Effect of Denervation on the Leucine-Enkephalin Content of the Adrenal Gland of Spontaneously Hypertensive Rats (SHRSP)

Abstract

Enkephalins are known to inhibit the release of catecholamines from sympathetic nerve endings. Thus a difference in their turnover rate between SHRSP and normotensive rats (WKY) could contribute to the altered sympathetic activity in SHRSP. One week after denervation which inhibits release of leucine-enkephalin (L-ENK), but not synthesis and processing of the L-ENK precursor, L-ENK increased with the same relative extent in both strains of rats, starting from a lower basal concentration in 7 weeks old SHRSP. In adult rats there was no difference between SHRSP and WKY before and after denervation respectively. It is concluded that the lower content of L-ENK in young SHRSP is caused by an increased release.