Accession Number:

ADA159810

Title:

The Role of Endorphins in the Pathophysiology of Hemorrhagic and Endotoxic Shock in the Subhuman Primate.

Descriptive Note:

Annual rept. 15 Sep 81-1 Sep 82,

Corporate Author:

IOWA UNIV IOWA CITY COLL OF MEDICINE

Report Date:

1982-09-01

Pagination or Media Count:

20.0

Abstract:

In order to investigate the role of endorphins short for endogenous morphine-like substances in the pathophysiology of cardivascular depression in primate shock we subjected cynomulgus monkeys to hemorrhage or endotoxemia. Blockade of opiate receptors with naloxone improved cardiovascular performancemean arterial pressure and left ventricular contractility and survival in both endotoxic and hemorrhagic shock--provided pH and temperature were maintained. Physiological antagonism of endorphins with thyrotropin-releasing hormone resulted in improved cardiovascular function in both forms of shock and increased survival in hemorrhage. Intact adrenal glands and cardiac autonomic innervation are necessary for naloxones full effects to obtain, at least in the dog. Central nervous system injection of an endorphin produced bradycardia and hypotension which were reversed by naloxone, but central injection of naloxone did not reverse hemorrhagic shock in the monkey. Opiates failed to release histamine in vivo rat and in vitro rat peritoneal mast cells. The mechanisms of endorphin-mediated cardiovascular dysfunction in shock and its reversal by naloxone are central and not peripheral and involve central nervous system centers controlling autonomic nervous system function or integration.

Subject Categories:

  • Pharmacology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE