Novel target identification using single cell sequencing and electrophysiology of cardiac sympathetic neurons in disease

Abstract

Word Count: 4421 (Limit: 5000) Methods word count: 2047 (Limit: 3000) Abstract (150 words)The activity of cardiac sympathetic nerves from the stellate ganglia is increased in many cardiovascular diseases contributing to the pathophysiology. However, the mechanisms underlying this are unknown. Moreover, clinical studies show their surgical removal is an effective treatment, despite the biophysical properties of these neurons being largely unstudied. We demonstrate that stellate ganglia neurons from prehypertensive spontaneously hypertensive rats are hyperactive and describe in detail their electrophysiological phenotype guided by single cell RNA-sequencing, molecular biology, perforated patch-clamp and computational modelling to uncover the underlying mechanism.The expression of key transcripts is confirmed in human stellate ganglia. We demonstrate the contribution of a plethora of ion channels to stellate ganglia neuronal firing, and show that hyperexcitability is curbed by M-current activators, non-selective sodium current blockers or inhibition of Nav1.1-1.3, Nav1.6 or INaP. These findings have important implications for target discovery to reduce cardiac sympathetic neuron activity pharmacologically without resorting to surgery.