Which neurochemical is released in the spinal cord by acupuncture, affecting Laminae II?

The neurochemical that is released in the spinal cord by acupuncture and affects Lamina II is enkephalin. Enkephalins are a type of endogenous opioid peptide that play a significant role in regulating pain and contribute to the analgesic effects of acupuncture. They bind to opioid receptors in the central nervous system, particularly in the spinal cord, which is part of the pathway that modulates pain transmission.

Lamina II, also known as the substantia gelatinosa, is a specific area in the spinal cord where the processing of nociceptive (pain-related) signals occurs. When acupuncture is performed, it is believed that the stimulation of certain points can promote the release of enkephalins in this region, leading to an increased inhibition of pain signaling. This mechanism underlies the pain-relieving effects often associated with acupuncture and illustrates how traditional practices can interact with neurophysiological pathways in the body.

In contrast, while beta-endorphin is another opioid peptide that is involved in pain modulation, it primarily has a more systemic effect rather than being localized primarily to the spinal cord's Lamina II. Alpha-endorphin is less commonly discussed in this context, and serotonin, while it has important roles in mood and pain modulation