Ethyl alcohol on escape from electrical periaqueductal gray stimulation in rats.

In a procedure to measure the escape latency and threshold for aversive electrical stimulation of the Peri-Aqueductal Gray (PAG) the effect of ethyl alcohol was tested in order to validate aversive PAG stimulation further as a model for testing potential anxiolytics. Doses of 0.2-1.6 g/kg were given orally in an ascending sequence and were found to increase escape latency and threshold. A second dose of 0.8 g/kg had no effect, suggesting development of tolerance. Spontaneous activity in the test environment was not changed by alcohol. These results indicate specific effects of alcohol on aversive stimulation and reinforce the suggestion to use this phenomenon as a model for human anxiety.