title: Cardiovascular effects of endothelin-1₁₋₃₁ microinjected into the nucleus tractus solitarius of anesthetized rats.
abstract: Endothelin-1₁₋₃₁ (ET-1₁₋₃₁) is a 31-amino-acid vasoactive peptide that plays an important role in the regulation of cardiovascular function. However, the cardiovascular effects of central ET-1₁₋₃₁ are still not fully understood. In this study, we assess the effects of ET-1₁₋₃₁ within the nucleus tractus solitarius (NTS) of anesthetized rats and explore the underlying mechanisms of these effects. Bilateral microinjections of ET-1₁₋₃₁ into the NTS produced dose-dependent hypotension and bradycardia, very similar to the effects of a unilateral microinjection of ET-1₁₋₃₁ into the NTS. Bilateral microinjections of ET-1₁₋₃₁ into the NTS significantly decreased baroreflex function in a time-dependent manner. The hypotensive and bradycardic effects induced by the microinjection of ET-1₁₋₃₁ into the NTS were significantly decreased by the ETA receptor antagonist BQ123 and by kynurenic acid, but not by the ETB receptor antagonist BQ788. These results show that ET-1₁₋₃₁ injected into the NTS produces hypotension and bradycardia, mediated by ETA receptors and, at least partly, by the glutamate receptor.
authors.affiliation: aDepartment of General Surgery, First Affiliated Hospital, Chongqing Medical University, Chongqing bDepartment of Emergency, Lanzhou University Second Hospital cDepartment of Clinical Laboratory, San Aitang Hospital, Lanzhou, China.
authors.forename: Peiwu
authors.initials: P
authors.lastname: Li
authors.forename: Xu
authors.initials: X
authors.lastname: Fu
authors.forename: Yan
authors.initials: Y
authors.lastname: Lu
authors.forename: Wen
authors.initials: W
authors.lastname: Yin
authors.forename: Li
authors.initials: L
authors.lastname: Ma
authors.forename: Zhongxue
authors.initials: Z
authors.lastname: Fu
mesh_terms: D000758:Anesthesia; D000818:Animals; D017704:Baroreflex / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D065128:Endothelin Receptor Antagonists / Q000494:pharmacology; D019332:Endothelin-1 / Q000031:analogs & derivatives* / Q000494:pharmacology; D007839:Functional Laterality / Q000187:drug effects; D007737:Kynurenine / Q000494:pharmacology; D008297:Male; D008845:Microinjections; D009842:Oligopeptides / Q000494:pharmacology; D010446:Peptide Fragments / Q000494:pharmacology*; D010456:Peptides, Cyclic / Q000494:pharmacology; D010656:Phenylephrine / Q000494:pharmacology; D010880:Piperidines / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D017552:Solitary Nucleus / Q000187:drug effects* / Q000502:physiology*; D013997:Time Factors; D014662:Vasoconstrictor Agents / Q000494:pharmacology
chemical_list: D065128:Endothelin Receptor Antagonists; D019332:Endothelin-1; D009842:Oligopeptides; D010446:Peptide Fragments; D010456:Peptides, Cyclic; D010880:Piperidines; D014662:Vasoconstrictor Agents; C114932:endothelin-1 (1-31); D010656:Phenylephrine; D007737:Kynurenine; C086539:BQ 788; C072247:cyclo(Trp-Asp-Pro-Val-Leu)