Effect of norepinephrine and renal denervation on renal PGE2 and kallikrein in rats

Abstract
To investigate the influence of the sympathetic nervous system on the renal prostaglandin [PG] and kallikrein systems, the effects of norepinephrine (NE) infusion and renal denervation on the urinary excretion of PGE2 and kallikrein were studied in unanesthetized rats. Relative to sham controls, in rats infused with NE at 15 .mu.g/h i.p. for 8 days, plasma NE was increased 10-fold, systolic blood pressure by 20-34 mmHg, and urinary PGE2 excretion 2-fold, but urinary kallikrein excretion was not altered. NE infusion produced a transient natriuresis and a slight reduction in body weight gain. Relative to values in sham-operated rats, bilateral renal denervation reduced catecholamine content of the kidneys to < 10% of control 10 and 30 days after surgery, but had no effect on urinary excretion of either PGE2 or kallikrein. Evidently, in unanesthetized rats, renal kallikrein is not affected by either a sustained increased in plasma norepinephrine or by chronic renal artery denervation; basal renal PGE2 production is not regulated by basal renal nerve activity; and prolonged elevation of plasma norepinephrine causes, either directly or indirectly, a sustained induction of PGE2 production by the kidney.