Faculty Collaboration Database

Elevated renovascular tone in young spontaneously hypertensive rats. Role of cytochrome P-450. Hypertension 1993 Sep;22(3):357-64

Date

09/01/1993

Pubmed ID

8349328

DOI

10.1161/01.hyp.22.3.357

Scopus ID

2-s2.0-0027301319 (requires institutional sign-in at Scopus site)   111 Citations

Abstract

The present study examined the role of cytochrome P-450 metabolites of arachidonic acid in elevating renal vascular resistance in young spontaneously hypertensive rats (SHR). Differences in vascular tone were assessed in the preglomerular vasculature of 3- to 4-week-old prehypertensive SHR (n = 11) and normotensive Wistar-Kyoto (WKY, n = 10) and Wistar-Lewis (n = 10) rats. Pressure-diameter relations to changes in renal perfusion pressure were compared using the juxtamedullary nephron microvascular preparation perfused in vitro with a physiological salt solution. At a pressure of 60 mm Hg, the basal diameters of the interlobular arteries and proximal and distal afferent arterioles of the SHR averaged 43 +/- 2, 17 +/- 0.3, and 11 +/- 0.4 microns, respectively. The diameters of the interlobular arteries and afferent arterioles were 9% to 14% smaller than those of corresponding vessels in WKY and Wistar-Lewis rats. Addition of P-450 inhibitors, ketoconazole (100 mumol/L) or 7-ethoxyresorufin (1 mumol/L), to the perfusate dilated the afferent arteriole of SHR by 7% to 12%, whereas it increased the diameter by only 0% to 6% in control rats and significantly reduced the differences in the pressure-diameter relation in the preglomerular vasculature of SHR and control rats. Inhibitors of P-450 eliminated the contractile response of afferent arterioles to increases in renal perfusion pressure in all three groups. Removal of calcium from the perfusate eliminated differences in the diameters of the preglomerular vasculature in SHR and normotensive rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Author List

Imig JD, Falck JR, Gebremedhin D, Harder DR, Roman RJ

MESH terms used to index this publication - Major topics in bold

Acetylcholine
Animals
Arachidonic Acids
Arterioles
Blood Pressure
Cytochrome P-450 Enzyme Inhibitors
Cytochrome P-450 Enzyme System
Ketoconazole
Kidney
Microsomes
Muscle Tonus
Muscle, Smooth, Vascular
Norepinephrine
Rats
Rats, Inbred SHR
Rats, Inbred WKY
Rats, Wistar
Vasoconstriction
Vasodilation