Person: Martínez Sainz, María Del Pilar
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First Name
María Del Pilar
Last Name
Martínez Sainz
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Veterinaria
Department
Anatomía y Embriología
Area
Anatomía y Anatomía Patológica Comparadas
Identifiers
15 results
Search Results
Now showing 1 - 10 of 15
Item Powerful Relaxation of Phosphodiesterase Type 4 Inhibitor Rolipram in the Pig and Human Bladder Neck(The Journal of Sexual Medicine, 2014) Fernandes Ribeiro, Ana Sofía; Fernandes, Vítor S.; Martínez Sáenz, Ana; Martínez Sainz, María Del Pilar; Barahona Gomáriz, María Victoria; Orensanz Muñoz, Luis Miguel; Blaha, Igor; Serrano Margüello, Daniel; Bustamante, Salvador; Carballido, Joaquín; García Sacristán, Albino; Prieto Ocejo, Dolores; Hernández Rodríguez, Medardo VicenteIntroduction: Phosphodiesterase type 5 (PDE5) inhibitors act as effective drugs for the treatment of lower urinary tract symptom (LUTS). There is a poor information, however, about the role of the PDE4 inhibitors on the bladder outflow region contractility. Aim: To investigate PDE4 expression and the relaxation induced by the PDE4 inhibitor rolipram versus that induced by the PDE5 blockers sildenafil and vardenafil, in the pig and human bladder neck. Methods: Immunohistochemistry for PDE4 expression, myographs for isometric force recordings and fura-2 fluorescence for simultaneous measurements of intracellular Ca2+ concentration ([Ca2+]i ) and tension for rolipram in bladder neck samples were used. Main outcome measures: PDE4 expression and relaxations to PDE4 and PDE5 inhibitors and simultaneous measurements of [Ca2+]i and tension. Results: PDE4 expression was observed widely distributed in the smooth muscle layer of the pig and human bladder neck. On urothelium-denuded phenylephrine (PhE)-precontracted strips of pig and human, rolipram, sildenafil and vardenafil produced concentration-dependent relaxations with the following order of potency: rolipram> > sildenafil>vardenafil. In pig, the adenylyl cyclase activator forskolin potentiated rolipram-elicited relaxation, whereas protein kinase A (PKA) blockade reduced such effect. On potassium-enriched physiological saline solution (KPSS)-precontracted strips, rolipram evoked a lower relaxation than that obtained on PhE-stimulated preparations. Inhibition of large (BKCa ) and intermediate (IKCa ) conductance Ca2+ -activated K+ channels, neuronal voltage-gated Ca2+ channels, nitric oxide (NO) and hydrogen sulfide (H2 S) synthases reduced rolipram responses. Rolipram inhibited the contractions induced by PhE without reducing the PhE-evoked [Ca2+]i increase. Conclusions: PDE4 is present in the pig and human bladder neck smooth muscle, where rolipram exerts a much more potent relaxation than that elicited by PDE5 inhibitors. In pig, rolipram-induced response is produced through the PKA pathway involving BKCa and IKCa channel activation and [Ca2+]i desensitization-dependent mechanisms, this relaxation also being due to neuronal NO and H2S release.Item Role of Calcitonin Gene-Related Peptide in Inhibitory Neurotransmission to the Pig Bladder Neck(2011) Martínez-Sáenz, Ana ; Recio Visedo, María Paz; Orensanz, Luis M. ; Leite Fernandes, Vitor Samuel; Martínez Sainz, María Del Pilar; Bustamante, Salvador ; Carballido, Joaquín ; García-Sacristán, Albino ; Prieto Ocejo, Dolores; Hernández Rodríguez, Medardo VicentePurpose: We studied the role of calcitonin gene-related peptide in nonadrenergic, noncholinergic neurotransmission to the pig bladder neck. Materials and Methods: We used immunohistochemical techniques to determine the distribution of calcitonin gene-related peptide immunoreactive fibers as well as organ baths for isometric force recording. We investigated relaxation due to endogenously released or exogenously applied calcitonin gene-related peptide in urothelium denuded phenylephrine precontracted strips treated with guanethidine, atropine and NG-nitro-L-arginine to block noradrenergic neurotransmission, muscarinic receptors and nitric oxide synthase, respectively. Results: Rich calcitonin gene-related peptide immunoreactive innervation was found penetrating through the adventitia and distributed in the suburothelial and muscle layers. Numerous, variable size, varicose calcitonin gene-related peptide immunopositive terminals were seen close below the urothelium. In the muscle layer calcitonin gene-related peptide immunopositive nerves usually appeared as varicose terminals running along muscle fibers. Electrical field stimulation (2 to 16 Hz) and exogenous calcitonin gene-related peptide (0.1 nM to 0.3 μM) evoked frequency and concentration dependent relaxation, respectively. Nerve responses were potentiated by capsaicin, decreased by calcitonin gene-related peptide (8–37) and abolished by tetrodotoxin, capsaicin sensitive primary afferent blockers, calcitonin gene-related peptide receptors and neuronal voltage gated Na+ channels. Calcitonin gene-related peptide-induced relaxation was potentiated by the neuronal voltage gated Ca2+ channels blocker ω-conotoxin-GVIA and decreased by calcitonin gene-related peptide (8–37). Calcitonin gene-related peptide relaxation was not modified by blockade of endopeptidases, nitric oxide synthase, guanylyl cyclase and cyclooxygenase. Conclusions: Results suggest that calcitonin gene-related peptide is involved in the nonadrenergic, noncholinergic inhibitory neurotransmission of the pig bladder neck, producing relaxation through neuronal and muscle calcitonin gene-related peptide receptors. Nitric oxide/cyclic guanosine monophosphate and cyclooxygenase pathways do not seem to be involved in such responses.Item COX-2 is involved in vascular oxidative stress and endothelial dysfunction of renal interlobar arteries from obese Zucker rats(Free Radical Biology and Medicine, 2015) Muñoz Picos, Mercedes; Sánchez Pina, Ana Alejandra; Martínez Sainz, María Del Pilar; Benedito Castellote, Sara; López-Oliva Muñoz, María Elvira; García Sacristán, Albino; Hernández Rodríguez, Medardo Vicente; Prieto Ocejo, DoloresObesity is related to vascular dysfunction through inflammation and oxidative stress and it has been identified as a risk factor for chronic renal disease. In the present study, we assessed the specific relationships among reactive oxygen species (ROS), cyclooxygenase2 (COX-2), and endothelial dysfunction in renal interlobar arteries from a genetic model of obesity/insulin resistance, the obese Zucker rats (OZR). Relaxations to acetylcholine(ACh) were significantly reduced in renal arteries from OZR compared to their counterpart, the lean Zucker rat (LZR), suggesting endothelial dysfunction. Blockade of COX with indomethacin and with the selective blocker of COX-2 restored the relaxations to ACh in obese rats. Selective blockade of the TXA2/PGH2 (TP) receptor enhanced ACh relaxations only in OZR, while inhibition of the prostacyclin (PGI2) receptor (IP) enhanced basal tone and inhibited ACh vasodilator responses only in LZR. Basal production of superoxide was increased in arteries of OZR and involved NADPH and xanthine oxidase activation and NOS uncoupling. Under conditions of NOS blockade, ACh induced vasoconstriction and increased ROS generation that were augmented in arteries from OZRandbluntedbyCOX-2 inhibition and by the ROS scavenger tempol. Hydrogen peroxide (H2O2) evoked both endothelium-and vascular smooth muscle (VSM)-dependent contractions, as well as ROS generation that was reduced by COX-2 inhibition.In addition, COX-2 expression was enhanced in both VSM and endothelium of renal arteries from OZR. These results suggest that increased COX-2-dependent vasoconstriction contributes to renal endothelial dysfunction through enhanced (ROS) generation in obesity.COX-2 activity is in turn upregulated by ROS.Item Mechanisms involved in the nitric oxide-induced vasorelaxation in porcine prostatic small arteries(Naunyn Schmiedebergs Arch Pharmacol, 2011) Fernandes, Vítor S.; Martínez Sáenz, Ana; Recio Visedo, María Paz; Fernandes Ribeiro, Ana Sofía; Ana Sánchez; Martínez Sainz, María Del Pilar; Martínez Gómez, Ana Cristina; García Sacristán, Albino; Orensanz Muñoz, Luis Miguel; Prieto Ocejo, Dolores; Hernández Rodríguez, Medardo VicenteBenign prostatic hypertrophy has been known to be related with glandular ischemia processes, and nitric oxide (NO) is a potent vasodilator agent. Therefore, the current study investigates the mechanisms underlying the NO-induced vasorelaxation in pig prostatic small arteries. In microvascular myographs, relaxation to electrical field stimulation (EFS), or to exogenous (S)-nitroso-N-acetylpenicillamine (SNAP) and acetylcholine (ACh), was observed on noradrenaline-precontracted prostatic small arterial rings under non-adrenergic and non-cholinergic (NANC) conditions. EFS (1-16 Hz) and exogenous SNAP (0.1-30 μM) evoked frequency- and concentration-dependent relaxation, respectively. Tetrodotoxin, a neuronal voltage-gated Na(+) channel blocker, abolished the EFS-evoked relaxation. ACh (1 nM-10 μM) induced concentration-dependent relaxation, which was reduced by the NO synthase inhibitor N(G)-nitro-L: -arginine (L: -NOARG). L: -NOARG also reduced the EFS-elicited relaxation but failed to modify the response to SNAP. 1H-[1,2,4]-oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) and iberiotoxin (IbTX), blockers of soluble guanylyl cyclase and large conductance Ca(2+)-activated K(+) (BK(Ca)) channels, respectively, reduced EFS-, SNAP-, and ACh-induced relaxation. The combination of ODQ with IbTX did not produce further inhibition of the responses to either SNAP or ACh, compared with ODQ alone. Blockade of cyclooxygenases and intermediate and small conductance Ca(2+)-activated, ATP-dependent, and voltage-gated K(+) channels did not change the EFS and SNAP responses. In conclusion, our results suggest that NO and non-NO non-prostanoid factor(s) derived from NANC nerves are involved in the vasodilatation of pig prostatic small arteries. NO produces relaxation through soluble guanylyl cyclase activation-dependent BK(Ca) channel opening and through guanylyl cyclase-independent mechanisms. The vasodilatation elicited by NO could be useful to prevent prostatic ischemia.Item Noradrenergic vasoconstriction of pig prostatic small arteries(Naunyn-Schmiedeberg’s Arch Pharmacol, 2008) Recio Visedo, María Paz; Orensanz Muñoz, Luis Miguel; Martínez Sainz, María Del Pilar; Navarro Dorado, Jorge; Bustamante Alarma, Salvador; García Sacristán, Albino; Prieto Ocejo, Dolores; Hernández Rodríguez, Medardo VicenteThe current study investigated the distribution of adrenergic nerves and the action induced by noradrenaline (NA) in pig prostatic small arteries. Noradrenergic innervation was visualized using an antibody against dopamine-beta-hydroxylase (DBH), and the NA effect was studied in small arterial rings mounted in microvascular myographs for isometric force recordings. DBH-immunoreactive nerve fibers were located at the adventitia and the adventitia-media border of the vascular wall. Electrical field stimulation (EFS, 1-32 Hz) evoked frequency-dependent contractions that were reduced by guanethidine and prazosin (adrenergic neurotransmission and α1-adrenoceptors blockers, respectively) and by the α2-adrenoceptor agonist UK 14,304. The α2-adrenoceptor antagonist rauwolscine reversed the UK 14,304-produced inhibition. NA produced endothelium-independent contractions that were antagonized with low estimated affinities and Schild slopes different from unity by prazosin and the α1A-adrenoceptor antagonist N-[2-(2-cyclopropylmethoxyphenoxy) ethyl]-5-chloro-α-α-dimethyl-1H-indole-3-ethanamine (RS 17053). The α1A-adrenoceptor antagonist 5-methyl-3-[3-[4-[2-(2,2,2,-trifluoroethoxy) phenyl]-1-piperazinyl]propyl]-2,4-(1H)-pyrimidinedione (RS 100329), which also displays high affinity for α1L-adrenoceptors, and the α1L-adrenoceptor antagonist tamsulosin, which also has high affinity for α1A- and α1D-adrenoceptors, induced rightward shifts with high affinity of the contraction-response curve to NA. The α1D-adrenoceptor antagonist 8-[2-[4-(2-methoxyphenyl)-1-piperazinyl]-ethyl]8-azaspiro[4,5]decane-7,9-dione dihydrochloride (BMY 7378) failed to modify the NA contractions that were inhibited by extracellular Ca2+ removal and by voltage-activated (L-type) Ca2+ channel blockade. These data suggest that pig prostatic resistance arteries have a rich noradrenergic innervation; and NA, whose release is modulated by prejunctional α2-adrenoceptors, evokes contraction mainly through activation of muscle α1L-adrenoceptors coupled to extracellular Ca2+ entry via voltage (L-type)- and non-voltage-activated Ca2+ channels.Item Neuronal and non-neuronal bradykinin receptors are involved in the contraction and/or relaxation to the pig bladder neck smooth muscle(Neurourology and urodynamics, 2013) Ribeiro, Ana Sofía Fernandes; Leite Fernandes, Vitor Samuel; Martínez Sainz, María Del Pilar; Martínez-Sáenz, Ana; Pazos Rodríguez, María Ruth; Orensanz Muñoz, Luis Miguel; Recio Visedo, María Paz; Bustamante Alarma, Salvador; Carballido Rodríguez, Joaquín; García Sacristán, Albino; Prieto Ocejo, Dolores; Hernández Rodríguez, Medardo VicenteAims: The current study investigates the role played by bradykinin (BK) receptors in the contractility to the pig bladder neck smooth muscle. Methods: Bladder neck strips were mounted in myographs for isometric force recordings and BK receptors expression was also determined by immunohistochemistry. Results: B2 receptor expression was observed in the muscular layer and urothelium whereas B1 expression was consistent detected in urothelium. A strong B2 immunoreactivity was also observed within nerve fibers among smooth muscle bundles. On urothelium-denuded preparations basal tone, BK induced concentration-dependent contractions which were reduced in urothelium-intact samples, by extracellular Ca(2+) removal and by blockade of B2 receptors and voltage-gated Ca(2+) (VOC) and non-VOC channels, and increased by cyclooxygenase (COX) inhibition. On phenylephrine-precontracted denuded strips, under non-adrenergic non-cholinergic (NANC) conditions, electrical field stimulation-elicited frequency-dependent relaxations which were reduced by B2 receptor blockade. In urothelium-intact samples, the B1 receptor agonist kallidin promoted concentration-dependent relaxations which were reduced by blockade of B1 receptors, COX, COX-1 and large-conductance Ca(2+) -activated K(+) (BKCa ) channels and abolished in urothelium-denuded samples and in K(+) -enriched physiological saline solution-precontracted strips. Conclusions: These results suggest that BK produces contraction of pig bladder neck via smooth muscle B2 receptors coupled to extracellular Ca(2+) entry via VOC and non-VOC channels with a minor role for intracellular Ca(2+) mobilization. Facilitatory neuronal B2 receptors modulating NANC inhibitory neurotransmission and urothelial B1 receptors producing relaxation via the COX-1 pathway and BKCa channel opening are also demonstrated.Item Role of endogenous hydrogen sulfide in nerve-evoked relaxation of pig terminal bronchioles(Pulmonary Pharmacology & Therapeutics, 2016) Fernandes, Vítor S.; Recio Visedo, María Paz; López-Oliva Muñoz, María Elvira; Martínez Sainz, María Del Pilar; Fernandes Ribeiro, Ana Sofía; Barahona Gomáriz, María Victoria; Martínez Gómez, Ana Cristina; Benedito Castellote, Sara; Agis Torres, Ángel; Cabañero, Alberto; Muñoz, Gemma M.; García Sacristán, Albino; Orensanz Muñoz, Luis Miguel; Hernández Rodríguez, Medardo VicenteHydrogen sulfide (H2S) is a gasotransmitter employed for intra- and inter-cellular communication in almost all organ systems. This study investigates the role of endogenous H2S in nerve-evoked relaxation of pig terminal bronchioles with 260 μm medium internal lumen diameter. High expression of the H2S synthesis enzyme cystathionine γ-lyase (CSE) in the bronchiolar muscle layer and strong CSE-immunoreactivity within nerve fibers distributed along smooth muscle bundles were observed. Further, endogenous H2S generated in bronchiolar membranes was reduced by CSE inhibition. In contrast, cystathionine β-synthase expression, another H2S synthesis enzyme, however was not consistently detected in the bronchiolar smooth muscle layer. Electrical field stimulation (EFS) and the H2S donor P-(4-methoxyphenyl)-P-4-morpholinylphosphinodithioic acid (GYY4137) evoked smooth muscle relaxation. Inhibition of CSE, nitric oxide (NO) synthase, soluble guanylyl cyclase (sGC) and of ATP-dependent K+, transient receptor potential A1 (TRPA1) and transient receptor potential vanilloid 1 (TRPV1) channels reduced the EFS relaxation but failed to modify the GYY4137 response. Raising extracellular K+ concentration inhibited the GYY4137 relaxation. Large conductance Ca2+-activated K+ channel blockade reduced both EFS and GYY4137 responses. GYY4137 inhibited the contractions induced by histamine and reduced to a lesser extent the histamine-induced increases in intracellular [Ca2+]. These results suggest that relaxation induced by EFS in the pig terminal bronchioles partly involves the H2S/CSE pathway. H2S response is produced via NO/sGC-independent mechanisms involving K+ channels and intracellular Ca2+ desensitization-dependent pathways. Thus, based on our current results H2S donors might be useful as bronchodilator agents for the treatment of lung diseases with persistent airflow limitation, such as asthma and chronic obstructive lung disease.Item The bitter taste receptor (TAS2R) agonist denatonium promotes a strong relaxation of rat corpus cavernosum(Biochemical Pharmacology, 2023) Navarro Dorado, Jorge; Climent Flórez, Belén; López-Oliva Muñoz, María Elvira; Martínez Sainz, María Del Pilar; Hernández Martín, Marina; Agis Torres, Ángel; Recio Visedo, María Paz; Barahona Gomáriz, María Victoria; Benedito Castellote, Sara; Leite Fernandes, Vitor Samuel; Hernández Rodríguez, Medardo VicenteBitter taste receptors (TAS2R) are found in numerous extra-oral tissues, including smooth muscle (SM) cells in both vascular and visceral tissues. Upon activation, TAS2R stimulate the relaxation of the SM. Nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signaling pathway is involved in penile erection, and type 5 phosphodiesterase (PDE5) inhibitors, a cGMP-specific hydrolase are used as first-line treatments for erectile dysfunction (ED). Nevertheless, PDE5 inhibitors are ineffective in a considerable number of patients, prompting research into alternative pharmacological targets for ED. Since TAS2R agonists regulate SM contractility, this study investigates the role of TAS2Rs in rat corpus cavernosum (CC). We performed immunohistochemistry to detect TAS2R10, isometric force recordings for TAS2R agonists denatonium and chloroquine, the slow-release H2S donor GYY 4137, the NO donor SNAP, the β-adrenoceptor agonist isoproterenol and electrical field stimulation (EFS), as well as measurement of endogenous hydrogen sulfide (H2S) production. The immunofluorescence staining indicated that TAS2R10 was broadly expressed in the CC SM and to some extent in the nerve fibers. Denatonium, chloroquine, SNAP, and isoproterenol cause potent dose-dependent SM relaxations. H2S production was decreased by NO and H2S synthase inhibitors, while it was enhanced by denatonium. In addition, denatonium increased the relaxations induced by GYY 4137 and SNAP but failed to modify EFS- and isoproterenol-induced responses. These results suggest neuronal and SM TAS2R10 expression in the rat CC, where denatonium induces a strong SM relaxation per se and promotes the H2S- and NO-mediated inhibitory gaseous neurotransmission. Thus, TAS2R10 might represent a valuable therapeutic target in ED.Item In vitro inhibition of phosphodiesterase type 4 enhances rat corpus cavernosum nerve-mediated relaxation induced by gasotransmitters(Life Sciences, 2022) Leite Fernandes, Vitor Samuel; López-Oliva Muñoz, María Elvira; Martínez Sainz, María Del Pilar; Agis Torres, Ángel; Recio Visedo, María Paz; Navarro Dorado, Jorge; Barahona Gomáriz, María Victoria; Benedito Castellote, Sara; Prieto Ocejo, Dolores; Climent Flórez, Belén; Hernández Rodríguez, Medardo VicenteAims: Nitric oxide (NO) and hydrogen sulfide (H2S) are involved in nerve-mediated corpus cavernosum (CC) relaxation. Expression of phosphodiesterase type 5 (PDE5) and type 4 (PDE4), cyclic guanosine monophosphate (cGMP)- and cyclic adenosine monophosphate (cAMP)-specific, respectively, has been described and PDE5- and PDE4-inhibitors induce cavernous smooth muscle relaxation. Whereas the NO/cGMP signaling pathway is well established in penile erection, the cAMP-mediated mechanism is not fully elucidated. The aim of this study is to investigate the localization and the functional significance of PDE4 in rat CC tone regulation. Main methods: We performed immunohistochemistry for the detection of the PDE4A isoenzyme. Isometric tension recordings for roflumilast and tadalafil, PDE4 and PDE5 inhibitors, respectively, electrical field stimulation (EFS) and β-adrenoceptor agonist isoproterenol and endogenous H2S production measurement. Key findings: A marked PDE4A expression was detected mainly localized in the nerve cells of the cavernous smooth muscle. Furthermore, roflumilast and tadalafil exhibited strong corpus cavernous relaxations. Endoge-nous H2S production was decreased by NO and H2S synthase inhibitors and increased by roflumilast. Isopro-terenol- and EFS-induced relaxations were increased by roflumilast. Significance: These results indicate that PDE4A is mainly expressed within the nerves cells of the rat CC, where roflumilast induces a potent corpus cavernous relaxation per se and potentiates the response induced by β-adrenoceptor activation. The fact that roflumilast enhances H2S production, as well as EFS-elicited responses suggests that PDE4 inhibitors modulate, in a positive feedback fashion, nerve-mediated relaxation induced by gasotransmitters, thus indicating a key role for neuronal PDE4 in penile erection.Item Hydrogen Sulfide Plays a Key Role in the Inhibitory Neurotransmission to the Pig Intravesical Ureter(Plos One, 2014) Fernandes, Vítor S.; Fernandes Ribeiro, Ana Sofía; Martínez Sainz, María Del Pilar; López-Oliva Muñoz, María Elvira; Barahona Gomáriz, María Victoria; Orensanz Muñoz, Luis Miguel; Martínez Sáenz, Ana; Recio Visedo, María Paz; Benedito Castellote, Sara; Bustamante, Salvador; García Sacristán, Albino; Prieto Ocejo, Dolores; Hernández Rodríguez, Medardo Vicente; Agustin Guerrero-HernandezAccording 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.