Contribution of cytochrome p450 4a1 and 4a2 to vascular 20
-hydroxyeicosatetraenoic acid synthesis in the rat kidney.
Wang, Mong-Heng, Hui Guan, Xuandai Nguyen, Barbara A. Zand, Alberto
Nasjletti, Michal Laniado Schwartzman.
Department of Pharmacology, New York Medical College, Valhalla, NY
10595
APStracts 5:0184F, 1998.
20-hydroxyeicosatetraenoic acids (20-HETE), a biologically active
cytochrome P450 (CYP) metabolite of arachidonic acid in the rat
kidney, can be catalyzed by CYP4A isoforms including CYP4A1, CYP4A2,
and CYP4A3. To determine the contribution of CYP4A isoforms to renal
20-HETE synthesis, specific antisense oligonucleotides (ODNs) were
developed and their specificity was examined in vitro in Sf9 cells
expressing CYP4A isoforms and in vivo in Sprague-Dawley rats.
Administration of CYP4A2 antisense ODNs (167 nmol/Kg body weight/day
for 5 days, iv) decreased vascular 20-HETE synthesis by 48% with no
effect on tubular synthesis, whereas administration of CYP4A1
antisense ODNs inhibited vascular and tubular 20-HETE synthesis by 52
and 40 %, respectively. RT/PCR of microdissected renal microvessel
RNA indicated the presence of CYP4A1, CYP4A2 and CYP4A3 mRNAs and a
CYP4A1-immunoreactive protein was detected by Western analysis of
microvessel homogenates. Blood pressure measurements revealed a
reduction of 17+/-6 and 16+/-4 mmHg in groups receiving CYP4A1 and
4A2 antisense ODNs, respectively. These studies implicate CYP4A1 as a
major 20-HETE synthesizing activity in the rat kidney and further
document the feasibility of using antisense ODNs to specifically
inhibit 20-HETE synthesis and thereby investigate its role in the
regulation of renal function and blood pressure.
Received 17 July 1998; accepted in final form 8 October 1998.
APS Manuscript Number F172-8.
Article publication pending Am. J. Physiol. (Renal Physiology).
ISSN 1080-4757 Copyright 1998 The American Physiological Society.
Published in APStracts on 10 November 1998