Tolbutamide- and diazoxide-sensitive K+ channel in neurons of substantia nigra pars reticulata.
Single-channel K+ currents were recorded in cell-attached patches from slices of rat substantia nigra. On the somata of neurons in the caudal half of the substantia nigra pars reticulata a K+ selective channel with a unitary conductance of 71 pS (154 mmol/l K+ in pipette filling solution) was identified. The channel was activated both by application of diazoxide (300 mumol/l) and by energy-depleting conditions (200 mumol/l cyanide) and was reversibly blocked by tolbutamide (0.1-1 mmol/l). It is concluded that neurons in the substantia nigra pars reticulata of the rat contain a typical ATP-sensitive K+ channel the activity of which can be modulated by diazoxide and sulfonylureas.
Schwanstecher
C
C
Institut für Pharmakologie und Toxikologie, Universität Göttingen, Germany.
Panten
U
U
D000255:Adenosine Triphosphate / Q000502:physiology; D000818:Animals; D003981:Diazoxide / Q000494:pharmacology*; D005260:Female; D066298:In Vitro Techniques; D008297:Male; D015221:Potassium Channels / Q000187:drug effects*; D051381:Rats; D013378:Substantia Nigra / Q000187:drug effects*; D014044:Tolbutamide / Q000494:pharmacology*
D015221:Potassium Channels; D000255:Adenosine Triphosphate; D014044:Tolbutamide; D003981:Diazoxide