title: Effect of hog anaphylatoxin (C 5a) on vascular permeability and leukocyte emigration in vivo.
abstract: The effects of highly purified hog anaphylatoxin (C 5a) on leukocyte emigration were investigated in guinea pigs in vivo using two experimental models: 1. Subcutaneous infusions. Sterile solutions of C 5a in saline infused at a rate of 1.8 mug C 5a/h (0.2 ml/h) for 10 h induced a dense accumulation of leukocytes, mainly neutrophils but also some eosinophils at the site of application; In control infusions with saline alone comparatively few leukocytes were found. 2. Single injections into the pleural cavity. 10 or 20 mug C 5a (dissolved in 2 ml saline) caused a dose-dependent increase in leukocyte number and volume of pleural exudate. Bradykinin in a dose of 18 mug produced similar fluid exudation as 20 mug C 5a but had no significant effect on leukocyte accumulation. Intrapleural injections of C 5a further caused the appearance of i.v. injected Evans blue in the pleural cavity. This effect, indicating an increase in vascular permeability lasted for about 3 h; Since at least one of the two models used - subcutaneous infusion -simulates natural conditions -continuous local generation of C 5a in small amounts at the site of an inflammatory lesion-the results indicate that C 5a once formed by complement activation in natural defense reactions may contribute to local increase in vascular permeability and leukocyte infiltration.
mesh_terms: D000706:Anaphylatoxins / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D002199:Capillary Permeability / Q000187:drug effects*; D002634:Chemotaxis, Leukocyte / Q000187:drug effects*; D006168:Guinea Pigs; D007267:Injections; D007279:Injections, Subcutaneous; D010455:Peptides / Q000494:pharmacology*; D010994:Pleura / Q000166:cytology / Q000187:drug effects; D012867:Skin / Q000166:cytology / Q000187:drug effects
chemical_list: D000706:Anaphylatoxins; D010455:Peptides