Aim: 

Cardiovascular events during anaphylaxis may result in life dangerous state – circulatory shock. The role of endothelium in different vascular beds during this pathological state remains to be elucidated. The purpose of this study was to assess the possible implication of vascular endothelium into vascular events during anaphylaxis.

Methods: 

Guinea pigs were actively sensitized using horse serum. For investigation we used small mesenteric and coronary arteries (350-450 mm in diameter) from sensitized and sham sensitized guinea pigs. Anaphylaxis of blood vessels was performed in vitro adding 1% of horse serum to the organ bath. Vascular effects of anaphylaxis were quantified using small blood vessels wire myography method.

Results: 

Antigen challenge resulted in anaphylactic contraction in both mesenteric (3.69 ± 1.72 mN) and coronary (3.45 ± 1.02 mN) arteries. This contractile response remained after the removal of endothelium, but it was decreased till 56.3 ± 11.8% (p < 0.05) in coronary vessels and till 90.8 ± 8.6% (p > 0.05) in mesenteric vessels. The inhibition of nitric oxide synthase using L-NAME decreased the anaphylactic contraction in mesenteric arteries (till 64.2 ± 20.8%; p > 0.05), but increased in coronary arteries (till 187.8 ± 32.3%; p < 0.05).

Conclusion: 

The endothelial factors play modulating role in anaphylaxis of small isolated coronary and mesenteric arteries in guinea pig, acting against anaphylactic contraction.