Figure 4.
ICV injection of C8X results in a leftward shift of the acquisition dose response for nicotine, but does not alter NSA after behavior is acquired. In rats that self-administered 3.75 μg/kg, 3 out of 8 acquired with ACSF vs 2 out of 9 acquired with C8X; for the 7.5 μg/kg dose, 10 out of 22 acquired with ACSF vs 21 out of 21 acquired with C8X; and for the 15 μg/kg dose, 6 out of 7 acquired with ACSF vs 7 out of 9 with C8X. Data for 7.5 μg/kg dose was combined from two animal cohorts that produced the same results. In the first cohort, 4 out of 10 animals acquired with ACSF vs 11 out of 11 acquired with C8X and in the second cohort, 6 out of 12 animals acquired ACSF vs 10 out of 10 acquired with C8X. C8X was significantly higher when data was analyzed separately (p<0.05 for each cohort) or together. *p<0.001, C8X vs ACSF.