Table 5.

Specific cell types of Fos-expressing neuronal ensembles in the pVTA that were activated in the nicotine-induced acceleration of the escalation of alcohol self-administration

Group	GAD67	TH
Air-Naive	17.4 ± 3.9	18.4 ± 1.7
Air-Saline	23.8 ± 10.4	18.4 ± 10.2
Air-Nicotine	35.7 ± 16.1	26.8 ± 4.6
Vapor-Naive	8.6 ± 8.1	2.2 ± 4.6
Vapor-Saline	41.6 ± 20.4	19.32 ± 3.4
Vapor-Nicotine	62.5 ± 6.2	36.4 ± 3.1

These data are represented as the mean ± SEM of double-labeled neurons as a percentage of all Fos-labeled neurons. The total percentage does not necessarily add up to 100%, possibly due to incomplete labeling with cell-type markers.