EPIDERMAL GROWTH FACTOR-INDUCED RAPID RELAXATION OF THE ISOLATED RABBIT MESENTERIC-ARTERY

Epidermal growth factor (EGF) (10-100 ng ml(-1)) induced a rapidly dev eloping relaxation of precontracted rabbit mesenteric artery rings wit hin 30 min of exposure. Indomethacin or protein synthesis inhibitors p revented or acutely reversed the effect of EGF on the preparation and an erbstatin analogue significantly reduced it. It is concluded that t he EGF-mediated relaxation may be induced by the rapid production of p rostanoids via a cascade of biochemical events initiated by the tyrosi ne-kinase activity of the receptors for EGF. One or more proteins rapi dly produced and rapidly depleted appear to be involved in the activat ion of arachidonate metabolism.