Altered endothelium-mediated relaxation by sympathectomy in isolated rabbit carotid artery rings.
The influence of cervical and periarterial sympathectomy on endothelium-dependent and endothelium-independent relaxations of the mature rabbit carotid artery was studied in vitro. The responses to adenosine, vasoactive intestinal polypeptide and substance P in sympathectomized and control rabbit carotid artery rings were recorded and analyzed. The effects of endothelium removal were also investigated. The maximal relaxation achieved by substance P, which produces endothelium-dependent relaxation, was significantly inhibited in 3 weeks in postsympathectomy arterial preparations as compared to controls. Adenosine and vasoactive intestinal polypeptide, which produce endothelium-independent relaxation, elicited similar relaxation in all tissues. These results demonstrated that the response to substance P was impaired by cervical and periarterial sympathectomy. The decreased maximum response to substance P may be the result of a decreased NK-1 receptor subtype density or excitation/response coupling, or it may be due to an impaired production and/or liberation of endothelium-derived relaxing factor (EDRF).
Kaya
T
T
Department of Pharmacology, Faculty of Medicine, Cumhuriyet University, Sivas, Turkey.
Utkan
T
T
Sarioglu
Y
Y
Göksel
M
M
D000241:Adenosine / Q000494:pharmacology*; D000818:Animals; D002339:Carotid Arteries / Q000187:drug effects / Q000502:physiology*; D004730:Endothelium, Vascular / Q000502:physiology*; D005260:Female; D066298:In Vitro Techniques; D008297:Male; D009126:Muscle Relaxation / Q000502:physiology; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000502:physiology*; D009569:Nitric Oxide / Q000378:metabolism; D011817:Rabbits; D018040:Receptors, Neurokinin-1 / Q000187:drug effects / Q000378:metabolism; D013373:Substance P / Q000494:pharmacology; D013562:Sympathectomy; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology*; D014665:Vasodilator Agents / Q000494:pharmacology*
D018040:Receptors, Neurokinin-1; D014665:Vasodilator Agents; D009569:Nitric Oxide; D013373:Substance P; D014660:Vasoactive Intestinal Peptide; D000241:Adenosine