Forskolin and antidiuretic hormone stimulate a Ca2+-activated K+ channel in cultured kidney cells.
Single channels in the apical cell membrane of primary cultured chick kidney cells were studied using the patch clamp technique. Cell-attached recordings revealed the presence of a 107 +/- 6 pS channel that increased fractional open time upon depolarization. Experiments with inside-out excised patches indicated that the channel is K+ selective, Ca2+ activated, and inhibited by Ba2+. The addition of forskolin or antidiuretic hormone (ADH) to the bath during cell-attached recordings caused an increase in the fractional open time of the channel. The activation of a K+ channel by increases in cAMP may be one way in which K+ secretion in the kidney is stimulated by ADH in vivo.
S E
SE
Guggino
B A
BA
Suarez-Isla
W B
WB
Guggino
B
B
Sacktor
D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology*; D001127:Arginine Vasopressin / Q000494:pharmacology*; D002118:Calcium / Q000494:pharmacology*; D002478:Cells, Cultured; D002645:Chickens; D005576:Colforsin; D004224:Diterpenes / Q000494:pharmacology*; D004533:Egtazic Acid / Q000494:pharmacology; D004553:Electric Conductivity / Q000187:drug effects; D007473:Ion Channels / Q000187:drug effects / Q000502:physiology*; D007668:Kidney / Q000166:cytology / Q000502:physiology*; D008564:Membrane Potentials / Q000187:drug effects; D011188:Potassium / Q000378:metabolism*
D000959:Antihypertensive Agents; D004224:Diterpenes; D007473:Ion Channels; D001127:Arginine Vasopressin; D005576:Colforsin; D004533:Egtazic Acid; D011188:Potassium; D002118:Calcium