Cod CGRP and tachykinins in coeliac artery innervation of the Atlantic cod, Gadus morhua: presence and vasoactivity.
The presence and vasoactive effects of native calcitonin gene-related peptide (CGRP), substance P (SP), and neurokinin A (NKA) were studied on isolated small branches of the coeliac artery from Atlantic cod, Gadus morhua, using immunohistochemistry and myograph recordings, respectively. Immunohistochemistry revealed nerve fibers containing CGRP- and SP/NKA-like material running along the wall of the arteries. CGRP induced vasorelaxation of precontracted arteries with a pD(2) value of 8.54 +/- 0.17. Relaxation to CGRP (10(-8) M) was unaffected by L-NAME (3 x 10(-4) M) and indomethacin (10(-6) M) suggesting no involvement of nitric oxide or prostaglandins in the CGRP-induced relaxation. SP and NKA (from 10(-10) to 3 x 10(-7) M) contracted the unstimulated arteries at concentrations from 10(-8) M and above in 42% and 33%, respectively, of the vessels. It is concluded that the innervation of the cod celiac artery includes nerves expressing CGRP-like and tachykinin-like material, and that a vasodilatory response to CGRP is highly conserved amongst vertebrates while the response to tachykinins is more variable.
Shahbazi
Fatemeh
F
Department of Zoophysiology, Göteborg University, P.O. Box 463, 405 30, Goteborg, Sweden. fatemehs2003@yahoo.com
Holmgren
Susanne
S
Jensen
Jörgen
J
D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism / Q000494:pharmacology*; D002445:Celiac Artery / Q000187:drug effects* / Q000294:innervation* / Q000378:metabolism; D004576:Electromyography; D048389:Gadus morhua / Q000502:physiology*; D007150:Immunohistochemistry; D015288:Neurokinin A / Q000378:metabolism / Q000494:pharmacology*; D013373:Substance P / Q000378:metabolism / Q000494:pharmacology*; D014664:Vasodilation / Q000187:drug effects*
D013373:Substance P; D015288:Neurokinin A; D015740:Calcitonin Gene-Related Peptide