Because neuronal released endogenous H2S has a key role in relaxation of the bladder outflow region, we investigated the mechanisms involved in H2S dependent inhibitory neurotransmission to the pig bladder neck. Bladder neck strips were mounted in myographs for isometric force recording and simultaneous measurement of intracellular Ca(2+) and tension. On phenylephrine contracted preparations electrical field stimulation and the H2S donor GYY4137 evoked frequency and concentration dependent relaxation, which was reduced by desensitizing capsaicin sensitive primary afferents with capsaicin, and the blockade of adenosine 5'-triphosphate dependent K(+) channels, cyclooxygenase and cyclooxygenase-1 with glibenclamide, indomethacin and SC560, respectively. Inhibition of vanilloid, transient receptor potential A1, transient receptor potential vanilloid 1, vasoactive intestinal peptide/pituitary adenylyl cyclase-activating polypeptide and calcitonin gene-related peptide receptors with capsazepine, HC030031, AMG9810, PACAP6-38 and CGRP8-37, respectively, also decreased electrical field stimulation and GYY4137 responses. H2S relaxation was not changed by guanylyl cyclase, protein kinase A, or Ca(2+) activated or voltage gated K(+) channel inhibitors. GYY4137 inhibited the contractions induced by phenylephrine and by K(+) enriched (80 mM) physiological saline solution. To a lesser extent it decreased the phenylephrine and K(+) induced increases in intracellular Ca(2+). H2S produces pig bladder neck relaxation via activation of adenosine 5'-triphosphate dependent K(+) channel and by smooth muscle intracellular Ca(2+) desensitization dependent mechanisms. H2S also promotes the release of sensory neuropeptides and cyclooxygenase-1 pathway derived prostanoids from capsaicin sensitive primary afferents via transient receptor potential A1, transient receptor potential vanilloid 1 and/or related ion channel activation.

Along history, music has been used in a variety of ways for therapeutic purposes and has long been recognized for its physiological and psychological effects. Music listening can be an effective nursing intervention, to enhance relaxation, provide distraction, and reduce pain. The aims of this study were to identify changes produced by different musical stimuli in blood pressure (BP), heart rate (HR), respiratory rate (RR), and oxygen saturations (SpO2) and to verify the influence of music listening on patients' facial expressions with severe cerebral damage. A quasiexperimental study was performed in 26 patients with severe cerebral damage, divided into control and case groups. Patients belonging to the case group were exposed to musical stimuli, radio, classical relaxing music (CRM), and relaxing music with nature sounds (RMNS). Patients were evaluated by measuring vital signs before and after exposure to each musical stimulus, as were the patients within the control group. Patients in the control group were exempt from any musical stimulus. Facial expressions were observed in each patient within the case group during the intervention. The results show that radio produced a slight increase in systolic BP, HR, RR, and SpO2. The CRM induced a decrease of RR and an increase of SpO2 and also produced alterations of the facial expression. When RMNS was played, a decrease was displayed in BP, HR, and RR and an increase was displayed in SpO2. Alterations in facial expression were displayed in each patient. The results of the study suggest that the application of musical stimuli such as CRM and RMNS can be used to provide a state of relaxation in patients with severe cerebral damage.

We investigated the possible involvement of H2S in nitric oxide independent inhibitory neurotransmission to the pig bladder neck. We used immunohistochemistry to determine the expression of the H2S synthesis enzymes cystathionine γ-lyase and cystathionine β-synthase. We also used electrical field stimulation and myographs for isometric force recordings to study relaxation in response to endogenously released or exogenously applied H2S in urothelium denuded, phenylephrine precontracted bladder neck strips under noradrenergic, noncholinergic, nonnitrergic conditions. Cystathionine γ-lyase and cystathionine β-synthase expression was observed in nerve fibers in the smooth muscle layer. Cystathionine γ-lyase and cystathionine β-synthase immunoreactive fibers were also identified around the small arteries supplying the bladder neck. Electrical field stimulation (2 to 16 Hz) evoked frequency dependent relaxation, which was decreased by DL-propargylglycine and abolished by tetrodotoxin (blockers of cystathionine γ-lyase and neuronal voltage gated Na(+) channels, respectively). The cystathionine β-synthase inhibitor O-(carboxymethyl)hydroxylamine did not change nerve mediated responses. The H2S donor GYY4137 (0.1 nM to 10 μM) induced potent, concentration dependent relaxation, which was not modified by neuronal voltage gated Na(+) channels, or cystathionine γ-lyase or cystathionine β-synthase blockade. Results suggest that endogenous H2S synthesized by cystathionine γ-lyase and released from intramural nerves acts as a powerful signaling molecule in nitric oxide independent inhibitory transmission to the pig bladder neck.

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 N^G-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⁺ (K_ATP) 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, PACAP_6–38 and CGRP_8–37, 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 K_ATP 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.