system
Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Animals, Cats, Cerebral Arteries, Serotonin, Sympathetic Nervous System, Tryptophan Hydroxylase, Tyramine, Vasoconstriction.
user
Are cat cerebral arteries functionally innervated by serotoninergic fibers from central and peripheral origins? Context: Tryptophan hydroxylase activity and responses to tyramine were analyzed in cat cerebral arteries to investigate serotoninergic innervation. Enzymatic activity and responses to tyramine were measured in vessels from animals subjected to cervical gangliectomy and dorsal and median raphe nuclei lesions. Tryptophan hydroxylase activity in cat cerebral arteries was reduced after ganglia removal and raphe nuclei destruction. Contractile responses of the middle cerebral artery after gangliectomy were decreased by ketanserine. Dorsal raphe nucleus destruction had a significant effect on the contractile response, whereas median raphe nucleus destruction had only a slight effect.
assistant
Cat cerebral arteries receive serotoninergic innervation from central and peripheral origins. Final Decision: yes