Central muscarinic effects of physostigmine on mood, cardiovascular function, pituitary and adrenal neuroendocrine release.

The mechanism by which physostigmine exerts its behavioral, neuroendocrine and cardiovascular effects was explored in two separate experiments. In the first, the centrally-acting cholinesterase inhibitor physostigmine was compared with the non-centrally-acting agent neostigmine. In contrast to physostigmine, neostigmine caused no effects. In the second experiment, pretreatment with scopolamine, in contrast to methscopolamine, attenuated physostigmine's effects. The results suggest that physostigmine exerts its effects via a central muscarinic mechanism.