Peptide Database

BK · Kallidin precursor fragment

Bradykinin is a 9-amino-acid vasoactive peptide of the kinin-kallikrein system. It produces vasodilation, increased vascular permeability, pain, and inflammation by acting on B1 and B2 receptors. ACE inhibitors (a major drug class) lower blood pressure partly by preventing bradykinin degradation. Icatibant, a B2 antagonist, is approved for hereditary angioedema. Research also implicates bradykinin in COVID-19 pathology (bradykinin storm hypothesis).

GAL

Galanin is a 29-30 amino acid neuropeptide widely distributed throughout the CNS and peripheral nervous system. It modulates memory, mood, pain, seizures, appetite, and sleep via three receptor subtypes (GALR1–3). Research focuses on its roles in Alzheimer's disease (galanin hyperinnervation of cholinergic neurons), depression, epilepsy, and eating behavior. Both agonists and antagonists have therapeutic potential depending on the target condition.

SP · NK1 ligand

Substance P is an 11-amino-acid neuropeptide of the tachykinin family and a primary neurotransmitter of pain signaling in the spinal cord. It binds NK1 receptors to mediate neurogenic inflammation, pain hypersensitivity, and emotional processing. NK1 antagonists have been developed for pain, depression (aprepitant), and nausea. Research also implicates substance P in wound healing, immune activation, and neuroinflammation.