TABLE 1.

Pharmacological parameters calculated from concatemeric α3β4* nAChR and from α3β4α5 nAChR expressed from loose subunits

Oocytes injected with RNA encoding either concatenated α3β4* nAChR or single α3, β4, and α5 subunits in a 1:1:1 ratio were perfused with the nAChR agonists acetylcholine (10⁻⁶ to 10⁻² m), cytisine (10^−6.25 to 10⁻³ m), nicotine (10^−6.5 to 10^−3.5 m), or the nAChR antagonist mecamylamine (10^−7.5 to 10⁻⁴ m). Data are presented as the mean ± S.E., with numbers of individual oocytes tested (n) as indicated. * denotes concatemeric constructs.

Expressed nAChR	Acetylcholine			Cytisine			Nicotine			Mecamylamine
	n	Log EC50	nH ± S.E.	n	Log EC50	nH ± S.E.	n	Log EC50	nH ± S.E.	n	Log IC50	nH ± S.E.
β4α3β4α3β4*	16	−3.9 ± 0.02	1.8 ± 0.11	6	−4.8 ± 0.07	1.6 ± 0.4	6	−4.2 ± 0.07	1.6 ± 0.4	6	−7.4 ± 0.04	−0.9 ± 0.05
β4α3β4α3α3*	11	−4.0 ± 0.03	1.4 ± 0.13	6	−4.7 ± 0.04	1.2 ± 0.12	6	−4.1 ± 0.07	1.8 ± 0.4	6	−6.7 ± 0.03	−1.1 ± 0.08
β4α3β4α3α5(Asp-398)*	17	−4.0 ± 0.01	1.6 ± 0.06	10	−4.8 ± 0.04	1.3 ± 0.15	8	−4.2 ± 0.05	1.8 ± 0.4	8	−6.2 ± 0.03	−1.1 ± 0.08
β4α3β4α3α5(Asn-398)*	17	−4.0 ± 0.02	1.6 ± 0.09	10	−4.8 ± 0.03	1.3 ± 0.13	8	−4.3 ± 0.06	1.9 ± 0.4	8	−6.0 ± 0.03	−1.2 ± 0.08
α3β4α5 (1:1:1)	6	−3.8 ± 0.02	1.6 ± 0.10	6	−4.7 ± 0.03	1.5 ± 0.2	6	−4.4 ± 0.03	2.0 ± 0.2	6	−6.4 ± 0.02	−1.5 ± 0.09