The growth rates, various organ weights and plasma and liver cholesterol levels were examined in rats fed diets containing various levels of PCB (Aroclor-1248) or p, p'-DDT. The effect of concurrent addition of konjac mannan, pectin, carboxymethyl cellulose, anion exchange resin (AG 2-X8, C1 form) or sodium cholate on these indices was also studied.
1. The growth rate in rats fed 0.2% PCB diet was about one-half that of the normal group. Any growth retardation did not occur when dietary PCB level was below 0.02%, but the animals died within 3-4 days when a 1% PCB diet was given.
2. Liver weight in rats received PCB was significantly increased in proportion to the dietary PCB level.
3. Spleen weight was decreased in PCB fed groups. There was little or no effect on the weight of heart, kidney and adrenal.
4. Plasma and liver cholesterol concentrations were significantly increased when fed PCB containing diets, being 1.5-2.2 times higher than that of the normal group with a distinct dose-response. The response in plasma cholesterol level was rapid and a significant difference was obtained only 2 days following the PCB feeding.
5. Concurrent addition of konjac mannan or pectin depressed the elevation in plasma cholesterol due to PCB intake, but could not improve hypertrophy or elevated cholesterol levels in the liver.
6. Concurrent addition of anion exchange resin did not depress the plasma cholesterol level.
7. Plasma triglyceride level which was significantly increased in rats fed a 0.2% PCB diet was depressed when 3% konjac mannan or pectin was concurrently supplemented to this diet.
The similar experiments were carried out at the dietary levels of 0.002, 0.02 or 0.2% p, p'-DDT, respectively.
8. Plasma cholesterol level was significantly increased in rats fed 0.2% DDT and did not increase at the lower DDT levels.
9. Concurrent addition of konjac mannan to the diet containining 0.02% DDT caused a significantly low plasma cholesterol level as compared with the value in rats fed 0.02% DDT diet. However, this depression was equivocal in another experiment.
10. 0.2% DDT level caused whole body convulsion, but the animals continued to grow although at a slower rate.

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In a previous paper we reported that the diet containing 1.5% of soy sterols and of unsaponifiable matter separated from soybean oil markedly prevented the increase in plasma cholesterol caused by ingestion of cholesterol. It was presumed that the synergistic effect of the unsaponifiable matter was due to tocopherols present in it.
The purpose of the present paper was to know the effectiveness of tocopherols on plasma cholesterol levels. Rats were given cholesterol and soy sterols with or without tocopherols. After a 30-day feeding period it was recognized that plasma cholesterol fed tocopherols was greatly reduced.
To elucidate the reducing mechanism of plasma cholesterol by tocopherols, sterols excreted into feces were determined. It was noted that there was an increased fecal excretion of cholesterol, while soy sterols in feces were decreased, that is, the absorption of soy sterols was increased. Moreover, we noticed the presence of a large amount of stigmasteral and β-sitosterol in both plasma and liver sterols. It is known that β-sitosterol and stigmasterol are more effective in lowering plasma cholesterol values, compared to ergosterol and campesterol, however, it is also known that the absorption coefficient of β-sitosterol is quite low (less than 5%).
The results indicate that the plasma cholesterol reducing effect of tocopherols is presumably by the increasing absorption of β-sitosterol and stigmasterol and thus absorbed vegetable sterols show hypocholesterolemic effects in rats.

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Effect of the levels of dietary protein on the concentration of lipids and lecithin: cholesterol acyltransferase (LCAT) activity in rat plasma was examined.
Male rats were fed the cholesterol-free diets containing three different levels of casein (8, 20 and 32%) for 16 days, or for 2 days after 2 day fasting. By increasing the dietary protein levels, the concentration of cholesterol was increased and this was much remarkable in the esterified form than in the free ones. The plasma phospholipid concentration also appeared to increase. The content of arachidonic acid in cholesterol esters was increased by increasing dietary protein. Though LCAT activity was not influenced by the differences in the dietary regimens, in vitro formation of cholesterol arachidonate by this enzymatic reaction was enhanced when the protein level in diets was increased.

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The effects of cold expusure (5°C) on feed intake, growth rate, plasma FFA, liver and abdominal muscle fat oxidation etc. were studied.
The 5°C groups of rats intaked more of all diets than 20°C groups. The growth rate and F. E. R. (feed efficiency ratio) at 20°C were greater than 5°C. The plasma phospholipid levels, liver and abdaminal muscle fat oxidation leveis rose in rats maintained at 5°C.
The oxidation of fat was closely related with dietary protein levels.

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Thirteen kinds of commercial household margarine and two kinds of butter were preserved for 12 months at 5° and 20°C, and the change in flavor and the development of odor were examined at one-month intervals, together with the vitamin A and β-carotene contents.
None of the samples preserved at 5°C developed any odor during the whole period of preservation but some preserved at 20°C envolved abnormal odor.
Average of vitamin A remained at 3, 6 and 12 months was 99.1, 97.5 and 91.6%, respectively, when preserved at 5°C but was 97.0, 93.3 and 83.0%, respectively, when preserved at 20°C. Decrease in the amount of β-carotene was slightly lower than that of vitamin A. There was hardly any difference in these values between samples in a cup and in carton package.
Samples with higher content of linoleic and linlenic acids showed greater increase of P. O. V., whose values showed correlation of the amount of remaining vitamin A and β-carotene.
There was no remarkable effect of the addition of antioxidant or dehydroacetic acid. Preservation at low temperature seemed to have the best effect on the stabilization of the quality.

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Tetrasodium monoferrous dicitrate (abbreviated to FC) was easily dissolved and remained stable in water at wide pH range, as a low molecular chelate. Although 80% of ferrous iron was oxidized to ferric form in neutral medium, it remained absorbable by the intestine.
The rates of intestinal absorption and utilization of this compound were compared with those of ferrous sulfate by per oral administration to anemic rats. The compounds (0.3mg Fe/rat in each time) were administered by ten times doses during ll days and the recovery of Hb value was assayed at every three days interval and accumulation of nonhemin iron in liver and spleen was determined after 48 hours of the last administration. ⁵⁹Fe labeled compounds were administered with the first dose to determine the rate of the intestinal absorption. The rate of intestinal absorption of ⁵⁹Fe was anemia dependent and significantly increased from 5% in normal rats to 70% in severe anemic rats, and it was also clearly shown that the incorporation of iron into hemoglobin had preference to the accumulation of nonhemin iron in liver in both compounds.
The utilization of FC for anemic rats was recognized closely to correspond with that of ferrous sulfate except that the recovery of Hb value tended to be more rapid in the midway and the accumulation of nonhemin iron in liver was smaller than the animals administered ferrous sulfate.

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The effective period of adrenal corticoid administration for the maintenance of pregnancy in proteideprived rats was investigated. A quarter mg of hydrocortisone was injected daily subcutaneously into the rats receiving a protein-free diet for various periods. Rats receiving steroid between days 4-7, 4-9, 4-11 and 4-13 maintained pregnancy in 20%, 62%, 38% and 27% of the animals, respectively. In these animals pregnancy was maintained with decrease in maternal body weight. Hydrocortisone did not show the adverse effect on maintenance of pregnancy in rats fed a normal diet. There were no differences in growth of conception products on day 14 between the groups with and without feeding protein, while total RNA and DNA in the uterus of protein fed group were higher than those in protein-deficient group.
Mechanisms involved in maintenance of hydrocortisone induced pregnancy are briefly discussed.

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In order to elucidate the mechanism of plasma cholesterol reducing action by Shiitake mushroom (Lentinus edodes) or eritadenine (plasma cholesterol lowing substance in Shiitake), the levels of lipidsin plasma and liver, and the composition of plasma lipoproteins were studied in rats.
Plasma lipids and plasma lipoprotein levels were decreased by feeding of Shiitake and eritadenine, although, liver lipids levels were increased. In particular, α-lipopratein in plasma was decreased by eritadenine. The results suggest that the reduction of plasma cholesterol level by eritadenine may due to the decrease of plasma α-lipoprotein.

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The effect of vitamin B₆ deficiency was observed on the plasma free amino acid pattern of the rats fed with various levels of protein.
For this purpose the body weight, food intake, liver threonine dehydratase and plasma free amino acid contents were determined for rats fed with 6%, 18% or 70% casein and with or without vitamin B₆ intake. The body weight increase (the initial body weight: 70g) was the lowest in the 6% casein group of the control, while the body weight decrease due to vitamin B₆ deficiency was the most marked in the 70% casein group and the least in the 6% casein group. The threonine dehydratase activity was higher when the protein intake was higher, and the decrease of the activity due to vitamin B₆ deficiency was also higher when the protein intake was higher. The concentrations of the plasma free amino acids were higher as the protein intake level increased among the control groups, while they were lower among the deficiency groups. The higher concentration was observed for threonine, glycine and methionine in the deficiency groups compared with the control groups, while the lower values were observed for most other amino acids.

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Composition of fatty acid and sterol constituents in the principal neutral lipid classes of rice grain, namely triglyceride, diglyceride, free fatty acid, sterolester and free sterol, was investigated. The individual lipid class was isolated from the neutral lipid fraction by preparative thin-layer silicic acid chromatography, brought to methanolysis and analyzed for the component fatty acid and sterol by gas-liquid chromatography.
The main fatty acids in triglyceride, diglyceride and free fatty acid were commonly oleic, linoleic and palmitic acid in decreasing order. The major fatty acids in sterolester fraction were linoleic, oleic and palmitic acid in decreasing order.
The chief sterols in sterolester and free sterol were β-sitosterol, campesterol and stigmasterol, among which β-sitosterol was dominating.

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