EFFECT OF ETHANOL ON CORTICAL SPREADING DEPRESSION

The effects of intragastric ethanol (3 g kg(-1) day(-1) in a total vol ume of 3.8 ml/kg, for 7 days) on cortical spreading depression (SD) we re studied in adult Wistar rats (N = 10). Control animals (N = 8) rece ived an equivalent volume of distilled water for the same period of ti me. SD was elicited by stimulation of one point of the right frontal c ortex with 2% KCl for 1 min at 20-min intervals and was recorded for 6 h at two points on the parietal surface of the same hemisphere. The e thanol group failed to gain weight during treatment, while the mean we ight of the control group increased by 17 g. Rats treated with ethanol displayed higher mean SD velocities (range: 3.87 +/- 0.54 to 4.58 +/- 0.76 mm/min) than the control animals (range: 2.99 +/- 0.30 to 3.78 /- 0.46 mm/min), the difference being significant until the fourth h o f recording. The results indicate that ethanol intake for 7 days incre ases the susceptibility of the cerebral cortex to SD in adult rats.