leucineenkefalin

Leucine enkephalin, also known as Leu-enkephalin, is a naturally occurring opioid peptide found in the mammalian brain and spinal cord. It is one of the two forms of enkephalin, the other being methionine enkephalin. These peptides are endogenous ligands, meaning they bind to and activate opioid receptors within the body.

Leucine enkephalin is synthesized from a precursor protein called proenkephalin. Its primary role is as a neurotransmitter or neuromodulator, influencing a range of physiological processes. It is particularly involved in pain perception, where it acts to inhibit the transmission of pain signals. Beyond pain, leucine enkephalin also plays a role in mood regulation, stress response, and gastrointestinal function.

The peptide is released from neurons and binds to opioid receptors, primarily the mu-opioid receptor and the delta-opioid receptor. This binding initiates a cascade of intracellular events that ultimately lead to changes in neuronal activity. The effects of leucine enkephalin are generally short-lived due to its rapid degradation by enzymes in the body. Its discovery and the subsequent understanding of enkephalins have been crucial in the development of pain management strategies and the study of the endogenous opioid system.