Protein kinase C epsilon contributes to chronic mechanoreflex sensitization in rats with heart failure

figure legend Skeletal muscle contraction leads to exaggerated reflex increases in sympathetic nerve activity in heart failure patients with reduced ejection fraction (HF-rEF) which raises cardiovascular risk and impairs exercise tolerance. This is partly due to chronic sensitization of mechanically sensitive group III/IV muscle afferents via Gq protein-coupled thromboxane A2 (TxA2) and bradykinin B2 receptor signalling. The specific Gq protein-linked signalling mechanisms underlying this sensitization have not been fully explored, though indirect evidence strongly suggests the involvement of either inositol 1,4,5-trisphosphate (IP3) receptors and/or protein kinase C epsilon (PKC epsilon). Our findings demonstrate that PKC epsilon, but not IP3 receptors, within sensory endings of thin fibre muscle afferents play a role in the mechanoreflex sensitization in HF-rEF rats. image