Endurance training changes central and peripheral responses to physostigmine.

Whether the pharmacodynamics of physostigmine (Phy) [rate of decarbamylation of cholinesterase (ChE) enzyme] (Kd) is altered due to acute and/or trained exercise in brain and various tissues of rat has been addressed. Acute exercise (AE) + Phy increased, whereas endurance training (ET) + Phy decreased ChE activity in brain, red blood cells (RBC), and various tissues as compared to Phy alone. The Kd of brain ChE was significantly increased (181% of control) by AE + Phy and decreased (66% of control) by ET + Phy as compared to Phy alone. There was a slight increase (114% of control) in Kd of RBC-ChE in AE + Phy as compared to Phy alone. The Kd of heart ChE was significantly decreased (44% of control) by ET + Phy as compared to Phy alone. The Kd of diaphragm ChE was significantly increased (384% of control) in AE + Phy and decreased (80% of control) in ET + Phy as compared to Phy alone. The Kd of muscle ChE significantly decreased (67% of control) by AE + Phy as compared to Phy alone, but ET + Phy did not affect the Kd in muscle. These results suggested that AE and ET have opposite effects on Kd after Phy administration.