Pharmacological actions of chemically-modified phospholipase A2 from the venom of Trimeresurus flavoviridis on the smooth muscle of the rat stomach fundus.
The pharmacological activities of Trimeresurus flavoviridis phospholipase A2 (PLA2) and their chemically-modified PLA2 were characterized by measuring the contraction of rat stomach fundus strips. The native PLA2 produced a contraction of rat fundus strips. The alpha-amino-modified enzyme induced an almost identical contraction of the fundus with that of the native enzyme, whereas His-modified and Lys-modified enzymes induced a markedly decreased contraction as compared with the native enzyme. These results demonstrate that lysine and histidine residues but not the alpha-amino group in the PLA2 molecule are essential for contractile activity of the stomach fundus.
Kamata
K
K
Department of Pharmacology, School of Pharmacy, Hoshi University, Tokyo, Japan.
Arai
Y
Y
Kasuya
Y
Y
Aoki
Y
Y
Samejima
Y
Y
D000818:Animals; D003435:Crotalid Venoms / Q000494:pharmacology*; D005748:Gastric Fundus; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects* / Q000502:physiology; D010741:Phospholipases A / Q000494:pharmacology*; D054467:Phospholipases A2; D051381:Rats; D011919:Rats, Inbred Strains; D013329:Structure-Activity Relationship
D003435:Crotalid Venoms; D010741:Phospholipases A; D054467:Phospholipases A2