Effects of hypercapnia on renal nerve activity.

We investigated the response of renal nerve activity (RNA) to hypercapnia and assessed the contribution of the peripheral chemoreceptors to the response of RNA in anesthetized and artificially ventilated cats. RNA and arterial pressure were recorded at four levels of PETCO2 with hyperoxia in intact and in peripheral chemoreceptor denervated cats. In intact cats, RNA increased progressively with increasing PETCO2, while no consistent change in arterial pressure was observed. In peripheral chemoreceptor denervated cats, the response of RNA to increasing PETCO2 was totally abolished. These results suggest that the peripheral chemoreceptors play an important role in increasing RNA during hypercapnia.