Abstract
1. Atrial natriuretic peptide (ANP) (10(-9) to 10(-8) M) produced a concentration-related relaxation in helical strips of dog cerebral arteries partially contracted with prostaglandin F2 alpha. The relaxation was not affected by treatment with ouabain, quinidine, oxyhaemoglobin, methylene blue, or removal of endothelium. 2. Relaxations induced by nicotine or transmural electrical stimulation were not reduced in arteries in which tachyphylaxis to ANP had developed. 3. In arteries exposed to Ca2+-free media under severe hypoxia, contractions due to prostaglandin F2 alpha and Ca2+ were attenuated by treatment with ANP, whereas the reoxygenation-induced contraction was unaffected. 4. The results suggest that ANP does not mediate neurogenic relaxation of dog cerebral arteries. The ANP-induced relaxation is not associated with activation of the sodium pump but is due to an inhibitory action on the release and influx of Ca2+, probably as a result of stimulation of guanylate cyclase.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
