Interaction of the sympathetic nervous system with vasopressin and renin in the maintenance of blood pressure.

Abstract

SUMMARY To evaluate the partial contributions and interaction of three vasopressor systems in blood pressure maintenance, nephrectomized rats and rats with intact kidneys were submitted sequentially to catecholamine depletion, elimination of vasopressin's vasoconstrictor action, and (for those with kidneys in situ) angiotensin blockade. Catecholamine depletion decreased blood pressure and stimulated vasopressin levels in all rats, but significantly more so in the anephric ones. Subsequent injection of an antagonist to the vasopressor effect of vasopressin produced a lasting fall of blood pressure in anephric rats, but only transient fall in those with intact kidneys. Infusion of teprotide -an angiotensin converting enzyme inhibitor -in the latter animals also produced transient blood pressure fall, but if this were followed by injection of the vasopressin antagonist, the pressure remained low for several hours. Blood pressure levels were closely correlated with those of plasma catecholamines throughout these maneuvers. Catecholamine levels were inversely correlated with those of plasma vasopressin, which were far greater in anephric rats through both stimulation and accumulation. Plasma renin activity was increasingly stimulated by falling blood pressure after each maneuver in rats with intact kidneys. Thus, it appears that in the resting state the sympathetic nervous system is more involved in the maintenance of blood pressure, whereas vasopressin and renin are important backup mechanisms. The present experiments were designed to evaluate the contribution of each one of these three vasopressor systems to the maintenance of normal blood pressure. Catecholamine depletion and bilateral nephrectomy were intended to produce conditions comparable -albeit extreme -to those likely to be encountered in the therapy of human hypertension, e.g., treatment with sympatholytic agents and advanced renal failure. Under these conditions, we studied the interaction and relationships of catecholamines, vasopressin, and the renin-angiotensin system.

The contribution of vasopressin and angiotensin to the maintenance of blood pressure after autonomic blockade.

“…The renin-angiotensin system and AVP are reported to be equally important for BP maintenance during water deprivation 6 and in chemically sympathectomized rats. 23 Our results after total autonomic blockade agree with those of Houck et al, 12 who studied BP regulation in anesthetized dogs after ganglionic blockade with hexamethonium.…”

Vasopressin V1a and V1b Receptors: From Molecules to Physiological Systems

“…In the CNS, AVP is reported to stimulate sympathetic nerve activity (170,382), and consequently affects lipid metabolism in peripheral tissues such as liver and fat. AVP also participates in lipid metabolism of adipose tissues directly and indirectly by stimulating several hormone secretions (483).…”

Neonatal capsaicin treatment impairs vasopressin‐mediated blood pressure recovery following acute hypotension

“…Present evidence indicates that the reninangiotensin system, sympathetic nervous system and vasopressin may all interact and contribute to the maintenance of arterial blood pressure in normal (Gavras et al, 1982) and water-deprived states (Andrews & Brenner, 1981). We therefore used an angiotensin-converting enzyme inhibitor (captopril) and a ganglion blocker (pentolinium) to achieve an acute hypotension in which a possible influence of vasopressin on blood pressure could be discerned.…”