Transcriptional profile of the rat cardiovascular system at single-cell resolution

We sought to characterize cellular composition across the cardiovascular system of the healthy Wistar rat, an important model in preclinical cardiovascular research. We performed snRNA-seq in 78 samples in 10 distinct regions including the four chambers of the heart, ventricular septum, sinoatrial node, atrioventricular node, aorta, pulmonary artery, and pulmonary veins, which produced 505,835 nuclei. We identified 26 distinct cell types and additional subtypes, with different cellular composition across cardiac regions and tissue-specific transcription for each cell type. Several cell subtypes were region-specific, including a subtype of vascular smooth muscle cells enriched in the large vasculature. We observed tissue-enriched cellular communication networks, including heightened Nppa - Npr1/2/3 signaling in the sinoatrial node. The existence of tissue-restricted cell types suggests regional regulation of cardiovascular physiology. Our detailed transcriptional characterization of each cell type offers the potential to identify novel therapeutic targets and improve preclinical models of cardiovascular disease. Overall design: 78 samples which passed QC are included here. All samples are from healthy Wistar rat cardiovascular tissue, collected from specific tissue regions. The rats are all male 17 week old animals. Multiple tissue region samples were collected from each individual rat, and a total of 16 individual rats were used to collect the snRNA-seq data in this study. Nuclei were isolated from each sample and were used to prepare a 10x 3' v2 library for snRNA-seq.