Molecular size heterogeneity of immunoreactive prolactin (PRL) in sera of pregnant women and patients with PRL-secreting pituitary tumor as well as pituitary tumor extract was investigated. “Big big PRL” in the vicinity of the void volume was identified by PRL radioimmunoassay. The ratio of “big big PRL” to “little PRL” was almost constant in normal pregnant women, while the proportion varied from case to case in patients with pituitary tumor. The ratio of “big big PRL” to “little PRL” was significantly (P<0.01) larger in these patients (43.3±9.8%, mean±SE) than in pregnant women (13.0±0.77%). Neither radiation therapy nor thyrotropin releasing hormone (TRH) stimulation significantly affected the ratio of “big big PRL” to “little PRL”, while it decreased from 20.5% to 9.5% one month after tumor resection. The elution patterns of the normal human pituitary extract and the tumor extract obtained from patients with PRL-secreting pituitary tumor revealed peaks in identical positions, although the ratio of “big big PRL” to “little PRL” in the tumor extract (38.2±3.6%) was significantly (P<0.01) larger than that in normal human pituitary extract (5.8±2.8%). These results indicate that “big big PRL” is present in sera of pregnant women and patients with PRL-secreting pituitary tumor, normal pituitary extract and tumor extract. It is also suggested that the increased circulating “big big PRL” observed in patients with PRL-secreting tumor may originate in tumor tissue.

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Since atrial natriuretic factor (ANF) has been shown to inhibit vasopressin secretion, the role of this effect in the acute biological actions of ANF was investigated using Brattleboro-strain diabetes insipidus (DI) rats. Under thiobarbital anesthesia, synthetic rat ANF of a25amino acid sequence was administered intravenously as a bolus (8μg/kg) into the jugular vein. The urine volume, urinary sodium and potassium concentration, blood pressure, and heart rate were determined. It was found that ANF administered exo-genously can exhibit its diuretic, natriuretic and vasorelaxant activities even in the absence of vasopressin. This indicates that the inhibition of vasopressin secretion is not an indispensable mechanism for acute biological effects of ANF.

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Specific insulin-like growth factor I (IGF-I) receptors on the Madin-Darby canine kidney (MDCK) cell line were identified and characterized.[¹²⁵I] IGF-I specifically bound to the cells, but [¹²⁵I] insulin bindings to the cells was minimal. Unlabeled IGF-I displaced both the IGF-I and insulin bindings with potencies that were100 and 10 times as great as insulin. By an affinity labeling technique, IGF type I receptors were present in the MDCK cells. IGF-I stimulated DNA synthesis and cell proliferation at physiological concentrations. On the other hand, insulin had a little effect on DNA synthesis. These data suggest that IGF type I receptors as demonstrated in MDCK cells are involved in DNA synthesis and cell proliferation.

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The characteristics of adjuvant-induced pouch granuloma in genetically diabetic KK-CA^y mice with hyperinsulinemia were investigated. Both the dose-response relationship and the time-course experiments showed that the wet weight of pouch granuloma in diabetic KK-CA^y mice was lower than in ddY normal mice. Insulin treatment enhanced granuloma formation in KKCA^y mice, and it restored the suppressed DNA content in the granuloma tissue to the level in ddY mice. Although the DNA content was dosedependently increased by insulin, the ratio of DNA content to granuloma weight was constant. In severely diabetic mice, the granuloma weight was not different from that in normoglycemic mice, despite significantly higher blood insulin levels and greater body weight. Insulin stimulated granuloma formation in severely diabetic KK-CA^y mice only when higher doses (1mg/kg) were given. This evidence suggests that suppression of granuloma formation in diabetic KK-CAy mice is due to insulin resistance and that restoration requires pharmacological doses of insulin.

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The thyroid function and antithyroidal antibody were studied in17patients with silent thyroiditis unrelated to pregnancy. The antimicrosomal hemagglutination antibody (MCHA) was negative in ten of them (group I) and was positive in seven (group II). At one month after the thyrotoxicosis, thyroid function became normal in both groups. At two months after the onset of thyrotoxicosis, in group I T₄ (8.1±1.8μg/dl, Mean±SD), T3 (113±25ng/dl) and TSH were normal. At that time T₄ (2.8±2.2μg/dl) was significantly decreased (p<0.001) compared with those of group I and the levels of TSH were strikingly increased in6patients in group II. The level of T₃ (96±29 ng/dl) in group II was not different from that of group I. Therefore MCHA was negative in patients who did not develop hypothyroidism and MCHA was positive in patients who developed hypothyroidism. The development of hypothyroidism two months after thyrotoxicosis and positive MCHA are correlated.
The Tg was elevated in7out of13patients (54%) with negative antithyroglobulin hemagglutination antibody and in the remainder was normal during thyrotoxicosis. The discrepancy between the level of Tg and thyroid hormones was discussed.

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Specific insulin-like growth factor I (IGF-I) receptors on human promyelocytic leukemia cell line (HL-60) were identified and characterized.[¹²⁵I] IGF-I specifically bound to the cells, and PIJIGF-I binding to the cells was displaced by unlabeled IGF-I in a dose dependent manner.[¹²⁵I] IGF-I binding to the cells were displaced by multiplication stimulating activity (MSA) and porcine insulin, with potencies that were10and100times less than that of IGF-I, respectively. By an affinity labeling technique, IGF type I receptors were found to be present on the HL-60cells.
After the cells were differentiated to the macrophage-like cells by 12-o-tetra-decanoyl-phorbol-13-acetate (TPA) and1, 25-dihydroxy-vitamin D₃ (1, 25 (OH) ₂D₃), [¹²⁵I] IGF-I binding to the cells decreased significantly. By Scatchard analysis, it was found to be due to a decrease in the number of IGF-I receptors.
Thus, the differentiation of HL-60cells to the macrophage-like cells was accompanied by a decrease in IGF-I receptors.

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DNA samples from five unrelated Japanese patients with21-hydroxylase (21-OHase) deficiency were studied by Southern analysis using human21-OHase cDNA. Patterns seen after digestion with not only TaqI but also KpnI showed that two out of the five patients were homozygous for a deletion of the21-OHase B gene. This result supports the report that the21-OHase B gene is functional. In the other three, smaller mutations might be responsible for the disorder. The parents of one of the two patients with the deletion had a common ancestor. Hybridization patterns of DNA from members of the family of the patient were consistent with an autosomal recessive mode of inheritance of the deletion that correlates with the clinical phenotype. The deletion segregated with HLA-Aw24; Bw61; Cw3. Heterozygous carriers of21-OHase deficiency could be detected by comparing the patterns as well as the HLA haplotypes in this family. The application of the family study to the prenatal diagnosis is also discussed.

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Female Wistar-strain rats were starved for14-19days by feeding approximately1/4of the amount consumed by ad libitum fed controls. The body weight was reduced by41% and the heart weight by38% in these starving periods. The ¹²⁵I-iodocyanopindrol (ICYP) binding capacity of heart preparations from the starved rats was35.3±11.1 (mean±SD) fmol/mg protein in comparison with 69.3±14.9for the controls. Serum3, 5, 3'-triiodothyronine (T₃), thyroxine and TSH levels as well as pituitary TSH contents were markedly lower in the starved rats. One group of them further received 20ng of T₃ daily after the 8th day of the experiment. The body weight decreased by 47% of the controls but the ICYP binding capacity recovered to 56.3±10.9fmol/mg protein. There was no difference in association constants of the receptors in these three groups. It was concluded that quasi-chronic starvation in rats caused a remarkable decrease in the number of β-adrenergic receptors in heart and this was partly offset by the substitution of T₃.

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Studies were carried out on the role of vasoactive intestinal polypeptide (VIP) in the regulation of secretion and blood flow in the rat salivary gland. The first experiments to investigate the spontaneous secretory pattern revealed a clear diurnal fluctuation with a significant increase at night, so that the subsequent experiments were performed during the daytime where the secretion was consistently low.
Intravenous administration of VIP at a dose smaller than40pmole caused a dose-dependent vasodilatory response, but at a high dose such a local effect was hampered by a decrease in systemic blood pressure. VIP potentiated the acetylcholine chloride (AcCho)-evoked salivary secretion, but VIP (0-100pmole/kg) alone did not cause salivary secretion.
Atropine reduced the salivary secretion evoked by AcCho and VIP, and the blood flow change evoked by AcCho. However, the blood flow change evoked by VIP was not affected by atropine. Hexamethonium exerted no significant effect on the response to administration of AcCho or VIP. The results indicate that VIP has a significant vasodilatory action and cooperates with AcCho in the regulation of salivary secretion in the rat, and VIP effects are atropine resistant, as in other species of animals.

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Intravenous GnRH pulsatile infusion therapy (10μg/pulse, 90-min interval) was conducted in an acromegalic patient from whom 2/3 of a GH-producing pituitary macroadenoma had been removed. Before infusion therapy, plasma levels of GH and PRL were 10-20 and 15-25 ng/ml, respectively, while those of LH and FSH were subnormal without intrinsic fluctuations. Ovulation was induced after 13 days of infusion which was terminated on the 23rd day of therapy. Luteal function was supported by hCG (5, 000 IU per dose) which was given 4 times from the 23rd to the 31st day of the treatment cycle. Triplet pregnancy was diagnosed ultrasonographically within 7 weeks of gestation. Although GH and PRL levels increased gradually as the gestational period progressed and plasma levels of GH and PRL of 32-55 and 30-67 ng/ml, respectively, were detected after 30 weeks of gestation, neither adverse signs related to the enlargement of the residual pituitary tumor nor manifestation of acromegaly was observed. The immunoreactive somatomedin-C levels during this period were not greater than those in normal pregnant women. Caesarian section was performed at 34 weeks and 3 normal healthy infants were delivered.
Detailed analyses of hormonal changes throughout the period of GnRH pulsatile infusion and subsequent luteal phase revealed that the triplet pregnancy had been induced by the GnRH therapy itself and that hCG stimulation did not play any critical role. The residual tumor mass secreted increasing amounts of GH during the latter period of pregnancy but the somatomedin-C levels were not associated with this elevation. Therefore, the clinical as well as the hormonal findings strongly suggested that the GH secreted in increasingly large amounts by the residual tumor mass during pregnancy was defective in certain biological properties.

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Thyroid peroxidase (TPO) located in the apical plasma membrane of follicular cells was investigated by means of a membrane-immunofluorescent technique. The epitope of TPO recognized by a murine monoclonal antibody (mAb 30.1.2) was identified on the apical membrane surface. Trypsinization removed TPO immunoreactivity and enzymatic activity after 60min of incubation at37°C. The epitope reappeared on the apical membrane surface after short term culture for 120min without the addition of TSH. With TSH the time required for reappearance was only 30min. TPO activity was regenerated under both conditions. Since dibutyryl cyclic AMP could not accelerate the reappearance of the epitope, it was thought that TPO reappearance is mediated by other than the adenylate cyclase-cyclic AMP system.

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We have examined changes in plasma ketone bodies and their related metabolites after the ingestion of a mixed meal in normal and NIDDM (non-insulindependent diabetes mellitus) using a highly sensitive colorimetric method. In normal subjects, fasting plasma acetoacetic acid (AcAc) and 3-β-hydroxybutyric acid (3-OHB) concentrations were 40.2±2.9 and 21.3±4.0μM, respectively. The total carnitine level in fasting plasma was 48.2±3.2μM and acyl/free was 0.34±0.12. These values did not change significantly after the meal. In diabetic subjects. fasting AcAc and 3-OHB levels were 57.9±3.5 and 97.9±14.7μM, respectively and these values especially 3-OHB, decreased almost to the normal level by 4h after the meal. The total carnitine level in the tasting plasma of diabetics was 48.7±2.8μM and acyl/free was 0.58±0.09. Such characteristics were observed when their plasma glucose had been completely normal for more than 10days. In patients treated with sulfonylurea, the fasting ketone body level, especially 3-OHB, was significantly lower than that of diabetics treated with insulin or diet alone, whereas the fasting plasma glucose level and its postprandial increase were higher than those of the others. These results demonstrate that measurement of the plasma ketone body (especially 3-OHB) level is a sensitive tool for monitoring the metabolic status of NIDDM.

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Rat growth hormone releasing factor (rGRF)-and somatostatin (SRIF)-like immunoreactivities (LI) were determined by radioimmunoassay in the medial basal hypothalamus (MBH) of the rat with either complete deafferentation (CD) or a sham operation. Two weeks after the surgery the mean amount of SRIF-LI in the isolated MBH was about 70% less than that in the shamoperated animals. On the other hand, the mean rGRF-LI in the MBH decreased only approximately 30% as compared to the levels in the sham-operated animals, the difference being statistically insignificant. These findings are consistent with anatomical evidence that the majority of the GRF perikarya are located in the arcuate nucleus, but a few are found outside the MBH, whereas the majority of the SRIF perikarya are located outside the MBH.

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We report on three adult cases of acute suppurative thyroiditis due to infection through a piriform sinus fistula. In these cases, the lesion did not exhibit the clinical symptoms characteristic of acute suppuration, but appeared as an unusual neck mass. Repeated barium meal roentgenograms, however, demonstrated the internal fistula in two of the three cases. Acute suppurative thyroiditis may not be so rare even in adults. When acute suppurative thyroiditis occurs in adults with scanty symptoms of acute suppuration, the piriform sinus fistula could easily go undetected. Recognition of acute suppurative thyroiditis in adults per se seems to be important for correct diagnosis.

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The internalization of FSH-receptor complexes was demonstrated in mouse testis by means of light and electron microscopic autoradiography Chopped testicular pieces were incubated with radioiodinated FSH (¹³¹I-NIADDK-rat FSH-I-4) for 10, 20, 60 and 180 min. After incubation the pieces were fixed with glutaraldehyde containing tannic acid, and embedded in Spurr's resin. Semithin and ultrathin sections were cut for light and electron microscopic autoradiography, respectively. In light microscopic autoradiographs, silver grains were preferentially localized over Sertoli cells, regardless of incubation time. Sixty to 70% of the total number of grains were located over Sertoli cells which account for only about 4% of the total cell population of the seminiferous tubules. The majority of these grains correspond to the specific FSH binding sites, because few grains remained after incubation with an excess amount of unlabeled FSH. In electron microscopic autoradiographs, the halfdistance (HD) value for the ¹³¹I-labeled line source was about 216 nm in the present study. After 10 min of incubation, 56.6% of the total number of silver grains were located over the plasma membrane of Sertoli cells. In testicular pieces incubated for longer periods (20, 60 and 180 min), both the percentage and relative concentration of grains increased in the Golgi apparatus and lysosomes and decreased in the plasma membrane. These results suggest that [¹³¹I] iodo-FSH first binds to FSH receptors on the plasma membrane of Sertoli cells, then FSH-receptor complexes are internalized. The increase in the number of grains over the lysosomes following longer incubation, indicates that internalized [¹³¹I] iodo-FSH or FSH-receptor complexes are subjected to degradation.

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The effects of the intranasal administration of synthetic alpha-human atrial natriuretic polypeptide (alpha-hANP) were investigated in14anesthetized spontaneously hypertensive rats (SHR; Okamoto-Aoki strain). They were given intranasally synthetic alpha-hANP in distilled water at doses of 10μg/kg, 50μg/kg and 100μg/kg. Intranasal application of 200μl of distilled water as a control was also performed in 3 anesthetized SHR. Sixteen anesthetized SHR were examined for the effects of intravenous administration of alpha-hANP at doses of 4μg/kg, 10μg/kg, 20μg/kg and 40μg/kg.
Urinary volume and the urinary excretion of sodium increased 2- to 3-fold during the 50minutes following intranasal administration of a single dose of 50μg/kg or 100μg/kg, although neither the urinary volume nor the urinary excretion of sodium increased after intranasal administration of 10μg/kg of alpha-hANP or 200μl of distilled water. There were no significant changes in arterial pressure or heart rate after the intranasal administration of synthetic alpha-hANP or distilled water. In contrast, arterial pressure was decreased and urinary volume and urinary excretion of sodium were increased, in a dose dependent manner, within 5minutes after intravenous bolus-injection of alpha-hANP and returned to their baseline levels within 20minutes.
These results indicate that intranasal administration of synthetic alpha-hANP exerts its diuretic effect without concomitant changes in arterial pressure or heart rate in SHR.

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A 29-year-old nullipara was admitted at 31weeks' gestation because of toxemia. She noted gradually polyuria, severe thirst, malaise, nausea and anorexia. A water-deprivation test and administration of aqueous vasopressin confirmed the diagnosis of nephrogenic diabetes insipidus. At 33weeks' gestation, blood chemistry studies revealed moderately elevated transaminase levels and hyperuricemia. Male twins were delivered by vacuum extraction at 35weeks' gestation. After delivery, she became drousy and icterus appeared. Acute hepatic failure with marked hyperuricemia was diagnosed. She was treated with glucose solution with glucagon and soluble insulin, branched chain amino acids, gabexate mesilate, lactulose and famotidine. Her consciousness cleared rapidly and all laboratory data became normal by15days postpartum. The urine volume was about 5 liters per day from the first to sixth postpartum day. The diuresis decreased after the eighth postpartum day. Rare pregnancy complicated by transient nephrogenic diabetes insipidus and acute hepatic failure is discussed.

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