In the previous experiments, we began testing of alcohol consumption one week after LPS injection. In the next experiment we asked if the increased drinking would be seen if we waited for one month. LPS was administered to B6 males (one injection) and B6 females (two injections) and one month after the last LPS administration mice were tested in a two-bottle choice paradigm. The increase of alcohol intake was still present in the LPS pre-treated group in male mice (Fig. 5A), and this increased consumption was sustained after one week of alcohol deprivation (Fig. 5B). In contrast, no differences in alcohol consumption between saline and LPS-pretreated groups were found in B6 female mice (Fig. 5C and D). Thus, LPS increases alcohol consumption in both male and female mice, but the male mice appear more vulnerable (require only a single injection, females require two treatments) and the effect is more persistent in males than females. Complete data for ethanol intake (amount of ethanol consumed, preference for ethanol and total fluid intake) in a two-bottle choice test for B6 inbred mice of both sexes are presented in Supplemental Figs. 8 and 9 (for detailed statistics see Supplementary materials in Supplemental Table 4).
