Abstract
Kågström, J. and S. Holmgren. Calcitonin gene-related peptide (CGRP), but not tachykinins, causes relaxation of small arteries from the rainbow trout gut. Peptides 19(3) 577–584, 1998.—Possible vasoactive effects on small diameter arteries from the rainbow trout gut of calcitonin gene-related peptide (CGRP-chicken) and different fish tachykinins; substance P (SP-trout), neurokinin A (NKA-trout), scyliorhinin I and II (SCY I and SCY II-dogfish), were investigated. CGRP relaxed precontracted arteries with a pD 2 value of 8.3 ± 0.2. Relaxation to CGRP 10 −8 M was reduced by 86.4 ± 5.2% by the CGRP-1 receptor antagonist CGRP 8–37 (10 −6 M), but unaffected by N G-nitro- l-arginine (10 −4 M), indomethacin (10 −6 M) and by removal of the endothelium, suggesting no involvement of nitric oxide, prostaglandins or endothelium-derived factors. A low number of CGRP immunoreactive fibers were present in the arterial wall. The tachykinins (10 −12–10 −6 M) occasionally contracted the relaxed vessel. No synergistic action of SP on the CGRP-induced response was found. A dense plexus of tachykinin-containing fibers without coexisting CGRP innervated the arterial wall. Tachykinins or CGRP had no effect on small diameter veins, and no such immunoreactivity was found in these vessels. In conclusion, CGRP- and tachykinin-containing fibers innervate trout gut arteries. CGRP probably is vasodilatory, while the function of the tachykinin fibers is unknown.
Published Version
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.
