descending vasa recta (DVR) are terminal resistance vessels that arise from juxtamedullary efferent arterioles to distribute blood flow to the renal outer and inner medulla. Specialized smooth remnants (pericytes) surround DVR and impart contractility (37). We previously showed that stimulation of DVR pericytes by angiotensin II (ANG II) induces voltage-gated Ca~(2+) entry and activates Ca~(2+)-dependent chloride channels (CICa) (35, 49). High concentrations of ANG II (10 nmol/1) also inhibit K~+ conductance so that the combination of CaCl activation and K~+ channel suppression shifts the membrane potential toward the Cl~- ion equilibrium potential (E_(Cl)) to depolarize the cells (5, 34). A sizable fraction of DVR pericytes respond to ANG II stimulation with membrane potential oscillations. Similarly, during voltage clamp at -80 mV, spontaneous transient inward current (STIC) oscillations occur (35)
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