The affinity of vascular vasopressin receptors was studied to determine its role in altered vascular contractile sensitivity in deoxycorticosterone acetate (DOCA)-salt hypertension. Ring segments of rat mesenteric arteries were used to study vascular vasopressin receptors. Male Wistar rats were given subcutaneous injections of DOCA and 1% NaCl in the drinking water. Mesenteric arteries from hypertensive rats had a reduced contractile sensitivity to arginine vasopressin (AVP) and lysine vasopressin (LVP). The order of potency of vasopressin receptor agonists (AVP > LVP > oxytocin) was the same in arteries from hypertensive compared with normotensive animals. The affinity of the vasopressin receptor antagonist [deamino-Pen1,O-Me- Tyr2,Arg8] vasopressin, and the affinities of the vasopressin receptor agonists AVP and LVP were not altered during developing DOCA-salt hypertension. There was no change in contractile sensitivity to norepinephrine and KCl in arteries from hypertensive rats. The reduced vasopressin contractile sensitivity is not due to a change in vasopressin receptor affinity but may be a compensatory response to elevated blood pressure. These data suggest that increased vascular sensitivity does not contribute to elevated blood pressure during the developing stage of DOCA- salt hypertension.
|Original language||English (US)|
|Journal||American Journal of Physiology - Heart and Circulatory Physiology|
|Issue number||6 31-6|
|State||Published - 1992|
All Science Journal Classification (ASJC) codes
- Cardiology and Cardiovascular Medicine
- Physiology (medical)