Abstract
Summary
1. A study was made of the effects of a single injection of anterior pituitary purified growth hormone on distribution of lipides and turnover of phospholipides in plasma, liver and aorta a few hours after administration in intact rabbits. 2. Plasma glucose and liver glycogen concentration, and total liver weight were moderately, but significantly, increased in animals which received growth hormone. 3. Contents of all lipide fractions of plasma and entire liver were significantly increased in experimental animals. In the aorta, the only change was a significantly decreased neutral fat content. 4. Liver total lipide content was increased 64%, plasma total lipide was increased 85%, and aorta total lipide was decreased 25%. The relative contribution of each lipide fraction to percentage increased or decreased total lipide determined in these tissues was as follows: in liver, neutral fat contributed 47%, phospholipide 15%, and free and ester cholesterol 1.5% each; in plasma, neutral fat contributed 53%, phospholipide 19%, free cholesterol 6%, and esterified cholesterol 8%; in the aorta, neutral fat contributed 100%. 5. Radioactivity data showed that accelerated synthesis of liver and plasma phospholipides occurred after treatment with growth hormone; but aortic phospholipide turnover was not different from controls. 6. It is suggested that increased rate of formation of phospholipides of liver and plasma need not necessarily be a specific effect of growth hormone but a change in this parameter of metabolism subsidiary to enhanced mobilization of endogenous fat. It is further suggested that all elements of altered distribution of lipides in tissues analyzed could be explained in accordance with the concept of a primary adipo-kinetic action of growth hormone.
Get full access to this article
View all access options for this article.