1A-779 attenuates angiotensin-(1-7) depressor response in salt-induced hypertensive rats.
Chronic infusion of angiotensin-(1-7) [Ang-(1-7)] lowers blood pressure in salt-induced and spontaneously hypertensive (SHR) rats. In the present study, we have examined the acute effect of Ang-(1-7) in salt-induced hypertension using Dahl salt-sensitive rats placed on low (0.3%) or high (8.0% NaCl) salt diets for 2 weeks. Rats fed a high salt diet showed a greater rise in BP than those fed a low salt diet. Ang-(1-7) (24 microg/kg) reduced mean arterial pressure (MAP), enhanced the release of prostacyclin and nitric oxide, and suppressed thromboxane A(2) levels. A-779 (48 microg/kg, i.v), a selective Ang-(1-7) antagonist, partially blocked these effects of Ang-(1-7). The Ang-(1-7)-induced depressor response observed in these animals was related to an increase in vasodilatory prostanoids, a decrease in the constrictor prostanoid thromboxane A(2), and an increase in nitric oxide levels in both plasma and isolated aortic rings.
Bayorh
Mohamed A
MA
Department of Pharmacology & Toxicology, Morehouse School of Medicine, 720 Westview Drive, S.W., Atlanta, GA 30310-1495, USA. bayorh@msm.edu
Eatman
Danita
D
Walton
Marcus
M
Socci
Robin R
RR
Thierry-Palmer
Myrtle
M
Emmett
Nerimiah
N
D015121:6-Ketoprostaglandin F1 alpha / Q000097:blood; D000803:Angiotensin I / Q000378:metabolism*; D000804:Angiotensin II / Q000031:analogs & derivatives / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure; D001835:Body Weight; D006152:Cyclic GMP / Q000378:metabolism; D015232:Dinoprostone / Q000097:blood; D011464:Epoprostenol / Q000494:pharmacology*; D006973:Hypertension / Q000378:metabolism*; D008297:Male; D009569:Nitric Oxide / Q000097:blood / Q000378:metabolism / Q000494:pharmacology*; D010446:Peptide Fragments / Q000378:metabolism* / Q000494:pharmacology*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology; D051381:Rats; D020303:Rats, Inbred Dahl; D011918:Rats, Inbred SHR; D012492:Salts / Q000494:pharmacology*; D013928:Thromboxane A2 / Q000494:pharmacology*; D013929:Thromboxane B2 / Q000097:blood; D013997:Time Factors
C092006:7-Ala-angiotensin (1-7); D010446:Peptide Fragments; D010975:Platelet Aggregation Inhibitors; D012492:Salts; D000804:Angiotensin II; D009569:Nitric Oxide; D013929:Thromboxane B2; D013928:Thromboxane A2; D015121:6-Ketoprostaglandin F1 alpha; D000803:Angiotensin I; D011464:Epoprostenol; D006152:Cyclic GMP; C118790:angiotensin I (1-7); D015232:Dinoprostone