5-Hydroxytryptamine does not reduce sympathetic nerve activity or neuroeffector function in the splanchnic circulation.

摘要: Abstract Infusion of 5-hydroxytryptamine (5-HT) in conscious rats results a sustained (up to 30 days) fall blood pressure. This is accompanied by an increase splanchnic flow. Because the circulation regulated sympathetic nervous system, we hypothesized that 5-HT would: 1) directly reduce nerve activity region; and/or 2) inhibit neuroeffector function vessels. Moreover, removal innervation (celiac ganglionectomy) would 5-HT-induced hypotension. In anaesthetized Sprague-Dawley rats, mean pressure was reduced from 101±4 63±3 mm Hg during slow infusion (25 μg/kg/min, i.v.). Pre- and postganglionic were unaffected infusion. superior mesenteric arterial rings prepared for electrical field stimulation, neither (3, 10, 30 nM), 5-HT1B receptor agonist CP 93129 nor 5-HT1/7 5-carboxamidotryptamine inhibited neurogenic contraction compared vehicle. did not venous rings. Finally, celiac ganglionectomy modify magnitude or time course hypotension when animals receiving sham ganglionectomy. We conclude it unlikely interacts with system at level preganglionic nerve, as well junction, These important studies allow us rule out direct interaction cause