Do renal nerves chronically influence renal function and arterial pressure in spinal rats?

Area of Science:

• Physiology
• Nephrology
• Cardiovascular Science

Background:

• Renal nerve activity acutely impacts renal function in rats with cervical spinal cord transection (CST).
• The chronic influence of renal nerves on renal and cardiovascular function in CST rats remains unclear.

Purpose of the Study:

• To test the hypothesis that renal nerves chronically influence renal and cardiovascular function in rats following cervical spinal cord transection (CST).

Main Methods:

• Conscious Sprague-Dawley rats were divided into three groups: renal denervated plus CST (RDNX + CST), sham RDNX plus CST (sham + CST), and intact controls.
• Renal denervation or sham surgery was followed 8 days later by CST or sham CST.
• Mean arterial pressure (MAP), plasma renin activity (PRA), urine flow, urinary sodium excretion, and urine pH were monitored post-surgery.

Main Results:

• MAP decreased significantly in both RDNX + CST and sham + CST groups one day after CST.
• PRA decreased by approximately 50% one day after CST and remained depressed throughout the study, with no difference between CST groups.
• No significant differences in measured renal or cardiovascular variables were observed between the RDNX + CST and sham + CST groups post-CST.

Conclusions:

• The chronic effects of renal nerves on renal function and arterial pressure in rats with cervical spinal cord transection were not evident in this study.
• These findings suggest that chronic renal denervation does not alter the cardiovascular or renal response to CST in rats.