Table 1.

Composition of nAChR subtypes expressed by DA neurons of dorsal and ventral striatum and ventral midbrain as deduced from immunoprecipitation experiments

nAChR subtype	% of total β2* nAChRs (% of α6* nAChRs)
	Dorsal striatum	Ventral striatum	Ventral midbrain
α4β2	20.5	11.3	29.8
α2α4β2	0	0	8.0
α4α5β2	39.5	53.4	32.2
α4β2β3	6.4	1.1	8.6
α4α6β2β3	29.9 (89.0)	13.7 (40.0)	21.4 (100.0)
α6β2β3	3.7 (11.0)	20.5 (60.0)	0 (0)
α4*	96.3	79.5	100.0
α4 (non-α6)*	66.4	65.8	78.6
α6*	33.6	34.2	21.4