Abstract
In brain of adult and developing rats the Na+-K+-adenosine triphosphatase (Na+-K+-ATPase) system seems to react to serotonin (5-MT) changes induced pharmacologically. A 5-HT agonist (quipazine) elicits a response of the enzyme activity in the cerebral cortex in vivo, which is neutralized with a 5-HT antagonist (methysergide). This effect was observed from day 21 to adulthood. Also in a state of 5-HT receptor hypersensitivity (rats treated early with 5,6-dihydroxytryptamine), the response of Na+-K+-ATPase to the 5-HT agonist was higher than without neurotoxic lesion of 5-HT paths. These data suggest involvement of the Na+-K+-ATPase system in 5-HT receptor sensitivity in the rat brain.