title: Hydrogen sulfide plays a key role in the inhibitory neurotransmission to the pig intravesical ureter.
abstract: According to previous observations nitric oxide (NO), as well as an unknown nature mediator are involved in the inhibitory neurotransmission to the intravesical ureter. This study investigates the hydrogen sulfide (H2S) role in the neurogenic relaxation of the pig intravesical ureter. We have performed western blot and immunohistochemistry to study the expression of the H2S synthesis enzymes cystathionine γ-lyase (CSE) and cystathionine β-synthase (CBS), measurement of enzymatic production of H2S and myographic studies for isometric force recording. Immunohistochemical assays showed a high CSE expression in the intravesical ureter muscular layer, as well as a strong CSE-immunoreactivity within nerve fibres distributed along smooth muscle bundles. CBS expression, however, was not consistently observed. On ureteral strips precontracted with thromboxane A2 analogue U46619, electrical field stimulation (EFS) and the H2S donor P-(4-methoxyphenyl)-P-4-morpholinylphosphinodithioic acid (GYY4137) evoked frequency- and concentration-dependent relaxations. CSE inhibition with DL-propargylglycine (PPG) reduced EFS-elicited responses and a combined blockade of both CSE and NO synthase (NOS) with, respectively, PPG and NG-nitro-L-arginine (L-NOARG), greatly reduced such relaxations. Endogenous H2S production rate was reduced by PPG, rescued by addition of GYY4137 and was not changed by L-NOARG. EFS and GYY4137 relaxations were also reduced by capsaicin-sensitive primary afferents (CSPA) desensitization with capsaicin and blockade of ATP-dependent K+ (KATP) channels, transient receptor potential A1 (TRPA1), transient receptor potential vanilloid 1 (TRPV1), vasoactive intestinal peptide/pituitary adenylyl cyclase-activating polypeptide (VIP/PACAP) and calcitonin gene-related peptide (CGRP) receptors with glibenclamide, HC030031, AMG9810, PACAP6-38 and CGRP8-37, respectively. These results suggest that H2S, synthesized by CSE, is involved in the inhibitory neurotransmission to the pig intravesical ureter, through an NO-independent pathway, producing smooth muscle relaxation via KATP channel activation. H2S also promotes the release of inhibitory neuropeptides, as PACAP 38 and/or CGRP from CSPA through TRPA1, TRPV1 and related ion channel activation.
authors.affiliation: Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Vítor S
authors.initials: VS
authors.lastname: Fernandes
authors.affiliation: Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Ana S F
authors.initials: AS
authors.lastname: Ribeiro
authors.affiliation: Departamento de Anatomía y Anatomía Patológica Comparadas, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Pilar
authors.initials: P
authors.lastname: Martínez
authors.affiliation: Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: María Elvira
authors.initials: ME
authors.lastname: López-Oliva
authors.affiliation: Departamento de Toxicología y Farmacología, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: María Victoria
authors.initials: MV
authors.lastname: Barahona
authors.affiliation: Departamento de Investigación, Hospital Universitario Ramón y Cajal, Madrid, Spain.
authors.forename: Luis M
authors.initials: LM
authors.lastname: Orensanz
authors.affiliation: Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Martínez-Sáenz
authors.affiliation: Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Paz
authors.initials: P
authors.lastname: Recio
authors.affiliation: Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: Benedito
authors.affiliation: Departamento de Urología, Hospital Universitario Puerta de Hierro-Majadahonda, Madrid, Spain.
authors.forename: Salvador
authors.initials: S
authors.lastname: Bustamante
authors.affiliation: Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Albino
authors.initials: A
authors.lastname: García-Sacristán
authors.affiliation: Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Dolores
authors.initials: D
authors.lastname: Prieto
authors.affiliation: Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Medardo
authors.initials: M
authors.lastname: Hernández
mesh_terms: D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid / Q000494:pharmacology; D000818:Animals; D003541:Cystathionine beta-Synthase / Q000378:metabolism; D003542:Cystathionine gamma-Lyase / Q000378:metabolism; D005260:Female; D006862:Hydrogen Sulfide / Q000378:metabolism*; D008297:Male; D009025:Morpholines / Q000494:pharmacology; D009130:Muscle, Smooth / Q000201:enzymology; D009479:Neuropeptides / Q000378:metabolism; D009946:Organothiophosphorus Compounds / Q000494:pharmacology; D013552:Swine; D009435:Synaptic Transmission / Q000187:drug effects; D014513:Ureter / Q000166:cytology / Q000201:enzymology*; D014662:Vasoconstrictor Agents / Q000494:pharmacology
chemical_list: C529376:GYY 4137; D009025:Morpholines; D009479:Neuropeptides; D009946:Organothiophosphorus Compounds; D014662:Vasoconstrictor Agents; D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; D003541:Cystathionine beta-Synthase; D003542:Cystathionine gamma-Lyase; D006862:Hydrogen Sulfide