Umbellulone is a natural product isolated from Umbellularia californica, and stimulates the TRPA1 channel in a subset of peptidergic, nociceptive neurons, activating the trigeminovascular system via this mechanism.
CAY10787 is an oxysterol and a negative allosteric modulator of GABAAreceptors.1,2It reduces GABA-induced currents in HEK cells expressing α1β1γ2or α4β3γ2subunit-containing GABAAreceptors (IC50s = 1.5 and 1 μM, respectively).2CAY10787 (500 nM) reduces GABA-induced depolarization of peptidergic and non-peptidergic nociceptors, C-LTMRs, and cold thermosensors in isolated mouse dorsal root ganglion (DRG) neurons.In vivo, CAY10787 (2, 10, and 50 mg/kg) increases latency to nocifensive behaviors in the hot plate test in mice. 1.Hahn, M., Tang, M., and Subbiah, M.T.Cholest-3,5-dien-7-one formation in peroxidized human plasma as an indicator of lipoprotein cholesterol peroxidation potentialBiochim. Biophys. Acta1255(3)341-343(1995) 2.Niu, C., Leavitt, L.S., Lin, Z., et al.Neuroactive type-A γ-aminobutyric acid receptor allosteric modulator steroids from the hypobranchial gland of marine mollusk, Conus geographusJ. Med. Chem.64(10)7033-7043(2021)
JTP-4819 is a potent and selective prolyl endopeptidase (PEP) inhibitor with potential for treating Alzheimer's disease. At nanomolar concentration, JTP-4819 inhibited the degradation of substance P, arginine-vasopressin, and thyrotropin-releasing hormone by PEP in supernatants of the rat cerebral cortex and hippocampus. Repeated administration of JTP-4819 reversed the aging-induced decrease in brain substance P-like and thyrotropin-releasing hormone-like immunoreactivity, suggesting that this drug may be able to improve the imbalance of peptidergic neuronal systems that develops with senescense by inhibiting PEP activity. JTP-4819 increased acetylcholine release from the frontal cortex and hippocampus, regions closely associated with memory, in both young and aged rats.
Phe-Met-Arg-Phe, amide dose-dependently (ED50=23 nM) activates a K+ current in peptidergic caudodorsal neurons and appears to localize with neuropeptide Y in some brain regions.