Tacrine hydrochloride hydrate

A cholinesterase inhibitor that crosses the blood-brain barrier. Tacrine has been used to counter the effects of muscle relaxants, as a respiratory stimulant, and in the treatment of Alzheimer's disease and other central nervous system disorders.(In Vitro):Tacrine hydrochloride (hydrate) (12.5 to 37.5 nM) inhibits venom acetylcholinesterase as well as human serum butyrylcholinesterase in a concentration-dependent manner. The IC50 is 31 nM for snake venom AChE and 25.6 nM for human BChE.(In Vivo):Pretreatment with Tacrine hydrochloride (hydrate) also modifies absolute levels of cocaine self-administration during reacquisition. Body weight declines approximately one-half percent over four days of treatment with intravenous Tacrine hydrochloride (hydrate). Delivery of Tacrine hydrochloride (hydrate) by osmotic pump does not alter either linear- or repeated- cocaine-induced locomotor activity. There is no significant main effect or interaction with Tacrine hydrochloride (hydrate) treatment on active lever responding during reinstatement. Post hoc comparisons indicate that rats self-administering cocaine has significantly lower alkaline phosphatase levels, relative to TTacrine hydrochloride (hydrate)- but not saline- treated rats evaluated by conditioned-place preference.