Skin Sterols IV. Distribution of Δ 7 -Cholestenol. ∗

Abstract

Summary

1. The concentration of Δ₇-cholestenol in rat skin sterols increased rapidly from birth to 5-6 weeks of age but remained fairly constant thereafter. Skin sterols from adult male rats contained from 35-40% of Δ₇-cholestenol while skin from females contained 25-30%. These proportions did not change in severe pantothenic acid deficiency nor in hypothyroidism. Hyperthyroidism, however, appeared to increase the concentration of Δ₇-cholestenol in sterols from female rats. 2. The total fast-acting sterol in the skins of the wild rat and cotton rat were similar to those of the laboratory rat, while sterols from the skins of the mouse and guinea pig contained about 15% of a fast-acting component. The amounts of Δ₇-cholestenol were low in the skins of the pig, rabbit, dog, calf, chicken, and cat. A sample of human skin and a human atheromatous aorta contained negligible amounts of the new sterol.