Voltage-Gated Calcium-Modulated Potassium Channels of Large Unitary Conductance: Structure, Diversity, and Pharmacology

摘要: Calcium-sensitive and voltage-dependent channels of large unitary conductance (BKca) are found ubiquitously distributed in different cells tissues where they participate regulating many cellular processes (Latorre et al. 1989). Because cytosolic Ca2+activates BKcachannels play an important role coupling chemical to electrical signaling. In neurons contribute action potential repolarization (e.g., Sah 1996) presynaptic terminals appear modulate transmitter release (Robitaille 1993; Knaus 1996; Yazejian 1997; but see Warbington 1996). present abundantly virtually all types smooth muscle crucial controlling tone (Anwer Brayden Nelson 1992; 1995; for reviews Quayle Sanders 1992). These also control fluid secretion (Peterson 1986) reabsorption (Guggino 1987). chick cochleae variants the BKcachannel may help determine characteristic frequency each hair cell helping establish tonotopic map (Dhasakumar Rosenblatt Ramanathan 1999). were cloned fromDrosophilataking advantage existence mutant slowpoke (Slo)in which this potassium current is absent (Elkins 1986; Gho Mallard 1986). The primary sequence theSlo protein showed that