Table 2. Native K_ATP channels in visceral and vascular smooth muscles (RT-PCR analysis).

	Transcript
Smooth muscle	Kir6.1	Kir6.2	SUR1	SUR2B	Subunit composition	Conductance (140 mm K+)	Reference
Murine colon	−	+	−	+	Kir6.2–SUR2B	27 pS	Koh et al. 1998
Guinea-pig stomach	+	+	−	+	Kir6.1–SUR2B	37 pS	Sim et al. 2002
Pig urethra	+	+	+	+	Kir6.1–6.2–SUR1	43 pS	Teramoto et al. 1997b
					Kir6.1–6.2–SUR2B		Teramoto et al. 2000
							Yunoki et al. 2002
Cultured human	+	−	−	+	Kir6.1–SUR2B	28 pS	Cui et al. 2002