Bradykinin-related peptides in the venom of the solitary wasp Cyphononyx fulvognathus.

摘要: Abstract Bradykinin (BK) and its related peptides are widely distributed in venomous animals, including wasps. In fact, we have previously purified a novel BK-related peptide (BRP) named Cd -146 the threonine 6 -bradykinin (Thr -BK) from venom of solitary wasp Cyphononyx fulvognathus . Further survey this same extract allowed structural characterization two other BRPs, here as fulvonin cyphokinin. Biochemical performed showed that although high primary structure similarity observed with BK, these not good substrates for angiotensin I-converting enzyme (ACE) acting more likely inhibitors enzyme. pharmacological assays, only those structurally similar to namely cyphokinin Thr -BK, were able promote contraction guinea-pig ileum smooth muscle preparations, which was completely blocked by B 2 receptors antagonist HOE-140 way BK. Only shown potentiate BK-elicited contraction. Moreover, new cyphokinin, well Cd- 146 hyperalgesic effect rat paw pressure test after intraplantar injection. This be due action on BK receptors, since hyperalgesia induced both 1 receptor antagonist, while -BK reversed antagonist. data give support better understanding function targets kinin-related found several insect venoms.