Investigation of the mechanisms of cyclooxygenase-mediated mechanoreflex sensitization in a rat model of simulated peripheral artery disease.

Investigation of the mechanisms of cyclooxygenase-mediated mechanoreflex sensitization in a rat model of simulated peripheral artery disease. Am J Physiol Heart Circ Physiol. 2019 Aug 30;: Authors: Butenas ALE, Hopkins TD, Rollins KS, Felice KP, Copp SW Abstract Mechanical and metabolic stimuli within contracting skeletal muscles reflexly increase sympathetic nervous system activity and blood pressure. That reflex, termed the exercise pressor reflex, is exaggerated in peripheral artery disease (PAD) patients and in a rat PAD model with a chronically ligated femoral artery. The cyclooxygenase (COX) pathway contributes to the exaggerated pressor response during rhythmic skeletal muscle contractions in PAD patients but the specific mechanism(s) of the COX-mediated exaggeration is not known. In decerebrate, unanesthetized rats with a chronically ligated femoral artery ("ligated" rats), we hypothesized that hindlimb arterial injection of the COX inhibitor indomethacin would reduce the pressor response during 1 Hz dynamic hindlimb skeletal muscle stretch; a model of the activation of the mechanical component of the exercise pressor reflex (i.e., the mechanoreflex). In ligated rats (n=7), indomethacin reduced the pressor response during stretch (control: 30±4, indomethacin: 12±3 mmHg; p<0.01) whereas there was no effect in rats with "freely perfused" femoral arteries (n=6, control: 18±5, indomethacin: 17±5 mmHg; p=0.87). In ligated r...
Source: American Journal of Physiology. Heart and Circulatory Physiology - Category: Physiology Authors: Tags: Am J Physiol Heart Circ Physiol Source Type: research