RVLM C1 Neurons Innervate Sacral as well as Thoracolumbar Autonomic Preganglionic Neurons in the Rat

Abstract

We examined the distribution of axons throughout the spinal cord of the rat that were either immunoreactive for the adrenaline-synthesizing enzyme, phenylethanolamine N-methyltransferase (PNMT), or derived from medullary C1 neurons, one of the three groups of neurons in the brain that synthesize PNMT. We observed that PMNT-immunoreactive axons, as well as C1 axons labelled with GFP from viral transduction, innervate most, but not all, sympathetic preganglionic neurons in the thoracolumbar spinal cord. GFP-positive C1 axons provided innervation to sympathetic preganglionic neurons that expressed cocaine and amphetamine regulated transcript, an accepted marker of sympathetic vasomotor neurons...