The Effects of Exercise on Pharmacokinetics and Pharmacodynamics of Physostigmine in Rats
Abstract
This report describes the effects of a single dose of physostigmine (Phy) on the ability of rats to exercise, effects of prior exercise on acetylcholinesterase (AChE) kinetics, and the effects of exercise training on AChE kinetics. Dose-response studies of Phy and cholinesterase (ChE) inhibition in vivo was carried out. Based on dose-response curves, we selected a dose of 70 ug/kg of Phy, which will inhibit about 30% ChE in red blood cells (RBC). This dose was used for our exercise studies. A comparison of oxygen consumption and heat production in young and adult rats indicated that young rats attained a higher VO2 max than the adult rats did. The younger rats showed a higher resting heat capacity than the adult rats did. Different intensities of acute exercise produced a significant inhibition of ChE activity in heart and in diaphragm without significantly affecting brain and thigh muscle. However, acute exercise produced a slight increase in RBC ChE activity. Phy inhibited ChE in RBC and in all the tissues studied. Phy followed by acute exercise further increased the ChE inhibition in TBC and brain without affecting heart, diaphragm or thigh muscle. Phy administration followed by acute exercise resulted in a significant decrease in lactate and pyruvate concentration. Phy combined with acute exercise decreased the increase in hemoglobin induced by exercise alone. Phy (70 ug/kg, i.m.) increased the endurance time of rats weighing 160-200 g. Keywords: Cholinesterase inhibitors; Organofluorophosphates; Physotigmine; ChE activity; Acute exercise; Training; VO2 max; Respiratory exchange ratio; Heat production; Lactate hemoglobin; Pyruvate; Hematocrit; RA 5.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 15, 1989
- Accession Number
- ADA211896
Entities
People
- Arman Ur Rashid
- S. N. Dube
- S. R. Babu
- Satu M. Somani
- Vince Garcia
Organizations
- Southern Illinois University School of Medicine