Figure 1. Timeline of apremilast testing on 2-BC alcohol drinking, mechanical allodynia, gene expression, and central amygdala (CeA) electrophysiology assessments.
(A and B) Experimental approach (A) and design of apremilast dose regimen (B) on 2–bottle choice (BC) and von Frey testing across sex and strain. Rats first received 2 weeks of 10% alcohol for 24 hours/day. Starting on week 3, access to alcohol was reduced to 2 hours/day. During week 3–5, apremilast injections (0, 10, and 20 mg/kg; i.p.) was given in 3 cycles separated one week apart in a Latin square design. CeA electrophysiological recordings or isolation for PCR occurred on week 7, while recordings continued through week 8. A subset of rats were tested during late abstinence and received apremilast on week 9. All rats received apremilast injections 1 hour prior to testing on 2-BC, equivalent to 3 hours before von Frey testing on groups examined immediately after alcohol.