Pattern of alcohol administration and physical dependence.

The purpose of this work was to study the influence of the pattern of alcohol administration on the intensity of withdrawal syndrome. Some rats were intoxicated by inhalation of ethanol vapor. The ethanol concentration in atmosphere was increased throughout the whole experiment in such a manner that the blood alcohol concentration (BAC) during the experiment increased as a linear function of time. When the area under BAC curve was varied by changing the duration of alcohol administration and keeping constant the slope of BAC increase, the intensity of withdrawal syndrome increased with the duration of alcohol intoxication. When the duration of alcohol administration and the slopes of the BAC curves were varied in such a manner that the area under the BAC curves was kept constant, the severity of the withdrawal syndrome increased with the slope of the BAC curves.