Neuronal Nicotinic Acetylcholine Receptors: Novel Targets for CNS Therapeutics / Table 2

Table 2. Comparison of potency and efficacy of nAChR agonists on recombinant human nAChRs expressed on Xenopus Oocytes

Agonist	ha2b2	ha2b4	ha3b2	ha3b4	ha4b2	ha4b4	ha7
ACh
EC₅₀	68.67 mM	82.57 mM	442.90 mM	203.14 mM	68.05 mM	19.68 mM	179.57 mM
I_max	1.25	1.25	5.0	1.25	1.25	1.25	1.25

NIC
EC₅₀	19.23 mM	20.71 mM	132.44 mM	80.30 mM	5.47 mM	5.02 mM	113.34 mM
I_max	0.77 ± 0.11	1.03 ± 0.07	2.84 ± 0.52	0.78 ± 0.05	0.52 ± 0.12	1.0 ± 0.05	1.38 ± 0.11

DMPP
EC₅₀	11.18 mM	22.77 mM	55.87 mM	18.67 mM	17.99 mM	18.71 mM	30.86 mM
I_max	0.53 ± 0.02	0.36 ± 0.02	11.20 ± 1.42	0.98 ± 0.07	0.14 ± 0.05	0.42 ± 0.05	1.02 ± 0.01

CYT
EC₅₀	25.43 mM	38.86 mM	67.09 mM	72.18 mM	2.61 mM	0.90 mM	71.42 mM
I_max	0.13 ± 0.02	0.29 ± 0.08	0.038 ± 0.003	0.60 ± 0.04	0.06 ± 0.01	0.51 ± 0.06	1.16 ± 0.03

^a Potency (EC₅₀) expressed as geometric mean, and efficacy (I_max) are expressed as the arithmetic mean ± S.E.M.

Imax represents the fraction of the ACh ED₈₀ response (EC₂₀ for ha3b2). N = 4-6. Data taken from Chavez-Noriega et al., 1997.

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published 2000