Lack of a direct correlation between cholesterol synthesis and cell renewal in liver and intestine in the rat.

An attempt was made to investigate whether the synthesis of cholesterol is correlated with the synthesis of DNA in the rat. This study was carried out in vivo on two organs in which the cell renewal is known to be different: the liver and the intestine. Various experimental conditions were realized which modify the rate of cholesterol synthesis in these organs. Measurements of the incorporation of [14C] acetate into the unsaponifiable lipids and of [3H] thymidine into the nuclear DNA give respectively an index for the intensity of cholesterol- and DNA syntheses. Radio activities were measured 70 min after subcutaneous injection of the two labelled precursors. The results showed that the intensity of cholesterol synthesis in the intestine and in the liver can change without proportional variations of DNA synthesis in these organs. Thus, it is not possible to establish a simple and direct correlation between the two synthesis.