The Influence of Some ~ Min 9 Acids on Neuro - Muscular Transmission

Normally, skeletal muscles contract when receiving impulses from the nerve centres along the motor nerve fibres and the neuro-muscular junction. Acetylcholine is considered to be the chemical mediator involved in these functions. The neuro-muscular junction appears to be highly susceptible to the influence of chemicals of divergent nature and other biological substances present in the body. While plausible explanations are available for the mode of action of certain drugs, with others, these rem ain still unsolved. Choline and acetylcholine in large doses block the transmission (Rosenbleuth and Simeone, 1938). Curariform drugs desensitize the end plate to acetylcholine [Robson and Keele, 1950); procaine has a similar curariform effect (Tobias, 1959); magnesium ions induce neuro-muscular block and adrenaline can temporarily relieve this block (Dybing, 1957). Adrenaline also modifies the effect of acetylcholine at the neuro-muscular junction (Burn, 1945) . Prostigmine, eserine and adrenaline potentiate the contractions produced by nerve stimulation of isolated organs. Some antibiotics, protein in nature also exert an inhibitory effect on the transmission of nerve impulses at the lunction (Sirsi, 1960 unpublished observations).