Formation and actions of 20-hydroxyeicosatetraenoic acid in rat renal arterioles. Am J Physiol 1996 Jan;270(1 Pt 2):R217-27
Date
01/01/1996Pubmed ID
8769805DOI
10.1152/ajpregu.1996.270.1.R217Scopus ID
2-s2.0-0030028233 (requires institutional sign-in at Scopus site) 264 CitationsAbstract
The present study examined whether preglomerular arterioles of the rat produce 20-hydroxyeicosatetraenoic acid (20-HETE) and whether 20-HETE is vasoactive on these vessels. Raf preglomerular arterioles produced 20-HETE (4.8 +/- 1.0 pmol.min-1.mg-1, n = 7) and, to a lesser extent, 14-, 15-, 11-, and 12-dihydroxyeicosatetraenoic acid, 6-ketoprostaglandin F/alpha and prostaglandin E2 when incubated with [14C]larachidonic acid. The results of immunoblotting and reverse-transcription polymerase chain reaction experiments indicate that these vessels express mRNA and protein for a P-450 4A2 enzyme. With the use of a rat juxtamedullary nephron microvascular preparation perfused in vitro with a cell-free media, addition of 20-HETE (1 nM-1 microM) to the bath reduced the diameter of proximal and distal portions of the efferent arterioles. At a concentration of 1 microM, the diameter of the proximal and distal portions of the afferent arteriole fell by 14 +/- 1 and 16 +/- 3% after 20-HETE. The response to 20-HETE (1 microM) was not altered by blockade of cyclooxygenase, lipoxygenase, and p-450 pathways. Blockade of the large-conductance Ca(2+)-activated K+ channel with tetraethylammonium (1 mM) reduced the diameter of afferent arterioles by 10% and blocked the vasoconstrictor response to 20-HETE (1 microM). These results indicate that 20-HETE is an endogenous constrictor of preglomerular arterioles and suggest a role for the P-450 4A2 enzyme in the regulation of renal vascular tone.
Author List
Imig JD, Zou AP, Stec DE, Harder DR, Falck JR, Roman RJMESH terms used to index this publication - Major topics in bold
AnimalsArachidonic Acid
Arterioles
Base Sequence
Blood Vessels
Hydroxyeicosatetraenoic Acids
Isomerism
Male
Microcirculation
Molecular Probes
Molecular Sequence Data
Rats
Rats, Sprague-Dawley
Renal Circulation
Tetraethylammonium
Tetraethylammonium Compounds
Vasoconstriction