Cytokines increase endothelin ETB receptor contractile activity in rat cerebral artery

THE plasticity of endothelin ETB receptor activity and the influence of pro -inflammatory cytokines was examined in cerebral artery. In fresh rat basil ar artery, the selective ETB receptor agonist, sarafotoxin S6c, induced neg ligible contractions. However, after 1 day of organ culture, fully defined concentration-response curves were obtained in artery segments exposed to s arafotoxin S6c. Organ culture in the presence of either interleukin-1 beta or tumour necrosis factor-alpha, but not interleukin-2 or interleukin-6, fu rther amplified the maximal contraction to sarafotoxin S6c. The plasticity of ETB recpetor expression in cerebral arteries and sensitivity for pro-inf lammatory cytokines, suggest a role in inflammatory cerebral diseases such as stroke. NeuroReport 10:2355-2359 (C) 1999 Lippincott Williams & Wilkins.