Endorfiinit

Endorfiinit are endogenous opioid peptides produced mainly in the brain and in the pituitary gland. They are part of the opioid peptide family and are derived from precursor molecules such as proopiomelanocortin (POMC). The best known member is beta-endorphin, while the broader group includes related peptides such as enkephalins, which contribute to the body’s natural pain-relief system.

Functionally, endorfiinit bind to opioid receptors—mu, delta, and kappa—in the central nervous system and, to a lesser extent, in peripheral tissues. Through these receptors, they modulate pain signaling and can produce analgesia and a sense of well-being. They also act as neuromodulators and neurotransmitters within mood, stress, and reward pathways, influencing autonomic responses and immune interactions.

Release and triggers vary with context. Endorfiinit are released in response to physical stress, tissue injury, and intense exercise, as well as emotional experiences, laughter, and certain therapies such as acupuncture. The experience commonly referred to as a “runner’s high” is often attributed to endorphin release, though other neuromodulatory systems may contribute.

Distribution and action notes indicate that endorfiinit exert their primary effects within the brain. While circulating endorphins can originate from the pituitary, their access to central targets is limited by the blood–brain barrier, making central production important for analgesia and mood regulation.

Clinical and research perspectives view endorfiinit as a natural mechanism for pain control, mood modulation, and stress resilience. They can be influenced by pharmacological opioids, which mimic endogenous effects but carry risks of dependence and side effects. The term endorphin reflects their endogenous, morphine-like actions.