{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T03:43:21Z","timestamp":1774323801504,"version":"3.50.1"},"reference-count":0,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"4","content-domain":{"domain":["www.ahajournals.org"],"crossmark-restriction":true},"short-container-title":["Circulation Research"],"published-print":{"date-parts":[[1992,10]]},"abstract":"<jats:p>Membrane currents from single smooth muscle cells enzymatically isolated from canine renal artery were recorded using the patch-clamp technique in the whole-cell and cell-attached configurations. These cells exhibited a mean resting potential, input resistance, membrane time constant, and cell capacitance of -51.8 +\/- 2.1 mV, 5.2 +\/- 0.98 G omega, 116.2 +\/- 16.4 msec, and 29.1 +\/- 2.0 pF, respectively. Inward current, when elicited from a holding potential of -80 mV, activated near -50 mV, reached a maximum near 0 mV and was sensitive to the dihydropyridine agonist Bay K 8644 and dihydropyridine antagonist nisoldipine. Two components of macroscopic outward current were identified from voltage-step and ramp depolarizations. The predominant charge carrier of the net outward current was identified as K+ by tail-current experiments (reversal potential, -61.0 +\/- 0.8 mV in 10.8 mM [K+]o 0 mM [K+]i). The first component was a small, low-noise, voltage- and time-dependent current that activated between -40 and -30 mV (IK(dr)), and the second component was a larger, noisier, voltage- and time-dependent current that activated at potentials positive to +10 mV (IK(Ca)). Both IK(dr) and IK(Ca) displayed little inactivation during long (4-second) voltage steps. IK(Ca) and IK(dr) could be pharmacologically separated by using various Ca2+ and K+ channel blockers. IK(Ca) was substantially inhibited by external NiCl2 (500 microM), CdCl2 (300 microM), EGTA (5 mM), tetraethylammonium (Ki at +60 mV, 307 microM), and charybdotoxin (100 nM) but was insensitive to 4-aminopyridine (0.1-10 mM). IK(dr) was inhibited by 4-aminopyridine (Ki at +10 mV, 723 microM) and tetraethylammonium (Ki at +10 mV, 908 microM) but was insensitive to external NiCl2 (500 microM), CdCl2 (300 microM), EGTA (5 mM), and charybdotoxin (100 nM). Two types of single K+ channels were identified in cell-attached patches. The most abundant K+ channel that was recorded exhibited voltage-dependent activation, was blocked by external tetraethylammonium (250 microM), and had a large single-channel conductance (232 +\/- 12 pS with 150 mM K+ in the patch pipette, 130 +\/- 17 pS with 5.4 mM K+ in the patch pipette). The second channel was also voltage dependent, was blocked by 4-aminopyridine (5 mM), and exhibited a smaller single-channel conductance (104 +\/- 8 pS with 150 mM K+ in the patch pipette, 57 +\/- 6 pS with 5.4 mM K+ in the patch pipette). These results suggest that depolarization of canine renal artery cells opens dihydropyridine-sensitive Ca2+ channels and at least two K+ channels.(ABSTRACT TRUNCATED AT 400 WORDS)<\/jats:p>","DOI":"10.1161\/01.res.71.4.745","type":"journal-article","created":{"date-parts":[[2012,6,12]],"date-time":"2012-06-12T00:47:05Z","timestamp":1339462025000},"page":"745-758","update-policy":"https:\/\/doi.org\/10.1161\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":52,"title":["Ionic currents in single smooth muscle cells of the canine renal artery."],"prefix":"10.1161","volume":"71","author":[{"given":"C H","family":"Gelband","sequence":"first","affiliation":[{"name":"Department of Physiology, University of Nevada School of Medicine, Reno 89557."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J R","family":"Hume","sequence":"additional","affiliation":[{"name":"Department of Physiology, University of Nevada School of Medicine, Reno 89557."}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"276","container-title":["Circulation Research"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.ahajournals.org\/doi\/pdf\/10.1161\/01.RES.71.4.745","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,5,12]],"date-time":"2024-05-12T20:51:49Z","timestamp":1715547109000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.ahajournals.org\/doi\/10.1161\/01.RES.71.4.745"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1992,10]]},"references-count":0,"journal-issue":{"issue":"4","published-print":{"date-parts":[[1992,10]]}},"alternative-id":["10.1161\/01.RES.71.4.745"],"URL":"https:\/\/doi.org\/10.1161\/01.res.71.4.745","relation":{},"ISSN":["0009-7330","1524-4571"],"issn-type":[{"value":"0009-7330","type":"print"},{"value":"1524-4571","type":"electronic"}],"subject":[],"published":{"date-parts":[[1992,10]]},"assertion":[{"value":"1992-10-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}