title: Changes in sympathetic and endothelium-mediated responses in the rabbit central ear artery after acrylamide treatment.
abstract: The effect of acrylamide intoxication on the innervation and local control of the rabbit central ear artery was investigated. There was no difference in the noradrenaline, neuropeptide Y and calcitonin gene-related peptide tissue content between control and experimental animals. There was, however, a slight reduction in catecholamine histofluorescence. Although the contractile efficiency of the rabbit central ear artery as measured by responses to potassium chloride was unchanged, nerve-mediated contractile responses were significantly attenuated in acrylamide-treated animals. Contractile responses induced by exogenous alpha,beta-methylene ATP were markedly increased after acrylamide treatment, in contrast to contractions induced by exogenous noradrenaline which were attenuated at maximal concentrations. Modulatory effects of nerve-mediated contractile responses by neuropeptide Y were unaffected by acrylamide intoxication. It therefore appears that acrylamide intoxication damages sympathetic cotransmission, perhaps with preferential action on the purinergic component. Endothelium-dependent relaxant responses to acetylcholine and substance P were attenuated in acrylamide-treated animals, whereas relaxant responses mediated by calcitonin gene-related peptide (endothelium independent) were unaffected. The question of whether the damage to the endothelial cell action is a primary effect, or a secondary consequence of sympathetic nerve damage, is discussed.
authors.affiliation: Department of Anatomy and Developmental Biology, University College London, U.K.
authors.forename: K I
authors.initials: KI
authors.lastname: Maynard
authors.forename: J
authors.initials: J
authors.lastname: Lincoln
authors.forename: P
authors.initials: P
authors.lastname: Milner
authors.forename: G
authors.initials: G
authors.lastname: Burnstock
mesh_terms: D020106:Acrylamide; D000178:Acrylamides / Q000494:pharmacology*; D000255:Adenosine Triphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D000818:Animals; D001158:Arteries / Q000187:drug effects; D004423:Ear / Q000098:blood supply*; D004730:Endothelium, Vascular / Q000502:physiology*; D008297:Male; D009478:Neuropeptide Y / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology; D011817:Rabbits; D013564:Sympathetic Nervous System / Q000502:physiology*; D014661:Vasoconstriction; D014664:Vasodilation / Q000502:physiology
chemical_list: D000178:Acrylamides; D009478:Neuropeptide Y; D020106:Acrylamide; D000255:Adenosine Triphosphate; C002630:alpha,beta-methyleneadenosine 5'-triphosphate; D009638:Norepinephrine