Electroacupuncture inhibits CB1 upregulation induced by ethanol withdrawal in mice

CB1R play a role in alcohol withdrawal and in some effects of acupuncture. Interestingly, acupuncture has been used to alleviate alcohol withdrawal. Here, we investigated electroacupuncture (EA) effects during ethanol withdrawal on CB1R immunoreactivity. Male Swiss mice were daily injected with ethanol (2g/kg, i.p) (EtOH group), for 21 days. EA was performed daily during 4 days of ethanol withdrawal. The stimuli of 2 or 100 Hz were provided in two acupoints combination: Ea1 [(ST-36/Zusanli) and (PC-6/Neiguan)] or Ea2 [(DU-14/Dazhui) and (DU-20/Baihui)]. The specificity of the acupoints were assessed by the inclusion of three additional groups, Ea3 [(ST 25/Tianshu - acupoints used to other non-related disorders)], Sham1 and Sham2 (transdermic stimulation nearly to the respective acupoints). EtOH group were only handled during withdrawal and Saline group was chronically treated with Saline and handled similarly to EtOH group. One day after withdrawal the animals were perfused and their brains processed for immunohistochemistry. There was an increase of CB1R in the prefrontal cortex, striatum, hippocampus, amygdala and ventral tegmental area. The procedures used in the 2HzEa1 and 100HzEa2 groups were the most effective and specific to inhibit this CB1R upregulation. Therefore, EA inhibits CB1R upregulation seen in ethanol withdrawn mice. The specificity of acupoints stimulation depends of the encephalic nuclei, acupoints association and frequency of stimulation.