MICROTUBULE DISRUPTION POTENTIATES PHENYLEPHRINE-INDUCED VASOCONSTRICTION IN RAT MESENTERIC ARTERIAL BED

The presser response induced by phenylephrine in the rat isolated mese nteric arterial bed was significantly increased following treatment wi th nocodazole, a drug that disassembles microtubules (10 mu M, 90 min) . This increase was even greater in the presence of nitric oxide (NO) synthase inhibition, and completely reversed by paclitaxel (20 mu M), a stabilizer of microtubules. These results demonstrate that disassemb ly of microtubules enhances vasoconstriction to receptor activation, s uggesting that the microtubules modulate the transduction of intracell ular signals in endothelium and vascular smooth muscle cells. (C) 1998 Elsevier Science B.V. All rights reserved.