Afferent arteriolar autoregulation was assessed using the in vitro blood-perfused juxtamedullary nephron preparation. A: The afferent arteriolar response to alterations in renal perfusion pressure was measured in SS rats treated with a 0.3% salt diet (Pre-HT SS, squares with a solid line), SS rats that are heterozygous with one wild-type or reference allele of Ets1 (SSEts1+/− rats) fed with a 0.3% salt diet (Pre-HT SSEts1+/−, triangles with solid line), SS rats treated with 4% high salt diet (HT SS, squares with a dashed line), or SSEts1+/− rats fed with a 4% salt diet (HT SSEts1+/−, triangles with a dashed line) over 7 days. B: Data were normalized as percent of the control diameter at 100 mm Hg. Values were expressed as mean ± SEM. *p-value < 0.05 versus control diameter in the same group; #p-value < 0.05 versus Pre-HT SS kidneys at the same perfusion pressure; n=6.