EVIDENCE FOR THE INVOLVEMENT OF THE CRUSTACEAN HYPERGLYCEMIC HORMONE IN THE REGULATION OF LIPID-METABOLISM

Effects of the crustacean hyperglycemic hormone on total lipids in the hemolymph of Chasmagnathus granulata and on free fatty acids, phospho lipids, and triglycerides in the hemolymph of Carcinus maenas, as well as on their release by Orconectes limosus hepatopancreas in vitro, we re investigated. Eyestalk ablation led to a significant decrease of to tal lipids in the hemolymph of C. granulata and of free fatty acid lev els in C. maenas. Crustacean hyperglycemic hormone injections complete ly reversed the effects of eyestalk extirpation in short-term experime nts. Crustacean hyperglycemic hormone also caused significant elevatio ns of hemolymph phospholipids and triglycerides in eyestalkless C. mae nas. The release of free fatty acids and phospholipids from O. limosus hepatopancreas in vitro was significantly increased in the presence o f crustacean hyperglycemic hormone. These results suggest a physiologi cal role for crustacean hyperglycemic hormone in the control of lipid metabolism in crustaceans. This role may be similar to that of the adi pokinetic hormone of insects.