Involvement of amygdaloid neuropeptide Y in the anxiolytic effects of acupuncture during ethanol withdrawal in rats

- Acupuncture at HT7 inhibited the ethanol withdrawal-induced decrease of NPY protein level in the CeA.
- Acupuncture at HT7 reversed the ethanol withdrawal-induced reduction of NPY mRNA level in the CeA.
- Acupuncture at HT7 normalized the ethanol withdrawal-induced reduced ratio of p-CREB/CREB in the CeA.
- The anxiolytic effect of acupuncture was blocked by the intra-CeA infusion of BIBP 3226.
- The anxiolytic effect of acupuncture was not blocked by the intra-CeA infusion of BIIE 0246.

The role of neuropeptide Y (NPY) in the central nucleus of amygdala (CeA) in the preventive effects of acupuncture against ethanol withdrawal-induced anxiety was investigated. Rats were treated with 3 g/kg/day of ethanol for 28 days, followed by 3 days of withdrawal. Bilateral acupuncture treatment at HT7 (Shen-Men), PC6 (Nei-Guan) or a non-acupoint was respectively added to the rats during the withdrawal once a day for three days. Enzyme-linked immunosorbent assays and real-time polymerase chain reaction analyses showed there was a significant decrease in NPY protein and mRNA expression in the CeA during ethanol withdrawal, which was reversed by acupuncture at HT7 but neither at PC6 nor at a non-acupoint. Acupuncture at HT7 also greatly inhibited the decrease in cAMP response element-binding protein (CREB) phosphorylation in the CeA. In elevated plus maze tests, a selective NPY Y1 receptor antagonist BIBP 3226 into the CeA before the acupuncture abolished almost completely the anxiolytic effect of acupuncture at HT7. These results suggest that acupuncture at HT7 rescues the depletion of amygdaloid NPY and reverses the decrease in CREB phosphorylation to produce anxiolytic effects during ethanol withdrawal.