The inhibition of lipid synthesis in vitro in the locust, Schistocerca gregaria, by factors from the corpora cardiaca

Abstract

ABSTRACT. The rate of lipid synthesis from [ 14 C]acetate in fat body from Schistocerca americana gregaria has been studied in vitro. Maximum incorporation is found on days 6–10 in adults and day 4 of the fifth stadium. The label appeared in the fatty acid components of triacyl‐glycerol, diacylglycerol and phospholipid. Lipid synthesis in vitro was inhibited by extracts of corpora cardiaca, and such inhibition was most marked (up to 85%) in fat bodies from insects at stages where fatty acid synthesis was greatest. HPLC separation of corpora cardiaca extracts gave several active fractions of which the most active was adipokinetic hormone 1 (AKH‐1).