[Effect of aldosterone and ACTH administration on fluctuation of 5-HT content of the brain and pentobarbital anesthesia in adrenalectomized rats].

The present study was undertaken to determine whether or not adrenalectomy influences anesthesia and increase in brain 5-HT induced by pentobarbital and if such is the case, whether or not aldosterone or ACTH inhibit the effect of adrenalectomy. Male Wistar rats were adrenalectomized or sham-operated and injected with aldosterone (20mug5hg i.p.), ACTH (5.0 mg/kg i.p.) or the vehicle (1.0 ml/kg i.p.) everyday for 1 week after a postoperative interval of 3 days. These rats ware given a normal diet and 1% saline approximately 5% glucose solution. Animals were injected with pentobatbital (50 mg/kg i.p.) 18 hr after the last injection of each hormone. It was found that adrenalectomy enhanced "pentobarbital-anesthesia", although there was no such effect in the adrenalectomized rats pretreated with each hormone. Adrenalectomy inhibited an increase of 5-HT in the brain after pentobarbital, but the hormone pretreatment to those rats did not antagonize the inhibition of the 5-HT increase.