The effect of Arvin on reticuloendothelial activity in rabbits.
1. Arvin stimulated the reticulo-endothelial uptake of colloidal carbon in rabbits. The onset of effect after intravenous administration was immediate and the minimum stimulant dose by this route was very low-0.05 unit/kg (0.1 mug protein/kg).2. Carbon opsonized in vitro with serum taken 4 h after an intravenous injection of Arvin was cleared more rapidly than carbon treated with control serum. Serum collected 10 min after Arvin did not promote carbon uptake.3. Reticulo-endothelial block with Thorotrast or excess carbon did not prevent the stimulant effect of Arvin but prevented the stimulant effect of opsonization with 4 h serum.4. The reticulo-endothelial stimulant effect of Arvin appears to be unrelated to its coagulant action on fibrinogen. The mechanism may involve a direct action on phagocytic cells and an effect on colloidal particles via serum opsonins.
D000818:Animals; D000925:Anticoagulants / Q000494:pharmacology*; D002244:Carbon / Q000378:metabolism; D003102:Colloids; D005340:Fibrinogen; D006023:Glycoproteins; D007106:Immune Sera / Q000494:pharmacology; D008297:Male; D012157:Mononuclear Phagocyte System / Q000187:drug effects* / Q000378:metabolism; D009895:Opsonin Proteins / Q000494:pharmacology; D010587:Phagocytosis; D011817:Rabbits; D012710:Serum Albumin, Bovine; D013268:Stimulation, Chemical; D013911:Thorium Dioxide; D014688:Venoms / Q000494:pharmacology*
D000925:Anticoagulants; D003102:Colloids; D006023:Glycoproteins; D007106:Immune Sera; D009895:Opsonin Proteins; D014688:Venoms; D012710:Serum Albumin, Bovine; D002244:Carbon; D005340:Fibrinogen; D013911:Thorium Dioxide