Journal
AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY
Volume 284, Issue 6, Pages H1985-H1994Publisher
AMER PHYSIOLOGICAL SOC
DOI: 10.1152/ajpheart.01145.2002
Keywords
regional blood flow; fluorescent microspheres
Ask authors/readers for more resources
The systemic and regional hemodynamics effects of ANG-(1-7) were examined in urethane-anesthetized rats. The blood flow distribution (kidneys, skin, mesentery, lungs, spleen, brain, muscle, and adrenals), cardiac output, and total peripheral resistance were investigated by using fluorescent microspheres. Blood pressure and heart rate were recorded from the brachial artery. ANG-(1-7) infusion (110 fmol.min(-1).10 min(-1) iv) significantly increased blood flow to the kidney (5.10 +/- 1.07 to 8.30 +/- 0.97 ml.min(-1).g(-1)), mesentery (0.73 +/- 0.16 to 1.17 +/- 0.49 ml.min(-1).g(-1)), brain (1.32 +/- 0.44 to 2.18 +/- 0.85 ml.min(-1).g(-1)), and skin (0.07 +/- 0.02 to 0.18 +/- 0.07 ml.min(-1).g(-1)) and the vascular conductance in these organs. ANG-(1-7) also produced a significant increase in cardiac index (30%) and a decrease in total peripheral resistance (2.90 +/- 0.55 to 2.15 +/- 0.28 mmHg.ml(-1).min.100 g). Blood flow to the spleen, muscle, lungs, and adrenals, as well as the blood pressure and heart rate, were not altered by the ANG-(1-7) infusion. The selective ANG-(1-7) antagonist A-779 reduced the blood flow in renal, cerebral, mesenteric, and cutaneous beds and blocked the ANG-(1-7)-induced vasodilatation in the kidney, mesentery, and skin, suggesting a significant role of endogenous ANG-(1-7) in these territories. The effects of ANG-(1-7) on the cerebral blood flow, cardiac index, systolic volume, and total peripheral resistance were partially attenuated by A-779. A high dose of ANG-(1-7) (11 pmol.min(-1).10 min(-1)) caused an opposite effect of that produced by the low dose. Our results show for the first time that ANG-(1-7) has a previously unsuspected potent effect in the blood flow distribution and systemic hemodynamics.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available