. Author manuscript; available in PMC: 2009 Apr 1.

Published in final edited form as: Psychopharmacology (Berl). 2008 May 26;200(2):205–215. doi: 10.1007/s00213-008-1195-7

Table 1.

Acquisition of lever-pressing responses

	Group 1 (water/METH)		Group 2 (METH only)		Group 3 (sucrose only)
	NVHL	Sham	NVHL	Sham	NVHL	Sham
Water or sucrose
Days to criterion	1.5±0.5^*	3.2±3.2	n/a	n/a	1.0±0	1.0±0
Number of presses	1415±866	1626±694	n/a	n/a	476±26	470±26
Methamphetamine
Days to criterion	1.3±0.8	1.7±1.3	1.0±0^**	3.5±1.2	n/a	n/a
Number of presses	215±86^*	158±64	180±58	133±48	n/a	n/a
Latency (min) to 100 presses (criterion)	563±207^*	721±154	561±196^**	869±93	n/a	n/a
n per group^a	20	19	8	8	9	7

All values are mean±standard deviation (SD).

METH: methamphetamine, NVHL: neonatal ventral hippocampal lesion

One NVHL rat from group 2 was recatheterized during self-administration acquisition; data from this rat was not included in the analysis of acquisition.

p<0.05,

^**

p<0.01 vs. sham; independent t tests