In experiments on white rats there were investigated features of antidromic bioelectric activity of presynaptic efferent endings of neuromuscular synapses of white rats in conditions of system action of prozerin and 4-aminopyridine (4-AP). It is revealed, that introduction of both prozerin and 4-AP results in occurrence of antidromic activity in efferent nervous fibres which character is close to the action of these substances. Possible mechanisms of this activity occurrence are discussed.
