Abstract
It was reported that there was a remarkable difference in the effects of pentobarbital (1) or hexobarbital (2) between adult female and male rats and that there was a sex difference in the metabolism of these drugs (1, 2). However, most works on the effects of barbiturates had been done with either male or female animals only. Moreover, the reports on the sex difference of the effects of barbiturates were principally concerned with the single injection of drug.
The authors have reported that the sex difference was observed in the effects of some hormones on the growth and development of rats and the enzyme activity in the rat's liver (3-5).
The purpose of the present -study was to compare the effects in male and female rats of continued daily injection of pentobarbital as well as phenobarbital. The development of the tolerance to drugs and the existence of sex difference in drug effects were observed.
