The role of mast cells and histamine in leukocyte-endothelium interactions in four rat strains.
The objective of the present study was to determine the role of mast cells and histamine in leukocyte-endothelium interactions in mesenteric venules of four rat strains: Brown Norway, Lewis, Sprague-Dawley and Wistar. Intravital microscopy showed that the mast cell stabilizer cromoglycate (5 mg/kg i.v. just before exteriorization of the mesentery) did not affect the baseline level and velocity of leukocyte rolling in any of the four strains. This finding is in agreement with the observation that cromoglycate pretreatment only slightly influenced mast cell degranulation in all strains except the Brown Norway. After mast cell stabilization, only in Sprague-Dawley did topical administration of histamine (10(-4) M) result in a significant increase in the level of leukocyte rolling and a decrease in the rolling velocity compared with the time control. Histamine induced leukocyte adhesion only in the Brown Norway strain. In conclusion, the hypothesis presented in other studies, that degranulation of mast cells, and more specifically the release of histamine, is of major importance for the induction of leukocyte-endothelium interactions in rat mesenteric venules is not generally applicable; the present study shows a clear strain dependency.
Tromp
S C
SC
Department of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, P.O. Box 616, NL-6200 MD, Maastricht, The Netherlands.
Tangelder
G J
GJ
Slaaf
D W
DW
Reneman
R S
RS
van Velzen
S
S
Engels
W
W
van Breda
E
E
oude Egbrink
M G
MG
D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D004205:Cromolyn Sodium / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000502:physiology*; D006632:Histamine / Q000494:pharmacology / Q000502:physiology*; D007958:Leukocyte Count; D007962:Leukocytes / Q000187:drug effects / Q000502:physiology*; D008407:Mast Cells / Q000502:physiology*; D008642:Mesenteric Veins / Q000166:cytology; D051381:Rats; D011914:Rats, Inbred BN; D011917:Rats, Inbred Lew; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D013045:Species Specificity
D006632:Histamine; D004205:Cromolyn Sodium