Modulatory effect of interleukin-1β on rat isolated basilar artery contraction

An increased level of cytokine interleukin-1 (IL-1) has been detected around the site of stroke. However, the effect of IL-1β on the basilar artery has received little attention. We evaluated the effects of IL-1β on the contractile response of rat isolated basilar artery by measuring isometric tension change. IL-1β (10 ng/ml) and phenylephrine (0.1 nM) markedly enhanced U46619 (30 and 100 nM)-induced basilar artery contraction. The IL-1β-mediated potentiation was partly suppressed by zinc protoporphyrin (3 μM) and was abolished by tetrodotoxin (TTX, 100 nM), (-)-perillic acid (1 μM), PD98059 (0.3 μM), SB203580 (1 μM) and prazosin (1 μM). Our data suggest that IL-1β (10 ng/ml) causes an enhancement of U46619-mediated basilar artery contraction that probably involves TTX-sensitive neuronal release of an α₁-adrenoceptor agonist and activation of p42/p44 and p38 mitogen-activated protein kinases/p21^ras pathways.