Glucose metabolism was studied as evidenced by the sugar and pyruvic acid levels in blood and glycogen and pyruvic acid content of tissues in euthyroid, hypothyroid and hyperthyroid rats by giving insulin. Results show that in a normal thyroxine-excess insulin state, the rise in blood sugar was less, glycogenesis was much enhanced and glycolysis was reduced in comparison to these data in the euthyroid state. When thyroxine deficiency was associated with excess insulin, glycogenesis was enhanced further and an almost complete inhibition of glycolysis was observed. In excess thyroxine-excess insulin state glycogenesis was increased at the expense of glycolysis in comparison to the finding in the hyperthyroid state. Thus exogenous insulin in the euthyroid state altered the pattern of carbohydrate metabolism enhancing glycogenesis and inhibiting glycolysis. In a low thyroxine-excess insulin state, further enhancement of glycogenesis and inhibition of glycolysis were observed. But in an excess thyroxine-excess insulin state, the higher thyroxine activity was somewhat neutralized by higher insulin action allowing glycogenesis with glucose to proceed to some extent.

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To Clarify the relationship between the time interval and pituitary Luteinizing hormone (LH), Follicular stimulation hormone (FSH) and prolactin (PRL) secretion function under LHRH-TRH stimulation, 4 mature female baboons were used. Two consecutive LHRH (100μg)-TRH (250μg) stimulations with a 60min interval between them was carried out in the early follicular phase, late follicular phase and mid luteal phase in the same baboon in the first menstrual cycle, then carried out with a 120min interval between tests in the third menstrual cycle. The LH, FSH and PRL were measured by specific radioimmunoassay.
The PRL maximum response to the first bolus of TRH was higher than maximum response to the second bolus of TRH. The PRL maximum response to the second TRH at a 120min interval was higher than the maximum response to the second TRH at a 60min interval. It seems that the TRH had the dominant effect on PRL releasing but not on PRL Priming.
The maximum LH response to the second bolus of LHRH was higher than the maximum response to the first bolus of LHRH. The LH maximum response to the second bolus of LHRH at a 60min interval was greater than the maximum response at a 120 min interval in the follicular phase but it was the reverse in the luteal phase. The FSH response to the second LHRH was different from the LH response. The FSH maximum response to the second bolus of LHRH in 120min was greater than the maximum response to the second bolus of LHRH at a 60 min interval in all phases of menstrual cycle. It seems that the longer time interval does not favor the LH response or priming effect, but does favor the FSH in this study.

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The two kinds of glycoprotein hormone α subunit ectopically produced by an undifferentiated carcinoma of the left femoral region (TM-α) and an adenocarcinoma of the right external genitalia (FS-α) were examined for amino acid composition, isoelectric focusing, molecular weight, the ability to combine with standard hCGβ and affinity with lectins (Con A, Ricin and PNA). Both TM-α and FS-α exhibited immunoantigenicity similar to standard hCGα. Furthermore, there were no significant differences in the amino acid compo-sitions of TM-α, FS-α or standard hCGα. In isoelectric focusing, while standard hCGα exhibited a neutral charge, both TM-α and FS-α exhibited strong negative charges. FS-α was as sensitive to sialidase as standard hCGα, whereas most of the TM-α exhibited resistance to sialidase. TM-α contains sialidase-insensitive peripheral material with a negative charge. The affinity with Ricin-Sepharose indicated that most of the FS-α and some of the TM-α may contain terminal sialic acid and the penultimate structure, Galβ1→4GlcNAc; the affinity with PNA-Sepharose indicated that both may also contain terminal sialic acid and the penultimate structure, Galβ1→3GalNAc.
These observations suggest that dissimilar glycosylation processes are present in the carcinoma ectopic biosynthesis of glycoprotein hormone α subunit.

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Secrepan (Eisai Co. Tokyo, Japan) was administered to 9 healthy volunteers and 36 patients with non-insulin dependent diabetes mellitus (NIDDM) to clarify the effect of secretin on the pancreatic B-cell, by determining the changes in blood of insulin (IRI). Whereas IRI in healthy subjects showed a monophasic change, reaching a peak (ΔIRI=43±7.3μU/ml, M±SE) 5min after secretin loading and returning to the basal level in 15min, NIDDM patients on diet therapy (ΔIRI=40.2±7.6μU/ml) showed no significant difference from the con-trol group, but NIDDM patients on sulfonylurea (SU)(15.5±2.4μU/ml) and those on insulin therapy (5.3±1.4μU/ml), both showed a significant depression in responsiveness. Further, the changes in insulin secretion after atropine ad-ministration in healthy subjects and the changes in IRI response to Secrepan in vagotomized patients were also determined. As a result, data which pre-clude the possibility of association of the vagus nerve and cholinergic nerve with the stimulation of insulin secretion by secretin were obtained, and a direct action of secretin on the cell of islets of Langerhans was suggested.
The maximum IRI response after a secretin load had a significant positive correlation with the IRI response after a 75-gm GTT and the content of C-peptide immunoreactivity in 24-hour urine. Therefore, insulin response to a secretin load can be useful in assessing endogenous insulin secretion and pro-vides a pertinent clinical guide for the selection of an appropriate therapy for diabetes mellitus.

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We investigated the effect of thyroid hormone on phosphatidylinositol-specific phospholipase C activity in rat liver. Thyroidectomy increased the activity of the enzyme. Thyroid hormone (T4, 40μg) administration to thy-roidectomized-rats decreased phospholipase C activity. The inhibition inducedby thyroid hormone was of a non-competitive type. The higher concentration of Ca²⁺ strongly inhibited the activity of the enzyme obtained from thyroidecto-mized-rats' liver in vitro. The diminished activity of the enzyme obtained from thyroxine-treated-thyroidectomized-rats was recovered by pretreatment of the enzyme with EGTA. The activity of the enzyme derived from thyroidectomized-rats was not affected by EGTA treatment.
These results suggest that thyroid hormone decreases the activity of phos-phatidylinositol-specific phospholipase C activity through the mobilization of Ca²⁺ in the intracellular space.

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Effects of ethanol and acetaldehyde on the release of arginine-vasopressin (AVP) and oxytocin (OXT) were examined using a superfusion system of the isolated hypothalamo-hypophyseal complex of rats. The release of both hormones was significantly suppressed by exposing the tissue samples to Eagle MEM medium containing 1.75 and 2.5% ethanol (the maximal suppression: AVP, 30% and 70%; OXT, 30% and 70%, respectively). However, perfusion with medium containing 3.75 and 5.0% ethanol enhanced the release of OXT during exposure to ethanoi (the maximal increase, 1, 000%) and the release of AVP was increased markedly just after exposure to ethanol was stopped (the maximal increase, 800%). Perfusion with medium containing 50, 100 and 250μM acetaldehyde did not affect the release.

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A leukocyte migration inhibition test on the human pancreatic B-cell clone (JHPI-1) was performed in 13 IDDM patients with islet cell cytoplasmic antibody (ICCA) and/or islet cell surface antibody (ICSA), 15 IDDM patients without ICCA or ICSA, 34 NIDDM patients and 17healthy controls. The mean values for the migration index (M.I.%) in each group were 85.4±6.9, 89.1±10.9, 98.3±7.9 and 100.0±8.5. The M.I. values were significantly decreased in IDDM patients than in NIDDM patients and controls irrespective of whether or not there were islet cell antibodies in the patients' sera. When M.I. values less than 0.83 (Mean-2 S.D.) were taken as indicative of inhibition, the percentage of IDDM and NIDDM patients with migration inhibition were 32% and 0% respectively. And the decreased M.I. values in IDDM patients proved not to be due to non-specific migration inhibition by normal M. I. values, with the human fetal lung fibroblast cells (W138) as antigen. Our data suggested that the lymphocytes of IDDM patients might be sensitized by pancreatic B-cell antigen (s) present in the JHPI-1 cells, which promoted leukocyte migration inhibition. No correlation between the migration indices and duration of diabetes mellitus in IDDM patients was observed (r=0.254, Y=84.9+0.49X). LMT to JHPI-1 seems to be useful in detecting the abnormal cell-mediated immunity even in patients with longstanding IDDM.

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After a large amount of aldosterone was injected into a male rabbit, urine was collected for 48h. Separation of urinary aldosterone metabolites into monoglucosiduronate fraction and monosulphate fraction was carried out by a combination of countercurrent distribution and DEAE-Sephadex A-25 column chromatography. Each fraction was hydrolyzed with enzyme and free steroids released were separated by Sephadex LH-20 column chromatography. The free steroid was then identified by gas chromatography-mass spectrometry.
In monoglucosiduronate fraction, 3α, 5β-tetrahydroaldosterone and 3α, 5β-tetrahydroaldosterone were found. On the other hand, 3α, 5β-tetrahydroaldosterone was the only aglycone detected in monosulphate fraction.
These findings comfirmed results in the preceding paper, where the free steroid was characterized on the basis of the mobility of the steroid and its derivatives on paper chromatography.

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A 12-year old girl was admitted to our hospital for evaluation of her short stature. Her height was below -3.5 SD of the mean height for her age. She was diagnosed as having craniopharyngioma and treated surgically. Thereafter she was treated with thyroxine and hydrocortisone. One and a half years later, she revisited our hospital for treatment of short stature. Her plasma GH did not respond to insulin-induced hypoglycemia but increased after hGRF-44 administration, indicating hGRF deficiency. hGRF was therefore administered at a dosage of 100μg twice a day subcutaneously for three months. Her height increased 1.6 cm during treatment, which corresponded to a height increase of 6.4cm/year.
These findings indicate that hGRF treatment stimulates height increase in patients with GRF deficiency. For complete evaluation of hGRF therapy, further studies will be required.

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The present study was performed to investigate whether or not there were enkephalins in plasma and urine in normal subjects and in patients with various diseases.
Two kinds of antisera were developed to detect M-enk and L-enk. One has specific affinity with the C-terminus of methionine-enkephalin sulfoxide (M-O-enk), the oxidized form of M-enk, and the other with the N-terminus of L-enk. M-enk-like substance (MELS) was present in blood and urine in normal subjects, but not L-enk-like substance (LELS). Plasma MELS and its urinary output averaged 38±14pg/ml (N=19) and 605±235mg/day (N=15, M.±S. D.), respectively. There was a significant increase in plasma MELS and its urinary output in patients with pheochromocytoma. Plasma MELS did not show any significant increase or decrease in Cushing's disease, Addison's disease, panhypopituitarism or chronic glomerulonephritis. The urinary output of MELS was significantly increased in patients with essential hypertension, renovascular hypertension and primary aldosteronism, but was decreased in central diabetes insipidus.

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The effect of prostaglandin E (PGE) on aldosterone release and the mechanism of action of PGE in mediating the release of aldosterone were studied using isolated rat glomerulosa cells. PGE₁ stimulated aldosterone release in a dose-dependent fashion at concentrations between 10^-8 and 10^-6M and caused approximately a two-fold increase over the basal aldosterone level at 10^-6M. A significant and dose-dependent increase in cAMP production was also produced by PGE₁ at concentrations greater than 10^-8M. Aldosterone release induced by 10^-7M or 10^-8M PGE₂ was significantly reduced by a competitive receptor blocking PG-antagonist, SC 19220 (10^-7M), but not affected by (Sar¹, Ileu⁸)-angiotensin-II (A-II), a competitive inhibitor of A-II. PGE-stimulated aldosterone release was almost completely abolished by depleting the extracellular Ca²⁺ by EGTA, or by verapamil, a Ca²⁺-channel blocker or W-7, a calmodulin inhibitor.
These findings suggest that PGE stimulates aldosterone release through the membrane receptor binding and activation of adenylate cyclase and that Ca²⁺- calmodulin system plays an essential role in mediating the steroidogenic action of PGE in the adrenal glomerulosa cells. However, the physiological significance of PGE in the regulation of aldosterone secretion remains to be elucidated.

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The effect of castration and replacement therapy with testosterone propionate (TP) on the pituitary LH concentration and contents in the house musk shrew was investigated by using an in vitro bioassay for LH, the Rat Interstitial Cell Testosterone assay. The concentration and contents of LH increased slightly 10 days after castration, but decreased progressively thereafter to about a half of the pre-operation level by 90 days after the operation. The replacement with TP (100μg/day) for 7 days significantly depressed LH contents when it was begun 10 days after castration, while the same treatment started immediately after or 30 days after the operation did not significantly affect the pituitary LH level. The feedback mechanism between the gonad and the pituitary may be slightly different in the shrew from that in other mammals.
TP replacement, started immediatly after castration, completely inhibited the decrease in the weight of male accessory sex organs in castrated shrews. In castrated animals when more than 10 days had elapsed after the operation, however, the decreased weight of the organs could not be fully restored by the TP replacement for 7 days.

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In order to elucidate the mechanism (s) responsible for the prolonged antidiuretic activity of 1-deamino-[8-D-arginine]-vasopressin (dDAVP), antidiuretic activities of dDAVP and arginine vasopressin (AVP) were determined in the rat following either oral administration or incubation with AVP-degrading enzymes and reagents. Oral administration of dDAVP to conscious waterloaded rats resulted in significant antidiuresis while AVP resulted in slight and transient antidiuresis. In the ethanol anesthetized water-loaded rats, antidiuretic activities of 136pg of AVP and 50pg of dDAVP, which were found to be equipotent, were compared after incubation with digestive enzymes (pepsin, trypsin, α-chymotrypsin), late pregnancy plasma, or sodium thioglycollate. The antidiuretic activity of AVP was completely destroyed by 30-min incubation with trypsin, α-chymotrypsin, or late pregnancy plasma and almost all AVP was inactivated by 0.2M sodium thioglycollate. On the other hand, the antidiuretic activity of dDAVP was not destroyed by trypsin or pregnancy plasma but was partly destroyed by α-chymotrypsin and sodium thioglycollate. Neither the antidiuretic activity of AVP nor that of dDAVP was affected by pepsin. Thus, the antidiuresis observed after oral administration of dDAVP might be brought about by the resistance to digestive enzymes. Furthermore, the resistance of dDAVP to digestive enzymes, late pregnancy plasma and sodium thioglycollate might be responsible for the prolonged antidiuretic action of dDAVP in vivo.

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This paper aims to investigate the growth hormone (GH) responses to the growth hormone releasing factor-44 (GRF-44) in young and adult rats in vitro and in vivo. Male Wistar rats aged 28 days and 6 months were used. In pentobarbital anesthetized young rats, an intravenous administration of GRF-44 at a dose of 25ng/100g b. w. resulted in an 11.4 fold rise in the serum GH level at 5 min after GRF-44 injection. On the other hand, in adult rats the same dose of GRF-44 did not elicit a significant rise in the serum GH level. However, GH secretion in response to GRF-44 at a dose of 250ng/100g b. w. was not attenuated in adult rats. Isolated pituitary cells obtained from young and adult rats were incubated for 3 days. The addition of GRF-44 at a concentration of 5ng/ml to the cultured pituitary cells from young rats caused a 3.2 fold increase in GH content in the medium. On the other hand, the same dose of GRF-44 added to the cultured pituitary cells from adult rats resulted in only a 2.3 fold increase in GH content. These data indicate that the sensitivity of somatotrophs to GRF may be diminished with age.

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In a sensitive ACTH bioassay system using isolated rat adrenal cells, we tested the effect of γ-MSH related peptides on ACTH-induced steroidogenesis. Peptides, including synthetic γ1-, γ2-, γ3- and Lys-γ3-MSH, exerted no effect in augmenting ACTH-induced steroidogenesis. None of the 16 kilodalton fragment of ACTH/β-lipotropin precursor and its cleaved fragment had such an activity. The results are in contrast with previous reports concerning ACTHpotentiating activity of γ-MSH related peptides and, therefore, indicate the necessity of further investigation of the principle involved in this unique biological activity.

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The relationship between thyroid plasma membrane phosphorylation and thyrotropin (TSH) receptor degradation was investigated by using bovine thyroid tissues. By fractionation of thyroid cytosol (105, 000×gsupernatant of thyroid homogenate) in a continuous sucrose density gradient centrifugation, three different TSH binding activities were separated. During the incubation of thyroid plasma membranes, TSH binding activities were spontaneously released in vitro. By fractionation of the fraction containing released TSH binding activities in the same sucrose density gradient centrifugation, three different TSH binding activities were isolated. These peaks of TSH binding activity corresponded to the peaks of TSH binding activity obtained in cytosol fraction. Adenosine 3', 5'-monophosphate (cyclic AMP) enhanced the release of TSH binding activities from the plasma membranes in vitro. After fractionation on a sucrose density gradient centrifugation of the supernatant of the plasma membranes which were preincubated with cyclic AMP, three different peaks of TSH binding activity were identified. These peaks corresponded to the peaks obtained in spontaneously released TSH binding activity. In this case, however, the amount of small molecule TSH binding activities was predominant compared to that of large molecule TSH binding activity. During the incubation of the plasma membranes with [r-³²P]-ATP and with cyclic AMP, phosphorylated soluble proteins were released. The profile of the phosphorylated soluble proteins in the sucrose density gradient centrifugation showed three different peaks which corresponded to the peaks of binding activity.
The results suggest that cyclic AMP-dependent phosphorylation of thyroid plasma membrane degrades TSH receptor to small molecule TSH binding activities in soluble forms, and that these small molecule TSH binding activities may be accumulated in the cytoplasma of the thyroid. Further, it is also suggested that the released soluble TSH binding activities may be present as substrate for cyclic AMP-dependent protein kinase in the plasma membrane.

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ACTH responsein vivoand in vitro to synthetic ovine corticotropin-releasing factor (o-CRF) was examined in a bronchial carcinoid from a patient with ectopic ACTH syndrome. o-CRF, 1μg/kg iv bolus, scarcely increased plasma ACTH or cortisol on one occasion, but they showed a low response on retesting. On the other hand, 10^-8and 10^-7M of o-CRF significantly stimulated ACTH release in cultured bronchial carcinoid cells.

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