Desensitization of myocardial beta-adrenergic receptors and deterioration of left ventricular function after brain death.
Journal Article (Journal Article)
Brain death often results in a series of hemodynamic alterations that complicate the treatment of potential organ donors before transplantation. The deterioration of myocardial performance after brain death has been described; however, the pathophysiologic process of the myocardial dysfunction that occurs after brain death has not been elucidated. This study was designed to analyze the function of the myocardial beta-adrenergic receptor and the development of left ventricular dysfunction in a porcine model of experimental brain death. Analysis of the beta-receptor included determination of receptor density and adenylate cyclase activity after stimulation independently at the receptor protein, the G protein, and the adenylate cyclase moiety. Myocardial beta-receptor density did not change after the induction of brain death. A decrease in stimulated adenylate cyclase activity was observed within the first hour after brain death at the level of the beta-receptor, the G protein, and the adenylate cyclase moiety, which suggests the occurrence of rapid desensitization of beta-receptor function. Significant deterioration of myocardial performance also occurred within the first hour after brain death, represented by a decrease in preload-recruitable stroke work compared with the baseline value. The deterioration of myocardial performance after brain death correlates temporally with desensitization of the myocardial beta-receptor signal transduction system. The mechanism of impairment appears to be localized to the adenylate cyclase moiety itself.
Full Text
Duke Authors
Cited Authors
- D'Amico, TA; Meyers, CH; Koutlas, TC; Peterseim, DS; Sabiston, DC; Van Trigt, P; Schwinn, DA
Published Date
- September 1995
Published In
Volume / Issue
- 110 / 3
Start / End Page
- 746 - 751
PubMed ID
- 7564442
International Standard Serial Number (ISSN)
- 0022-5223
Digital Object Identifier (DOI)
- 10.1016/s0022-5223(95)70107-9
Language
- eng
Conference Location
- United States