title: Neuropeptide (calcitonin gene-related peptide) induction of nitric oxide in human keratinocytes in vitro.
abstract: Nitric oxide (NO) is an important signaling molecule in both the central nervous system and the periphery, where it is involved in neurotransmission, vascular and bronchial tone, inflammation, and cutaneous immune function. More recently, NO has been implicated in intracellular signaling and may have a role in cellular differentiation, cytokine expression, and apoptosis. The experiments described herein examined the effect of calcitonin gene-related protein (CGRP), a cutaneous nerve neuropeptide, on NO production in human keratinocytes in vitro. CGRP stimulated two distinct increases in NO production: one within 30 minutes and a second at 24 hours. CGRP stimulated a modest increase in inducible nitric oxide synthase (iNOS) at 3-6 hours. Experimental evidence suggested that CGRP stimulated both constitutive NOS activity and generation of NO via nitrosothiol degradation within the first hour. Production of NO was paralleled by a decrease in nitrosothiol levels for 2 hour, suggesting that immediate NO release may originate from pre-existing stores. Nitrosothiols are ubiquitous molecules that comprise an important NO pool and have intracellular regulatory roles, particularly linked to oxidative stress. The present data indicate that, in addition to its known cAMP signaling pathway, CGRP may act to regulate keratinocyte biology through intracellular NO by modulation of S-nitrosothiol stores and stimulation of NOS activity.
authors.affiliation: Department of Dermatology, State University of New York Medical Center, Brooklyn, USA.
authors.forename: Yaping
authors.initials: Y
authors.lastname: E
authors.forename: Samantha C
authors.initials: SC
authors.lastname: Golden
authors.forename: Alan R
authors.initials: AR
authors.lastname: Shalita
authors.forename: Wei-Li S
authors.initials: WL
authors.lastname: Lee
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Maes
authors.forename: Mary S
authors.initials: MS
authors.lastname: Matsui
mesh_terms: D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism* / Q000494:pharmacology; D002460:Cell Line; D004789:Enzyme Activation / Q000187:drug effects / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D000078404:Epidermal Cells; D006801:Humans; D066298:In Vitro Techniques; D015603:Keratinocytes / Q000166:cytology / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology; D026403:S-Nitrosothiols / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*
chemical_list: D004791:Enzyme Inhibitors; D026403:S-Nitrosothiols; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II; D015740:Calcitonin Gene-Related Peptide