MOLECULAR ORGANIZATION OF NEUROTRANSMISSION IN NEUROMUSCULAR SYNAPSES OF SOMATIC MUSCLES IN THE EARTHWORM LUMBRICUS TERRESTRIS

In the somatic muscle of the earthwormLumbricus terrestris, the presence of acetylcholinesterase (AChE) and vesicular ACh transporter (VACHT) enzymes, as well as α1, α2 and β1 subunits of the ionotropic nicotinic ACh channel-receptor complex (nAChR) were detected in the area of motor neuromuscular synapses using fluorescence microscopy. The presence of the mediator acetylcholine (ACh) was demonstrated in the muscle homogenate. Thus, in the evolutionarily primitive somatic musculature of annelids, there is a fully formed cholinergic motor innervation, similar to that found in more highly organized classes of vertebrates, including mammals.