CGP 55845 hydrochloride is primarily utilized in neuroscience research as a selective antagonist for GABA_B receptors. It is instrumental in studying the role of these receptors in the central nervous system, particularly in modulating neurotransmitter release and neuronal excitability. Researchers employ it to investigate conditions like epilepsy, anxiety, and depression, where GABA_B receptor activity plays a significant role. Additionally, it is used in electrophysiological studies to understand synaptic plasticity and the mechanisms underlying learning and memory. Its application extends to exploring potential therapeutic targets for neurological and psychiatric disorders.