Immunofluorescent Identification of GABAergic Structures in the Somatic Muscle of the Earthworm Lumbricus terrestris

-Using the immunofluorescence confocal microscopy, we detected the following GABAergic structures in the somatic muscle of the body wall of the earthworm: neurotransmitter gamma-aminobutyric acid (GABA); the enzyme responsible for synthesis of GABA, glutamate decarboxylase; type 1, 2, and 3 membrane transporters of GABA providing its reuptake; pre- and postsynaptic type A (ionotropic) and type B (metabotropic) GABA receptors. These structures are localized in the areas of cholinergic neuromuscular synapses. We assume that GABA can participate in modulation of motor activity of the earthworm somatic muscles both at pre- and postsynaptic levels of cholinergic neuromuscular synapses.