Application of high-performance liquid chromatography to the study of esterified 7-dehydrocholesterol in rat skin.

A novel and precise method for determining free and esterified 7-dehydrocholesterol in rat skin was developed by using a two-step high-performance liquid chromatography system. This method involves initial lipid extraction, separation of the free and esterified 7-dehydrocholesterol by, firstly, preparative high-performance liquid chromatography, saponification, and determination by, secondly, analytical high-performance liquid chromatography. This method was applied to the study of the 7-dehydrocholesterol in rat skin.

[Placental transfer and distribution of betamethasone 17,21-dipropionate in various regions of the brain of pregnant rats and mice (author's transl)].

As betamethasone 17,21-dipropionate induces adrenal atrophy in rat dams and adrenal hypertrophy in the fetus, we investigated the placental transfer of this compound using autoradiography and liquid scintillation counting in animals in the late stages of pregnancy. In these two species, 3H-betamethasone 17,21-dipropionate and/or its metabolites transferred across the placental barrier into fetal tissues and were distributed at levels lower than detected in the maternal tissues. The rat fetus showed a high uptake of radioactivity in the adrenal cortex.

Serum and lymph lipids in rabbits with carbon tetrachloride-induced cirrhosis of the liver.

Lymph flow and the composition of lymph lipids from the hepatic and thoracic ducts of rabbits with cirrhosis of the liver (induced by 46-51 intramuscular injections of a mixture of carbon tetrachloride and olive oil at 4-day intervals) have been compared with those of control animals injected with olive oil only. In cirrhotic animals, the concentration of lymph lipids was not greatly altered, but lymph flow, and consequently the hourly transport of lipids by lymph were greatly increased; the increase in transport of cholesteryl esters, free cholesterol, and phospholipids by way of the thoracic and hepatic duct lymph was particularly striking. The concentration of these lipid fractions in serum from the cirrhotic rabbits was also increased.