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Forty-one healthy male volunteers received 9 egg yolks daily in addition to their ordinary meals for 14 days. Mean elevation of serum cholesterollevels was 21,6 mg per 100 ml (11.4%) of the initial level. Middle-aged men (40 to 45) showed more elevation of serum cholesterollevel than young men (18 to 20). After the first egg yolk fee ding period, 6 young men and 3 middle-aged men, whose serum cholesterol levels increased by more than 10%, were selected to examine the etfect of moctamide on dietary hypercholesterolemia. They were given a daily oral dose of 300 mg of moctamide during the second egg yolk feeding period of 2 weeks, which was started 4 to 8 weeks after the end of the first period. In the third period, they were given 150 mg per day of moctamide in the same way. Daily doses of 300 mg of moctamide completely inhibited the elevation of serum cholesterol, while 150 mg suppressed it significantly.

Hepatic cholesterol 7α-hydroxylation and cholesterogenesis were determined in vitro at various time intervals 6 hr after oral or intravenous administration to fasted rats. Glucose administration to fasted rats enhanced cholesterol 7α-hydroxylation as well as fatty acid or cholesterol synthesis in the liver, though significant changes were not demonstrated in the cholesterol content of liver and serum throughout the observed periods. Hepatic cholesterol synthesis increased 1 hr after oral glucose ingestion. On the other hand, cholesterol 7α-hydroxylation was stimulated 2 hr after oral glucose administration, with a lag phase of 1 hr following the induction of cholesterol synthesis. From the results of the experiments on the effect of glucose ingestion, it appeared that cholesterol 7α-hydroxylation was correlated with hepatic cholesterogenesis. Hepatic cholesterogenesis was decreased in triparanol-treated rats and was not stimulated by glucose administration. Triparanol did not affect cholesterol hydroxylation in the fasted state, but did abolish the stimulatory effect of glucose. Short-term feeding of a high-cholesterol diet, which suppressed hepatic cholesterol synthesis, stimulated cholesterol 7α-hydroxylation. Oral administration of glucose to cholesterol-fed rats still further accelerated hydroxylation. In rats with ligated bile ducts, hepatic cholesterogenesis increased 24 hr after bileduct ligation while hydroxylation decreased 24 hr after the operation but was stimulated after 72 hr. Glucose ingestion by these rats stimulated both cholesterol synthesis and hydroxylation. It is concluded that increased hepatic cholesterogenesis enhances cholesterol 7α-hydroxylase activity; this activity does not depend upon increased fatty acid or other lipid synthesis, altered bile flow or gastrointestinal factors. Increased dietary cholesterol intake also accelerates hydroxylase activity. These mechanisms may preserve homeostasis in the serum cholesterol level, and an altered balance between these two enzyme systems — anabolic and catabolic — probably induces a change in the size of the body cholesterol pool.

Mie's theory has been applied to colloidal sodium in NaCl. In the course of the calculation, the optical constants of metallic sodium are corrected for the size of the colloidal particles. The contributions of the electric and magnetic partial oscillations to the total extinction (spectra) are analized.A discussion is given by comparing the calculated results with the experimental spectra reported by several authors.

In either ad libitum or restricted feeding of the high cholesterol diet for 10 days, total plasma and liver cholesterol level of the diabetic rats were remarkably higher than those of the controls. The significant difference of the plasma cholesterol between control and diabetic rats was not observed in the groups fed the low cholesterol diet, while the liver cholesterol content was more in the diabetic rats than in the controls.The reduced biliary excretion of the total radioactivity in the diabetic rats was demonstrated using 4-14C cholesterol. Either the excretion of labeled cholic acid or cholesterol was also reduced in diabetic state, but the per cent of labeled cholesterol to total radioactivity in the bile of diabetic rats was larger than that of controls and the per cent of labeled cholic acid in the diabetic rats was less than that in controls.The production of expiratory CO2 following administration of 26-14C cholesterol in vivo was lower in the diabetic rats than controls, showing the decreased conversion rate of cholesterol to cholic acid in the diabetic rats.When labeled cholic acid was administered, excretion of the radioactivity from the bile fistula was not affected in diabetic rats and the conjugation pattern of the cholic acid with taurine and glycine was not altered. It suggests that the conjugation process of cholic acid with amino acid and excretion of cholic acid was little altered between control and diabetic rats.From these results it is concluded that the rapid progress of alimentary hypercholesteremia in the diabetic rats might be mainly accounted for the accumulation of cholesterol caused by the impairment of its conversion to cholic acid which delayed the excretion.

1. The influence of estradiol-17β on cortisol metabolism was studied in vitro using the rat liver homogenate and microsome fraction.2. It was found in the experiments using homogenates that β4-3-ketone reduction of cortisol was considerably increased following the addition of a given amount of estradiol-17β to the medium and this effect of estradiol-17β became more pronounced under an anaerobic condition or in the presence of potassium cyanide.3. The stimulatory action of estradiol-17β on cortisol metabolism and its relation to TPNH-generating system were investigated in the purified enzyme system (24, 000×g supernatant fraction). It was found that estradiol-17β was able to replace glucose-6-phosphate system and no effect of estradiol-17β was observed in the presence of TPNH. Similar stimulatory effect of estradiol-17β was noted on aldosterone metabolism.4. Experiments on estrogen metabolism in microsome fraction of the rat liver showed evidence that the addition of cortisol with TPN increased the production of estrone from estradiol-17β.5. The results obtained suggest that estradiol-17β acts as a hydrogen donor to TPN to increase the reduction of A-ring of cortisol.

To investigate the dichroic property of the Z 4 band, the experiment on the anisotropic bleaching was made. It was found that the symmetry axis of Z 4 center is parallel to direction and the Cole and Friauf's A model is in conformity with this symmetry. It was also found that there exists the same correlation in dichroism between F and Z 4 band as that between F and M band.

1) One case of primary aldosteronism was reported. Adenoma of the left adrenal was confirmed on operation.2) In incubation experiments, overproduction of aldosterone and corticosterone was noted in the adenomatous tissue while cortisol and cortisone were produced only small amounts.3) The non-adenomatous tissue of the removed adrenal produced aldosterone about 1/3 the adenomatous tissue, although it produced more than normal adrenal tissue. The production of corticosterone, however, was very low.4) When corticosterone-4-C14 was added to an incubation medium with slices of adenoma, biosynthetic conversion of the radioactive steroid to aldosterone was greatly enhanced, 5 times as much as in the non-adenomatous tissue. Thus, an autonomous increase of the activity of 18-hydroxylase is reasonably considered.5) Histologically, hyperplasia was found in zona glomerulosa of the nonadenomatous portion of the removed adrenal cortex, suggesting some stimulating factor which continuously promotes a secretion of aldosterone. The pathogenesis of primary aldosteronism was discussed from a viewpoint of a renal stimulating factor.

The dichroic properties of Z bands and their correlation to that of the F band have been studied on NaCi:Sr and KCl:Sr single crystals. From the experiment on the anisotropic bleaching, the Z 1 center was found to be a center of high symmetry in agreement with the result of paramagnetic resonance experiment. The Z 2 band showed dichroism when irradiated with [010] polarized light in the Z 2 or F band at room temperature, accompanying the dichroism of opposite sign in the F band. This is another example of the correlation in dichroism between two absorption bands as shown in the F - M system which has been found by Van Doorn and Haven. It is, however, questionable to simply decide the symmetry of the Z 2 center from the dichroism mentioned above, because in the case of KCl:Sr its peak position is shifted to shorter wavelength than the normal Z 2 band.

Glucose-cysteine, hydroquinone, adrenaline, ascorbic acid, aspirin and butazolidin inhibit both the reduction of Δ4-3 ketone and the degradation of the side-chain in the metabolism of hydrocortisone in vitro.PAS and myleran inhibit only the degradation of the side-chain of hydrocortisone.

Repeated oral administrations of ethanol to rats induced accumulation of cholesteryl ester, as well as triglyceride in the livers. The contents of free cholesterol and phospholipid in the livers were not changed significantly in the present experiment in which ethanol ingestions were repeated four times. Although in vitro esterification of cholesterol by particle fractions of the alcoholic fatty liver was not affected, hydrolysis of cholesteryl palmitate by the supernatant fraction of the liver homogenate was reduced when compared with those of the control group which was given water or isocaloric glucose. The results of in vitro esterification of cholesterol and hydrolysis of cholesteryl palmitate in the liver of the rats which were ingested with glucose were larger than those of the control rats which were given water.

Remarkable lowering of plasma cholesterol by oxandrolone administration was observed in the hypercholesteremic rats fed the high cholesterol diet but not in the rats fed the low cholesterol diet during the short experimental period. Tween 80 induced hypercholesteremia or diabetic hypercholesteremia was not prevented by oxandrolone.Although the bile amount of the rats with bile fistulae was not influenced by the hormone administration, the biliary excretion of cholic acid and cholesterol was increased in the hormone treated group. Excretion of the radioactivity into the bile after labeled cholesterol injection was accelerated by oxandrolone. When 26-14C cholestereol was injected into the animals, more radioactivity was found in expiratory CO2 of the oxandrolone treated rats than that of the controls. Influx of administered cholesterol from plasma to the liver was accelerated in the oxandrolone fed rats with bile duct obstruction, and outflux of endogenous cholesterol from the liver to plasma was also increased.Cholesterol was accumulated in the liver by oxandrolone treatment when cholesterol was given simultaneously with the hormone, but the decrease of the hepatic cholesterol contents after the interruption of cholesterol feeding was promoted by the hormone administration.Therefore, the main mechanism of the hypocholesteremic effect of anabolicsteroids is assumed to be both the acceleration of the shift of cholesterol from plasma to liver and secondary stimulation of cholesterol catabolism to bile acid.

Cholesterol esterification and cholesteryl ester hydrolysis were estimated in vitro using liver homogenates from rats with accelerated cholesterol metabolism. Cholesterol metabolism was stimulated by feeding a high cholesterol diet, biliary drainage, feeding a high cholesterol diet plus biliary drainage or by feeding a lecithin-enriched diet. In vitro addition of lecithin or cholic acid to the incubation medium was also examined. Feeding a high cholesterol diet to the rats for 7 days stimulated cholesteryl ester hydrolysis as well as cholesterol esterification in the liver. Cholesterol esterification in serum was not significantly affected under the present experimental conditions. Biliary drainage accelerated cholesterol esterification in rats that had been fed the stock diet. In cholesterol-fed rats, however, it stimulated cholesteryl ester hydrolysis in the liver. Cholesterol esterification in the serum of bile-fistula rats was not affected in either group. Although serum cholesterol esterification was markedly enhanced by feeding lecithin, hepatic cholesterol esterification was depressed. In vitro addition of lecithin either to serum or liver homogenates increased esterification. Hepatic cholesteryl ester hydrolysis was neither affected by lecithin feeding nor by the direct addition of lecithin to the incubation medium. In conclusion, accelerated cholesterol turnover does not always influence esterification or hydrolysis in the same way. These activities may depend on the form in which cholesterol is presented in excess, on the effector sites and on the kind of stimulation.

1. Effects of various steroid hormones on cortisol metabolism were examined in vitro by the screening test, with the supernatant of rat liver homogenate.2. Competition was observed in a reduction of Δ4-3 ketone between methyltestosterone and cortisol, metabolism of cortisol being greatly inhibited by methyltestosterone.3. Ethinyl-estradiol inhibited cortisol metabolism, showing a marked inhibition in the reduction of Δ4-3 ketone.4. Progesterone delayed a disappearance of the infused cortisol in dogs.5. It is concluded that metabolic regulation of steroid hormones in the liver constitutes an influential element in the homeostasis of steroid hormones.

The in vitro production of corticoids from human adrenals was studied in normal and pathological states such as Cushing's syndrome or primary aldosteronism.1. Hyperplastic adrenals of Cushing's syndrome produced a large amount of cortisone, cortisol and corticosterone. In the adrenal adenoma of primary aldosteronism, the production of aldosterone and corticosterone was stimulated. Hyperplastic tissues of the adrenal, combined with adenoma, also produced relatively large amounts of aldosterone. Another case of primary aldosteronism without adenoma produced not only aldosterone but also cortisone, cortisol and corticosterone in large amounts.2. When ACTH was added to the incubation medium, the production of every kind of corticoids determined increased in normal adrenals, while aldosterone production did not increase so much in hyperplastic adrenals of Cushing's syndrome as compared with other corticoids production.3. The production of aldosterone and corticosterone was stimulated by addition of synthetic angiotensin II to the incubation medium in normal adrenals, but only aldosterone production was promoted by angiotensin II in the adrenal of primary aldosteronism.

The absorption bands of colloidal zinc and mercury in KCl have been calculated.It is considered that the electronic transition bands of these neutral metals in KCl of Ben-Dor et al.had better been.assigned as colloidal origin.

The precision of the parabolic interpolation technique which have been usually applied for the computations bf the two-center transition moment integrals with Slater Orbitals of non-integer effective principal quantum numbers is ascertained tolerable by comparing with the results of the McLaurin series expansion technique.

Au-glass becomes black immediately after the irradiation. It becomes transparent after a subsequent heat treatment at 200°C, and becomes red after a subsequent heat treatment at above 500°C. These changes are attributed to the formation of F-centers, annihilation of F-centers, and formation of colloidal gold respectively. In unirradiated Au-glass, colloidal gold is formed after a heat treatment at above 800°C. In Mn-glass an absorption band is observed at 540 mµ after the irradiation. It is attributed to the change of the “substitutional” Mn+2 (substituted for Si+4) into Mn+3. On the other hand, the “interstitial” Mn2+ (substituted for Na+) prevents the formation of F-centers, presumably because of the strong interaction between the free electron and Mn+2, which is substituted for Na+. The lack of electrical neutrality of Mn2+ is suggested. It is shown from ESR experiments that the aggregation of Mn+2 does not occur in glass at room temperature. The experimental results about glasses containing other impurities are also briefly described.

The types of radicals formed in irradiated polyoxymethylene are suggested from electron-spin-resonance spectral measurements. (L.N.N.)