Kallidin

Part of speech: noun

Definitions

1. A biologically active peptide involved in inflammatory and cardiovascular responses, promoting vasodilation and increasing vascular permeability; a component derived from kininogens that mediates pain and swelling in tissues; a molecule playing a key role in regulating blood pressure and electrolyte balance through its action on specific receptors
2. A peptide formed from precursor proteins that contributes to the widening of blood vessels and facilitates fluid movement into tissues during inflammation; a chemical agent triggering nociceptive pathways and promoting sensations of pain; an endogenous compound that helps control circulatory system functions by interacting with cellular receptors
3. A short protein fragment generated during inflammatory processes that causes blood vessels to expand and become more permeable; a mediator of pain signals in the nervous system; an important regulator of cardiovascular and renal activity through receptor activation mechanisms

Etymology: Kallidin takes its name from kallikrein, an enzyme named after the Greek "kallikreas," meaning "of the pancreas," because it was first found in that organ. Kallikrein releases kallidin from a larger blood protein, so the name points to the enzyme that produces the peptide rather than to what the peptide does. The rest of the name is built on "kinin," a family label from Greek "kinein," "to move," which reflects these peptides' ability to make smooth muscle contract and tissues swell. Kallidin is essentially bradykinin with an extra lysine residue at its front end, so its name records a family resemblance more than a separate discovery story.

Synonyms: vasoactive peptide