Vasopressin and atrial natriuretic peptide release in cardiopulmonary denervated dogs

To assess the effect of cardiopulmonary denervation on the release of arginine vasopressin (AVP) and atrial natriuretic peptide (ANP), either hemorrhage (1.0 ml.kg-1.min-1, for 40 min) or an infusion of 3% dextran in lactated Ringer solution (RL) (3% dextran in RL, 1.0 ml.kg-1.min-1, for 40 min) was carried out in chronic cardiopulmonary denervated (CPD, n = 7) and sham-operated (SO, n = 7) dogs under anesthesia. Plasma AVP increased significantly in both groups during hemorrhage, but its rise was significantly attenuated in CPD dogs. Plasma ANP decreased similarly during hemorrhage in both groups. An infusion of 3% dextran in RL decreased significantly plasma AVP during its whole period in SO dogs, but AVP release was only suppressed in the late period in SO dogs. Plasma ANP increased significantly during its infusion in both groups. These results indicate that cardiopulmonary denervation may attenuate the release of AVP in response to either hemorrhage or blood volume expansion but may not affect the release of ANP in response to the blood volume change. Moreover, a large increase in plasma ANP may attenuate the release of AVP.