What neurotransmitter is known for its involvement in signaling pain and inflammatory responses?

Substance P is a neuropeptide that plays a crucial role in the transmission of pain signals and mediates inflammatory responses in the nervous system. When tissue is damaged or inflamed, Substance P is released from neurons and activates pain receptors, which contribute to the sensation of pain. It is especially involved in the response to noxious stimuli, helping the body signal that something is wrong.

In addition to its role in pain perception, Substance P is also associated with the process of inflammation, promoting the release of prostaglandins and other inflammatory mediators that enhance the pain response. This makes it a significant player in the complex pathways of nociception and inflammation.

Other neurotransmitters listed, such as GABA, dopamine, and acetylcholine, have different primary functions. GABA is primarily an inhibitory neurotransmitter involved in reducing neuronal excitability, dopamine is associated with reward and motivation pathways, and acetylcholine primarily facilitates muscle contraction and autonomic functions. Thus, none of these alternatives are directly involved in signaling pain or inflammatory responses like Substance P.