The effects of cholinolytic drugs and cholinesterase blockade on deprivation based activity and appetitive behavior

The effects of scopolamine HBr (0.125-1.0 mg/kg), methscopolamine bromide (0.125-1.0 mg/kg), physostigmine sulphate (0.05-0.4 mg/kg), and neostigmine bromide (0.025-0.2 mg/kg) were studied under different states of deprivation. The behavioral measures included spontaneous wheel activity, food consumption and water intake. The effects of both cholinolytics were effective in reducing the level of spontaneous activity and the amount of food eaten under all dose levels regardless of the deprivation condition. The level of water intake was differentially affected by the locus of action of the cholinolytics. Wheel activity was also decreased under both acetylcholinesterase (AChE) inhibitors with the extent of the reduction significantly affected by the deprivation condition of the subjects. Acetylcholinesterase reduction reduced food intake and increased the level of water intake with the deprivation state differentiating the magnitude of the effects for physostigmine vs neostigmine. The results were taken as evidence for the cholinergic modulation, at the central and peripheral level, of consummatory behaviors and activity. It was concluded that the effects of cholinolytics and AChE inhibitors are largely the result of peripheral cholinergic receptor site changes in the use of available acetylcholine.