Lipid metabolism in the cockroach, Periplaneta americana, is activated by the hypertrehalosemic peptide, HTH-I.
Phosphatidylcholine and phosphatidylethanolamine are the major constituents of the phospholipid pool in cockroach (Periplaneta americana) fat body and hemolymph. Both species of phospholipid are significantly decreased 6h after injecting hypertrehalosemic hormone I (HTH-I) into the hemocoel. Loss of phospholipid is accompanied by an accumulation of the phospholipid degradation products glycerophosphorylcholine and glycerol. HTH-I also increases phospholipase activity in the hemolymph and this is thought to be responsible for the depletion of hemolymph phospholipid. Phospholipase activity peaks approximately 2h after injection of HTH-I and returns to normal at 6h. In vitro, total phospholipid in the fat body is decreased by HTH-I whereas the concentration of diacylglycerol displays a corresponding increase. HTH-I elevates free fatty acid levels but has no effect on triacylglycerol. These effects of HTH-I are blocked by the phospholipase inhibitor mepacrine.
Oguri
Elisha
E
Department of Biology, The University of Western Ontario, Ont., N6A 5B7, London, Canada.
Steele
John E
JE
D000818:Animals; D004789:Enzyme Activation / Q000187:drug effects; D005216:Fat Body / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D006458:Hemolymph / Q000737:chemistry / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D050356:Lipid Metabolism; D008297:Male; D009479:Neuropeptides / Q000494:pharmacology*; D010526:Periplaneta / Q000187:drug effects* / Q000378:metabolism*; D010740:Phospholipases / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism; D011796:Quinacrine / Q000494:pharmacology
D009479:Neuropeptides; D010743:Phospholipids; C043192:glutamyl-valyl-asparaginyl-phenylalanyl-seryl-prolyl-asparaginyl-tryptophanamide; D010740:Phospholipases; D011796:Quinacrine