Fig. 2
From: Role of GABA pathway in motor and non-motor symptoms in Parkinson's disease: a bidirectional circuit
GABA and GABA receptors: glutamate is converted to GABA by the enzyme glutamic acid decarboxylase, which is then stored in the specialized vesicles. The GABA is released upon presynaptic activation of GABAergic neurons, which activates Cl- ion entrance through activation of GABA receptors, leading to hyperpolarization and inhibition of the postsynaptic membrane. Excess GABA in the synaptic cleft is reuptake through GABA transporter to the presynaptic neurons