Effects of Neostigmine and Physostigmine on Activity of Na+,K+-ATPase in Various Subdivisions of Rat Brain

Resumo

The effects of intramuscular administration of neostigmine and physostigmine on Na⁺,K⁺-ATPase activity in various cerebral subdivisions were examined in rats. In CNS and peripheral tissues, both agents rapidly and significantly reduced activity of cholinesterases by 30-50%. The development of intoxication did not change the marker indices of stress reaction. In the cerebral cortex, physostigmine increased Na⁺,K⁺-ATPase activity, whereas neostigmine suppressed it. In addition, neostigmine decreased activity of this enzyme in the cerebellum. In contrast, both agents produced no effects on Na⁺,K⁺-ATPase activity in the striatum. The data corroborate the view on functional interaction between Na⁺,K⁺-ATPase and nicotinic cholinoreceptors in rat cerebral cortex.