Postovulatory estrogen treatment has been shown to be an effective method for contraception in both women and monkeys. Recently postovulatory plasma LH peak has been observed in the normal menstrual cycle of the baboon. This study was designed to obtain information on the relationship between postovulatory LH and luteolysis. Blood samples and vaginal smears were obtained at 0800 hr daily in both control and treatment cycles of four adult female baboons. Plasma levels of estradiol, progesterone and LH were determined. In the treatment cycle, 300 μg of estradiol benzoate (EB) (Progynon, Schering) was given sc twice daily at 0800 and 1600 hr beginning the day after the expected day of ovulation and continuing for 5 days. Plasma levels of estradiol were maintained over 500 pg/ ml during the EB treatment period which exceeded the control preovulatory plasma estradiol peak (300-420 pg/ml) by about 400-600 pg/ml. The length of the luteal phase during the treatment cycle was shortened in one of the four baboons. In the control cycle both a preovulatory LH peak and a postovulatory (1-3 days following ovulation) LH peak were observed. In three of the four baboons, there was both an increase in the plasma LH concentrations and a premature decline in plasma progesterone concentrations during the EB treated luteal phase as compared to those during the control luteal phase. In one baboon, no change was observed in the plasma LH and progesterone levels as compated to the control levels. These findings suggest that estrogen in large doses during the postovulatory period may induce functional luteolysis, i.e. suppression of the steroidogenesis in the corpus luteum and that insufficient progesterone secretion may make the endometrium unprepared for implantation. Massive LH release by postovulatory estrogen treatment suggests that hypothalamic-hypophyseal axis may participate in the mechanism of this luteolytic effect in the baboon.

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We have developed a preparation of monolayer cultures of bovine parathyroid cells in order to elucidate the control mechanism of the biosynthesis and secretion of parathyroid hormone (PTH) at cellular level.
Dispersion of parathyroid cells was performed by stirring minced bovine parathyroid tissues in Hanks' BSS containing 0.3-0.5% collagenase at 37°C for 60 min. Dispersed cells were cultured at 37°C in MEM·Hanks' BSS containing 10% fetal calf serum and 15 mM HEPES. On the 5th day of the culture, the medium was replaced with 1% BSA·MEM·Hanks·HEPES buffer, and the cells were incubated with ³H-leucine or in the media containing various concentrations of calcium, magnesium, PGE₁, PGE₂ or DBcAMP. At the end of incubation, the cells were detouched and homogenized in 8M urea, 0.2 N HCL and 0.01 M cysteine solution. The isolation of proparathyroid hormone (ProPTH) and PTH was performed through the preparation of TCA-powder followed by CMC column chromatography. PTH in the incubation medium was determined by radioimmunoassay.
It was demonstrated that the monolayer cultures of bovine parathyroid cells were synthesizing ProPTH and converting it to PTH. The cultures exhibited linear secretion rates of PTH into the medium. The secretion of PTH was markedly increased by PGE₁, PGE₂ or DBcAMP in the range of 10^-7-10^-5M in the former and 10^-5-10^-3M in the latter, while calcium or magnesium changed secretion rate in the range of 0.3-4.4 mM.

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It is well known that testosterone, estradiol and progesterone have an influence on sexual behavior in mammals. The effect will occur via central action. On the other hand, sex hormones may often be related to mental excitation in men, and exposure to excess testosterone during the foetal period not only induces a deficit in sexual differentiation but also affects the development of emotional expression after birth.
In order to pursue the role of sex hormones in mental function, we tried first to examine, the metabolism of testosterone in the central nervous system and the effect of central acting drugs on this metabolism.

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Oxytocin has been known to be released by females during delivery or lactation, but it has physiological significance for males which, as might well be supposed, has not yet been made clear. We can conjecture that it has some use in wide scope homeostasis.
Some sudden unexpected natural deaths are essentially negatie with regard to classical autopsy findings and the true causes of such deaths can not be found even by employing both gross and microscopic examinations and toxicologic analyses. In the best of medico legal institutions the rate of negative autopsies ranges from 2 to 10 per cent of the total cases examined.
Typical diseases for which autopsy findings are negative are the Sudden Infant Death Syndrome (SIDS) and the Sudden Manhood Death Syndrome (SMDS). These are included as sudden unexpected natural deaths where the patients are outwardly healthy, the past histories, of patients are not predictive of death and the convincing causes of the deaths can not be found out by means of the conventional postmorten examinations. Attention, however, has not been paid to SMDS in Europe and in the U.S. as has been done in Japan.
In sudden unexpected natural deaths, there is little doubt that certain biochemical disturbances may be operating. However, these have not been identified as yet under the current status of our knowledge, but physiological and biochemical study promise to be fruitful areas of investigation in the future.
To examine how oxytocin corresponds to SMDS, I examined 151 cases of various sudden death (male 116, female 35), in the age range of from 20 to 81 and compared the weight of each human pituitary gland, knewing that female pituitary glands are heavier than those of males. But we must also investigate if there is any relation with cerebral swelling in agony.
With the Chicken Depressor Method, I examined oxytocic activities of 53 adult pituitary glands (male 36, female 17) and got the following results.
1) No significant difference of oxytocic activity in the human pituitary glands was discerned between males (7.42±0.86U/gland) and females (7.53±1.03U/gland).
2) The oxytocic activity is not determined by age, it is not decreased even at the advanced age of over seventy.
3) The oxytocic activity decreases only shortly 34 hours after postmortem.
4) From pituitary gland removed after death, I could not find if oxytocin has diurnal variation of biological rhythm, but this does not prove that it has not so long as the correct method of quantity of level in the blood is not completed.
5) The most prominent character found in the measurement of oxytocic activity using human pituitary glands, is that the amount of oxytocin release differs according to causes of sudden death. I noticed a significant difference between SMDS and the group of cardiac arrests by negative autopsy which has usually been classified into the former in Japan.
When the cause is SMDS, the oxytocic acitivity measures 3.99 ±0.60 U/gland, while it measures 10.33±1.20 U/gland when the casuse is cardiac arrest. The low level of oxytocic activity at SMDS closely resembles that of the group of brain death (4.03 ± 1.34 U/gland).
6) So two assumptions can be drawn. One is oxytocin from pituitary gland release is more for SMDS than cardiac arrest. The other is that low level oxytocic activity may be causes by the low storage unable to keep up the amount released in the pituitary gland by the amount synthesized at hypothalamus, as the amount of oxytocin stored in the pituitary gland being balanced between it is the amount synthesized and released.

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The present experiment was planned to verify the effect of calcium on adenyl cyclase in isolated human adrenal cells.
Normal adrenal glands were obtained surgically from patients with primary aldosteronism and advanced breast cancer. Isolated adrenal cells were prepared by the modified Haning's method. They were incubated at 37°C under a gas mixture of 95% O₂ : 5% CO₂ in calcium-free Krebs-Ringer bicarbonate buffer solution containing 0.2% glucose and 0.5% fatty acid-free bovine serum albumin, to which various doses of CaCl₂ or ACTH were added.
Thirty minutes later, cyclic-AMP was measured by cyclic-AMP assay kit (The Radiochemical Center, Amersham). 11-OHCS was estimated fluorometrically by the modified Silber's method after incubation for 2 hours
In the calcium-free incubation medium, productions of 11-OHCS and cyclic-AMP were negligible. In the concentration of 2.54 mM/L of calcium, 11-OHCS production increased with significant difference statistically, while the increase of cyclic-AMP production was not significant. In the concentration of 12.70 mM/L of calcium, however, cyclic-AMP production increased remarkably. When ACTH was added to the incubation medium containing 2.54 mM/L of calcium, productions of 11-OHCS and cyclic-AMP also increased remarkably.
These results indicate that adenyl cyclase of human adrenocortical cells is directly stimulated by calcium and sggest that calcium acts as the second messenger of ACTH.

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The preoperative identification of adrenal tumor is essential to determine the method of surgical operation. For this purpose, retroperitoneal pneumography, adrenal venography, determination of hormone concentration in adrenal venous blood, adrenal arteriography or adrenal scintigraphy has been used.
It was recently reported that ultrasonic tomography identified a pheochromocytoma 3 cm in diameter. So this study examined whether a smaller adrenal tumor could be visualized by this method or not.
Sonograms in this study were obtained with a Toshiba SSL-21A or SSL-51U unit with a P.Z.T. transducer 10 mm in diameter operated as a contact scanner at 2 MHz. Patients were examined in the prone position. This placed the suprarenal region closer to the transducer and also eliminated the interfering effect of a gas-filled bowel. Sonograms were obtained with sagittal scan along each renal axis through the suprarenal region. A series of scans was conducted at 0.5 mm intervals.
Ultrasonic tomography was taken in 10 normal subjects, 6 patients with essential hypertension, 10 patients with primary aldosteronism and a patient with Cushing's syndrome. In 9 of 11 patients with adrenal tumor it was taken by reference to the findings of adrenal venography and in the other 2 patients before adrenal venography was performed.
In the echograms of 10 normal subjects and 6 patients with essential hypertension, the suprarenal regions were filled with echoes and adrenal glands were not visualized as discriminative structures. In 9 patients with primary aldosteronism and a patient with Cushing's syndrome, adrenal tumors were visualized as a sonically homogenous suprarenal mass. In a case of primary aldosteronism the border between tumor and kidney was not visualized distinctly. The size of the adrenal tumors obtained surgically ranged between 1.0 cm and 3.0 cm in diameter.
In conclusion, there is a possibility that smaller adrenal tumors such as aldosteronoma also can be identified by ultrasonic tompgraphy in some instances.

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Recent experimental and clinical studies LH-RH and somatostatin were presented. Immunological approaches, such as determination of these hypothalamic hormones in the tissue and blood by RIA, immunohistochemical studies, and active or passive immunization of animals with LH-RH or somatostatin, provided much useful information on the physiological roles of these hormones. LH-RH has been found to be useful not only for diagnosis of various diseases but also for treatment of some type of hypogonadisms. Experimental data on somatostatin suggest a considerable potential for practical application of somatostatin in the clinical field. However, the possible suppressive effect of somatostatin on platelet aggregation should be seriously considered when it is used for clinical purposes.

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