Parasite-specific gamma-aminobutyric acid (GABA)-gated chloride channel (GABACl (context-dependent, not universal))

Parasite-specific gamma-aminobutyric acid (GABA)-gated chloride channels are ligand-gated ion channels unique to invertebrate parasites, belonging to the cys-loop superfamily. Upon binding GABA, they open a chloride ion conductance pathway, hyperpolarizing neurons or muscle, and inhibiting excitation. These channels are essential for parasite neuromuscular function and are key targets for a wide range of antiparasitic drugs, including piperazine and macrocyclic lactones, which cause paralysis and death of the parasite by overactivating or modulating these channels[1][3]. Their absence in mammals and other vertebrates allows for selective targeting, making them crucial for controlling nematode (roundworm), arthropod, and other invertebrate parasitic diseases[1][3][4]. If you require information on a specific parasite species' channel (e.g., C. elegans, H. contortus, L. salmonis), further detail and nomenclature can be refined[5][3].

Other names

GABA-gated chloride channelParasitic GABA receptor chloride channelInvertebrate GABAClGABA receptor (invertebrate) chloride channel

Agonism (direct activators): Drugs such as piperazine act as agonists to cause channel opening, hyperpolarizing parasite muscle and causing flaccid paralysis[1]. Positive allosteric modulation and activation: Macrocyclic lactones bind to and keep channels open, leading to potentiation or direct activation of chloride influx and paralysis[4]. Antagonism (blockers): Compounds like fipronil and dieldrin block chloride influx, leading to overstimulation/convulsions and death in target arthropods[3].