Inhibitory Effects of Inhaled Methyl Methacrylate Vapor on Amphibian Skeletal Muscle

The effect of inhaled vapors of methyl methacrylate (MMA) at a 2000 ppm concentration was studied on electrically stimulated in situ amphibian skeletal muscle preparations. Upon exposure to the vapor for 30 min, there was a significant fall in maximal twitch tension, a depression in elicited responses to a train of tetanizing stimuli and an upward and rightward shift in the strength-duration curve. Responses during a 30-minute post-exposure recovery period seldom reached sham control values.