Please use this identifier to cite or link to this item:
http://hdl.handle.net/11452/21602
Title: | Restoration of blood pressure by centrally injected U-46619, a thromboxane A(2) analog, in hemorrhaged hypotensive rats: Investigation of different brain areas |
Authors: | Uludağ Üniversitesi/Tıp Fakültesi/Tıbbi Farmakoloji Anabilim Dalı. Uludağ Üniversitesi/Veteriner Fakültesi/Fizyoloji Anabilim Dalı. 0000-0002-5600-8162 Yalçın, Murat Savcı, Vahide AAG-6956-2021 57192959734 6603687024 |
Keywords: | Pharmacology & pharmacy Thromboxane A(2) Blood pressure Hemorrhagic shock Catecholamine Svasopressin Renin activity Sympatho-adrenomedullary outflow Paraventricular nucleus Vasopressin secretion Nitric-oxide CDP-choline Prostaglandins Activation Responses Perfusion Receptors |
Issue Date: | 2004 |
Publisher: | Karger |
Citation: | Yalçın, M. ve Savcı, V. (2004). “Restoration of blood pressure by centrally injected U-46619, a thromboxane A(2) analog, in hemorrhaged hypotensive rats: Investigation of different brain areas”. Pharmacology, 70(4), 177-187. |
Abstract: | In the present study, we investigated the cardiovascular effects of centrally injected U-46619, a thromboxane A(2) (TXA(2)) analog, and the central and peripheral mechanisms of these effects in hemorrhagic shock conditions. Hemorrhage was performed by withdrawing a total volume of 2.1 ml of blood/100 g body weight over a period of 10 min. Injections were made into the lateral cerebral ventricle (LCV), nucleus tractus solitarius (NTS), rostral ventrolateral medulla (RVLM) and paraventricular nucleus of hypothalamus (PVN). U-46619 (0.1, 1 and 2 mug) increased blood pressure and reversed hypotension in hemorrhagic shock. The pressor effect was dose- and time-dependent in all investigated brain areas. Heart rate changes were not significantly different in all groups. Pretreatment of rats with an injection of SQ-29548 ( 4 or 8 mug), a TXA(2) receptor antagonist, into the LCV, NTS, RVLM and PVN completely blocked the pressor effect of U-46619 (1 mug) injected into respective brain areas. Hemorrhage itself increased plasma adrenaline, noradrenaline, vasopressin levels and renin activity. U-46619 (1 mug) injected into the LCV, PVN, RVLM and NTS produced additional increases in these hormone levels and in renin activity. Intravenous pretreatments of rats with prazosin (0.5 mg/kg), an alpha(1)-adrenoceptor antagonist, [beta-mercapto-beta, beta-cyclopentamethylenepropionyl(1), O-Me-Tyr(2), Arg(8)]-vasopressin (10 mug/kg), a vasopressin V-1-receptor antagonist, or saralasin (250 mug/kg), an angiotensin II receptor antagonist, in hemorrhaged rats partially blocked the pressor response to U-46619 (1 mug) injected into the LCV, PVN, RVLM and NTS. Results show that centrally administered U-46619, a TXA(2) analog, increases blood pressure and reverses hypotension in hemorrhagic shock. Activation of central TXA(2) receptors mediates the pressor effect of the drug. Furthermore, the increases in plasma adrenaline, noradrenaline, vasopressin levels and renin activity are involved in these effects. |
URI: | https://doi.org/10.1159/000075546 https://www.karger.com/Article/Abstract/75546 http://hdl.handle.net/11452/21602 |
ISSN: | 0031-7012 |
Appears in Collections: | Scopus Web of Science |
Files in This Item:
There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.