Anti-inflammatory property of 401 (MCD-peptide), a peptide from the venom of the bee Apis mellifera (L.).

1 Peptide 401, a potent mast cell degranulating factor from bee venom, substantially inhibited the oedema provoked by subplantar injection of carrageenin or intra-articular injection of turpentine in the rat. The ED(50) of 401 was c. 0.1 mg/kg. The anti-inflammatory effect was assessed by measurement of the increased (125)I-albumin content of an injected site in comparison with an uninjected contralateral site.2 Peptide 401 also suppressed the increased vascular permeability due to intradermal injection of various smooth muscle spasmogens (histamine, bradykinin, 5-hydroxytryptamine (5-HT), and prostaglandins).3 Other comparable mast cell degranulating agents (48/80 and melittin) showed little evidence of anti-inflammatory activity when tested at comparable dosage on turpentine arthritis and carrageenin oedema.4 The anti-inflammatory effects were not abolished by pretreatment with mepyramine and methysergide, which abolished the increased vascular permeability produced by local injection of 401.5 The anti-inflammatory action of 401 was not affected by regional denervation or pretreatment with phenoxybenzamine, and was reduced but not abolished by adrenalectomy.6 Measurement of skin temperature, fractional extraction of (86)Rb and blood flow in perfused mesentery gave no evidence that the anti-inflammatory action of 401 was due to reduced tissue perfusion.7 It is concluded that 401 may exert its anti-inflammatory action directly by making the vascular endothelium anergic to phlogistic stimuli.