Pharmacologic assessment of bovine ruminal and mesenteric vascular serotonin receptor populations
| Autor: | Miriam A Snider, David L. Harmon, James L. Klotz |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Festuca
Male 0301 basic medicine Agonist Ergot Alkaloids Serotonin medicine.medical_specialty medicine.drug_class Toxicology Mesenteric Vein Contractility 03 medical and health sciences Mesenteric Veins Internal medicine Endophytes Genetics medicine Animals Saphenous Vein Mesenteric arteries CP-93129 Chemistry Epichloe 0402 animal and dairy science 04 agricultural and veterinary sciences General Medicine 040201 dairy & animal science Mesenteric Arteries Vasodilation 030104 developmental biology Endocrinology medicine.anatomical_structure Vasoconstriction Receptors Serotonin Cattle Animal Science and Zoology medicine.symptom LP-44 Food Science Blood vessel |
| Zdroj: | Journal of Animal Science. 96:1570-1578 |
| ISSN: | 1525-3163 0021-8812 |
| Popis: | Prior work using a contractility bioassay determined that the serotonin (5-HT) receptor subtype 5-HT(2A) is present in bovine lateral saphenous veins and plays a role in ergot alkaloid (EA)-induced vascular contraction in steers grazing endophyte-infected (Epichloë coenophiala) tall fescue (Lolium arundinaceum). Ergot alkaloids have also been shown to be vasoactive in bovine gut vasculature. To determine what 5-HT receptors are involved in vasoconstriction of gut vasculature, contractility of ruminal and mesenteric arteries and veins collected from cattle was evaluated in the presence of agonists selective for 5-HT(1B) (CP 93129), 5-HT(1D) (L-694, 247), 5-HT(2A) (TCB-2), 5-HT(2B) (BW 723C86), 5-HT(4) (BIMU-8), and 5-HT(7) (LP 44) receptors. Segments of ruminal and mesenteric veins and arteries were collected and suspended in a multimyograph containing continuously oxygenated Krebs–Henseleit buffer. Blood vessels were exposed to increasing concentrations of 5-HT agonists every 15 min and contractile response data were normalized as a percentage of the maximum contractile response induced by 120 mM KCl. Analysis of variance was evaluated using mixed models procedure of SAS for effects of agonist concentration for each vessel type. Receptor agonists for 5-HT(2B), 5-HT(1D), and 5-HT(7) did not induce a contractile response for ruminal or mesenteric vasculature (P > 0.05). However, when exposed to agonists for 5-HT(2B) or 5-HT(1D), mesenteric veins relaxed below zero (P < 0.05). Exposure of all 4 blood vessel types to 5-HT(2A) agonist induced contractile responses (P < 0.05). The findings of this study indicate that 5-HT(1D) and 5-HT(2B) are present in mesenteric veins and may play a role in vasorelaxation. Further, 5-HT(2A) is present in ruminal and mesenteric vasculature, plays a role in vasoconstriction of these vessels, and could be influenced by EA exposure as has been demonstrated in peripheral blood vessels. |
| Databáze: | OpenAIRE |
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