neuropeptide
Quick Summary
Neuropeptides are short chains of amino acids that influence neural activity. They are longer than typical neurotransmitters but shorter than hormones or proteins. Unlike classic neurotransmitters formed near nerve terminals, neuropeptides are assembled in the endoplasmic reticulum and Golgi apparatus before being packaged into vesicles.12
Some neuropeptides are released by neuroendocrine cells in the hypothalamus or pituitary gland and travel through the bloodstream to act on distant sites, functioning as neurohormones. Others are released into the synaptic cleft between neurons in the central nervous system.23
A key characteristic distinguishing neuropeptides from classic neurotransmitters is the duration of their action, which can range from seconds to days, compared to milliseconds for substances like acetylcholine. While released in lower concentrations, neuropeptides are significantly more potent. Examples include substance P, neurotensin, somatostatin, and the opioid peptides like endorphins and enkephalins.23
Ask Britannica AI about this topic
Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.
hypothalamusHypothalamic regulation of hormone secretion…an important group is the neuropeptides. The neuropeptides function not only as neurotransmitters but also as neuromodulators. As neuromodulators, they do not act directly as neurotransmitters but rather increase or decrease the action of neurotransmitters. Well-known examples are the opioids (e.g., enkephalins), so named because they are endogenous (produced in…
Read More…an important group is the neuropeptides. The neuropeptides function not only as neurotransmitters but also as neuromodulators. As neuromodulators, they do not act directly as neurotransmitters but rather increase or decrease the action of neurotransmitters. Well-known examples are the opioids (e.g., enkephalins), so named because they are endogenous (produced in…
Read More
nervous systemNeuroactive peptidesNeuroactive peptides are sequences of amino acids, usually longer than amino acid neurotransmitters yet shorter than hormones or proteins. Unlike the classic neurotransmitters described above, which are formed by enzymes near the presynaptic terminals, neuroactive peptides are assembled by ribosomes attached to the…
Read MoreNeuroactive peptides are sequences of amino acids, usually longer than amino acid neurotransmitters yet shorter than hormones or proteins. Unlike the classic neurotransmitters described above, which are formed by enzymes near the presynaptic terminals, neuroactive peptides are assembled by ribosomes attached to the…
Read More
human nervous systemBasal ganglia…aspiny striatal neurons secrete GABA, neuropeptide Y, somatostatin, or some combination of these. The largest aspiny neurons are evenly distributed neurons that also secrete neurotransmitters and are important in maintaining the balance of dopamine and GABA.
Read More…aspiny striatal neurons secrete GABA, neuropeptide Y, somatostatin, or some combination of these. The largest aspiny neurons are evenly distributed neurons that also secrete neurotransmitters and are important in maintaining the balance of dopamine and GABA.
Read More