Neuropeptide Y inhibits Ca2+ influx into cultured dorsal root ganglion neurones of the rat via a Y2 receptor

• Published in: British journal of pharmacology 1991-07, Vol.103 (3), p.1781-1789
• Main Authors: Bleakman, D., Colmers, W.F., Fournier, A., Miller, R.J.
• Format: Article
• Language: English
• Subjects: Action Potentials - drug effects; Animals; Animals, Newborn - metabolism; Barium - metabolism; Biological and medical sciences; Calcium - metabolism; calcium currents; Cells, Cultured; Central nervous system; Central neurotransmission. Neuromudulation. Pathways and receptors; current clamp; Electrophysiology; Fundamental and applied biological sciences. Psychology; Fura-2; Ganglia, Spinal - metabolism; Hippocampus - drug effects; Hippocampus - metabolism; intracellular calcium; Ion Channels - metabolism; Neuroeffector Junction - drug effects; Neuroeffector Junction - metabolism; Neurons - metabolism; neuropeptide Y; Neuropeptide Y - pharmacology; neuropeptide Y fragments; Neurotransmitter Agents - metabolism; Peptides - metabolism; Rats; Rats, Inbred Strains; Receptors, Neuropeptide Y; Receptors, Neurotransmitter - metabolism; sensory neurones; Vertebrates: nervous system and sense organs; voltage clamp; Y2 receptor
• ISSN: 0007-1188; 1476-5381
• DOI: 10.1111/j.1476-5381.1991.tb09863.x

1 The identity of the neuropeptide Y (NPY) receptor associated with the observed inhibition of neuronal Ca2+ currents (ICa) in rat dorsal root ganglion (DRG) cells has been established on the basis of agonist responses to analogues and carboxy terminal (C‐terminal) fragments of the NPY molecule. 2 Whole cell barium currents (IBa) in DRG cells were reversibly inhibited by 100 nm NPY, 100 nm PYY and C‐terminal fragments of NPY in a manner that correlated with the length of the NPY fragments (for inhibition of the IBa NPY = PYY > NPY2–36 > NPY13–36 > NPY16–36 > NPY18–36 ≫ NPY25–36). 3 C‐terminal fragments of NPY were also effective in reversibly reducing the ICa, the associated increase in the intracellular Ca2+ concentration ([Ca2+]i) and the increased [Ca2+]i produced by evoked action potentials in the DRG cells. In addition, a Ca2+‐activated Cl− conductance was also reversibly reduced by NPY fragments only when accompanied by a reduction in Ca2+ entry. 4 We conclude that the Y2 receptor for neuropeptide Y is coupled to inhibition of Ca2+ influx via voltage‐sensitive calcium channels in DRG cells.