Osmolality-regulated arginine vasopressin release in conscious dogs. Evidence for dopaminergic or opioid modulation?

Abstract

Experiments were performed in conscious dogs, in order to study the possibility of dopaminergic or opioid modulation of the osmolality-regulated release of AVP. Hypertonic saline (20%), infused during a period of 2 h at a rate of 0.03 ml.kg-1.min-1, induced a significant AVP response, which was not influenced by prior administration of bromocriptine or naloxone. Data presented in this report, therefore, are not in support of a dopaminergic or opioid modulation of the osmolality-regulated AVP release in dogs. The results demonstrate a great consistency in individual plasma osmolality-plasma AVP relationships, next to a large inter-individual variation.