Faculty Collaboration Database

Response of resistance arteries to reduced PO2 and vasodilators during hypertension and elevated salt intake. Am J Physiol 1997 Aug;273(2 Pt 2):H869-77

Date

08/01/1997

Pubmed ID

9277505

DOI

10.1152/ajpheart.1997.273.2.H869

Scopus ID

2-s2.0-0030828941 (requires institutional sign-in at Scopus site)   78 Citations

Abstract

This study assessed vasodilator responses in skeletal muscle resistance arteries (100-250 microns) from rats with chronic (4-8 wk) reduced renal mass (RRM) hypertension and normotensive sham-operated controls on a high (4% NaCl; HSSHAM)- or low (0.4% NaCl; LSSHAM)-salt diet. Arteries from RRM hypertensive rats [normal and high-salt diet (HSRRM)] and a separate group of spontaneously hypertensive rats exhibited an impaired dilation in response to reduced PO2 compared with those of their normotensive controls. Prostacyclin release, assessed by radio-immunoassay for 6-ketoprostaglandin F1 alpha, increased significantly in response to reduced PO2, but was unaffected by hypertension or salt intake. Dilator responses to acetylcholine and the prostacyclin analog iloprost were significantly reduced in both HSRRM and HSSHAM compared with LSSHAM rats. Dilation in response to direct activation of adenylate cyclase with forskolin or guanylate cyclase with the nitric oxide donor sodium nitroprusside was not significantly different in HSRRM, HSSHAM, and LSSHAM rats. These results indicate that hypoxic dilation is impaired in skeletal muscle resistance arteries of hypertensive rats and that chronic high-salt diet alone leads to impaired vasodilator responses in resistance arteries of normotensive animals, possibly via abnormalities in membrane function or G protein signaling rather than impaired second-messenger function.

Author List

Liu Y, Fredricks KT, Roman RJ, Lombard JH

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

Animals
Arteries
Blood Pressure
Diet, Sodium-Restricted
Epoprostenol
Hypertension
Male
Nephrectomy
Oxygen
Partial Pressure
Rats
Rats, Inbred SHR
Rats, Inbred WKY
Rats, Sprague-Dawley
Vascular Resistance
Vasodilator Agents