Inhibition of Endothelin (ET-1) Induced Pressor Responses by the Endothelin (ETA) Receptor Antagonist FR139317 in the Pithed Rat

Publisher Website
Google Scholar
Abstract
The effects of the novel ETA receptor antagonist, FR 139317, on ET-1 induced blood pressure changes were studied in the pithed Sprague-Dawley rat. FR139317 in a dose of 0.025 mg/kg b.w. had no effect while 0.05-1 mg/kg b.w. dose dependently inhibited the pressor response to an i.v. bolus injection of ET6-1 (800 pmoles/kg). While FR139317 potently inhibited the magnitide and duration of the ET-1 induced pressor response, the ETA antagonist did not significantly influence the shortlasting initial depressor response. We conclude that FR139317 in the pithed rat potently inhibits ET-1 mediated pressor responses and that this agent may become a significant tool to elucidate the putative physiological and pathophysiological role of ETA receptor mediated responses.