Which receptor does baclofen act on to decrease muscle spasticity?

Baclofen is a muscle relaxant that specifically targets the gamma-aminobutyric acid B (GABAB) receptor in the central nervous system. This receptor is a type of GABA receptor that plays a critical role in inhibitory neurotransmission. When baclofen binds to GABAB receptors, it leads to hyperpolarization of neurons, which in turn decreases the release of excitatory neurotransmitters. This results in reduced muscle tone and spasticity, making baclofen effective for conditions characterized by muscle spasticity such as multiple sclerosis and spinal cord injuries.

The mechanism of action of baclofen as a GABAB receptor agonist is significant for its clinical applications. By enhancing the inhibitory effects of GABA, baclofen alleviates unwanted spasticity and improves muscle function. This pharmacological action distinguishes baclofen from other potential receptors that could be involved in muscle contraction or relaxation mechanisms.