistically significant growth increase during the treatment from 3.7±1.0 to 5.2±1.3 and from 3.5±0.9 to 6.3±1.4 (Mean±SD) cm/year, respectively, during the first year of treatment. During the 2nd year of treatment, the growth rate declined to 4.1±1.1cm/year under 0.5IU/kg/w treatment and to 4.6±1.1cm/year under 1.0IU/kg/w treatment. Nevertheless, the growth rates in the treatment groups remained significantly greater than in the untreated controls.
Plasma somatomedin C increased and no remarkable increase in bone age was observed during the treatment in either treatment group. Antibody to hGH was observed in 14.8% of the patients at the end of the first year of treatment, however the incidence was decreased to 4.7% by the end of the second year of treatment. Otherwise, there were no significant changes detected in physical or laboratory tests. No glucose intolerance necessitating treatment was observed.
These results indicate that hGH treatment is useful in accelerating growth in patients with Turner's syndrome.

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The binding of ¹²⁵I-epidermal growth factor (EGF) and activities of EGFreceptor autophosphorylation and of tyrosine-specific protein kinases were determined in hepatic membrane fraction from newborn, fetal and hepatectomized adult rats and compared with those of adult control rats. Although the EGF binding was decreased, there was a tendency for the activity of autophosphorylation to be higher and ligand-dependency to be lower in the membranes from growing hepatic tissues. The activity of tyrosine kinases did not differ among animal groups but a supplement of (NH₄) ₂SO₄ to the incubation mixture revealed a difference in the EGF-dependency of the activity; the salt inhibited the activity in the control more profoundly than in the newborn and fetus but the activity was partially restored in the presence of EGF, while in the newborn and fetus the activity did not respond to the added EGF. The results suggest that the higher activity with less responsiveness to the ligand of EGF-receptor autophosphorylation and protein-tyrosine kinase is one of the characteristics of growing rat hepatic tissues.

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The effect of neuromedin B (NMB) on insulin and glucagon release was studied in isolated perfused rat pancreases. Infusion of NMB (10nM, 100nM and 1μM) did not affect the insulin release under the perfusate conditions of 5.5mM glucose plus 10mM arginine and 11mM glucose plus 10mM arginine, although 10nM NMB tended to slightly suppress it under the perfusate condition of 5.5mM glucose alone. The degree of stimulation of insulin release provoked by the addition of 5.5mM glucose to the perfusate was not affected by the presence of 10nM NMB. The glucagon release was slightly stimulated by the infusion of 100nM and 1μM, NMB but not by 10nM NMB under the perfusate condition of 5.5mM glucose plus 10mM arginine. The effect of C-terminal decapeptide of gastrin releasing peptide (GRP-10) was also examined and similar results were obtained; 10nM and 100nM GRP-10 did not aifect insulin release and 100nM GRP-10 stimulated glucagon release under the perfusate condition of 5.5mM glucose plus 10mM arginine.
The present results concerning glucagon release are consistent with the previous results obtained with isolated perfused canine and porcine pancreas. However, the results regarding insulin release are not. Species differences in insulin release are also evident with other neuropeptides such as substance P and the mechanism of such differences remains fo be clarified.

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To elucidate catecholamine (CA) secretory dynamics in neuroblastoma, urinary excretion of CAs and their metabolites was serially measured in 6 patients aged 3 months to 3 years before and during treatment. After tumor extirpation, increased urinary CAs were promptly normalized; the reduction reflected the amount of CA production from the tumor. Urinary dopamine (DA) showed the most prominent reduction, whereas DA content in the tumor was very small, indicating that the DA produced was immediately released from the tumor and metabolized in extra-tumor tissues. In contrast, patients receiving chemotherapy continued to excrete excess DA and homovanillic acid (HVA), which were increased further at recidivation. One patient showed an inverse correlation between DA and norepinephrine (NE) excretion; a decrease in DA was associated with an increase in NE and plasma DA-β-hydroxylase (DBH) activity. A similar inverse correlation was also noted between NE and vanillylmandelic acid (VMA) or 3-methoxy-4-hydroxyphenylglycol (MHPG) excretion, while HVA and dihydroxyphenylacetic acid (DOPAC) were positively correlated with DA excretion. Urinary HVA and VMA were lineally correlated but in a patient excreting an enormous amount of DA, urinary VMA was markedly suppressed in terms of HVA excretion. Excessive DA induced an increase in renal water output but did not enhance Na and K excretion. These results indicate that endogenous DA overload in neuroblastoma inhibits NE production by suppressing DBH activity as well as by forming VMA and MHPG. This precursor regulation appears to be the characteristic of the CA metabolic pathway.

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In normal children aged one month to 16 years, the plasma active renin concentration (PARC) was measured with a renin immunoradiometricassay (IRMA) kit, and was compared with plasma renin activity (PRA). The IRMA for renin was found to be independent of the amount of renin substrate and not affected by the dilution of plasma samples, and was therefore proved to be a simple and reliable method. PRA measured in non-diluted plasma samples correlated well with PARC. In the age-related change, PARC in infants was significantly higher than that in older children. In infants, PARC was markedly higher in the crying state than that in the non-crying state. In normal children aged 7 to 11 years, PARC was significantly increased in the upright position compared to the supine position. These findings suggest that a hyperresponse of PARC to acute stress during blood sampling may cause an increase in active renin secretion in infants, and that stimulation by short-term standing may accelerate the activation of inactive renin or the release of active renin.

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The chronic administration of GnRH agonists to women results in the reversible suppression of estrogen production by the ovary. In the present the mechanism of the GnRH agonist suppression of estrogen production investigated in patients with endometriosis. During the treatment with intranasal buserelin spray, the concentration of serum estradiol-17β(E₂) was suppressed to near-castrate levels. Despite this marked suppression of serum immunoreactive LH and FSH levels in serum were not changed. On the hand, serum bioactive LH was markedly reduced. It was also observed the treatment that the pituitary LH pulse disappeared and pituitary response to exogenous GnRH was significantly suppressed. In contrast, ovarian response to human menopausal gonadotropin (hMG) was not altered the treatment. These findings suggest that the GnRH agonist suppression of estrogen production in the patients with endometriosis is through suppression of the secretion of biologically active LH and the reduction the LH pulse, but not through a direct inhibitory effect on ovarian estrogen biosynthesis.

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Male mice castrated on day 0 after birth were pretreated daily with testosterone propionate (TP, 4μg/g body weight), 17β-estradiol (E₂, 0.2μg/g body weight) or vehicle for 21 days starting from day 20. In another experiment, male mice were castrated on day 25; two pituitaries from 60-day-old females were immediately grafted under the capsule of the left kidney in one group. The castrated mice with or without grafts were pretreated daily with TP (4 or 20μg/g body weight) for 36 days starting from day 25, and the left kidney was removed on day 60. Daily TP injections (4μg/g body weight) were started again at 30 days after the end of pretreatments to examine androgen-induced proliferation, and incorporation of 5-[¹²⁵I] iodo-2'-deoxyuridine into the whole seminal vesicles was used as an index of proliferation. In the neonatally castrated mice, both TP and E₂ pretreatments given during the prepubertal period significantly increased seminal vesicle weight even long after the end of the pretreatments. However, androgen-induced proliferative response found in the neonatally castrated adult mice (poor response; long duration with a low peak) was changed to that found in mice castrated at adulthood (good response; short duration with a high peak) by the TP pretreatment only but not at all by the E₂ pretreatment. In the mice castrated on day 25, a pharmacological dose of TP or TP plus hyperprolactin could not enhance or change the adult castration type of androgen-induced proliferation induced by physiological prepubertal androgens, although both treatments significantly enhanced the prepubertal growth of the seminal vesicles.

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