These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Pharmacological characterisation of the relaxation induced by the soluble guanylate cyclase activator, BAY 60-2770 in rabbit corpus cavernosum.
    Author: Estancial CS, Rodrigues RL, De Nucci G, Antunes E, Mónica FZ.
    Journal: BJU Int; 2015 Oct; 116(4):657-64. PubMed ID: 25715977.
    Abstract:
    OBJECTIVE: To characterise the relaxation induced by the soluble guanylate cyclase (sGC) activator, BAY 60-2770 (4-({(4-carboxybutyl) [2- (5-fluoro-2-{[4'-(trifluoromethyl) biphenyl-4-yl]methoxy}phenyl)ethyl] amino}methyl)benzoic acid) in rabbit corpus cavernosum (CC). MATERIAL AND METHODS: The penis from male New Zealand rabbits was removed and fours strips of CC were obtained. Concentration-response curves to BAY 60-2770 were constructed in the absence and presence of inhibitors of nitric oxide synthase, N (G)-nitro-L- arginine methyl ester (L-NAME, 100 μm), sGC, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, 10 μm) and phosphodiesterase type 5 (PDE-5), tadalafil (0.1 μm). The potency (pEC50 ) and maximal response (Emax ) values were determined. Then, electrical-field stimulation (EFS)-induced contraction or relaxation was tested in the absence and presence of BAY 60-2770 (0.1 or 1 μm) alone or combined with ODQ (10 μm). For EFS-induced relaxation two protocols were used: (i) ODQ (10 μm) was first incubated for 20 min and then BAY 60-2770 (1 μm) was added for another 20 min (ODQ + BAY 60-2770); (ii) in different CC strips, BAY 60-2770 was incubated for 20 min followed by another 20 min with ODQ (BAY 60-2770 + ODQ). The intracellular levels of cyclic guanosine monophosphate (cGMP) were also determined. RESULTS: BAY 60-2770 potently relaxed rabbit CC with mean (sem) pEC50 and Emax values of 7.58 (0.19) and 81 (4)%, respectively. The inhibitors ODQ (n = 7) or tadalafil (n = 7) produced 4.2- and 6.3-leftward shifts, respectively in BAY 60-2770-induced relaxation without interfering with the Emax values. The intracellular levels of cGMP were augmented after stimulation with BAY 60-2770 (1 μm) alone, whereas its co-incubation with ODQ produced even higher levels of cGMP. The EFS-induced contraction was reduced in the presence of BAY 60-2770 (1 μm) and this inhibition was even greater when BAY 60-2770 was co-incubated with ODQ. The nitrergic stimulation induced CC relaxation, which was abolished in the presence of ODQ. BAY 60-2770 alone increased the amplitude of relaxation. Co-incubation of ODQ and BAY 60-2770 did not alter the relaxation in comparison with ODQ alone. Interestingly, when BAY 60-2770 was incubated before ODQ, EFS-induced relaxation was partly restored in comparison with ODQ alone or ODQ + BAY 60-2770. CONCLUSIONS: The relaxation induced by the sGC activator, BAY 60-2770 was increased after sGC oxidation and unaltered in the absence of nitric oxide. Thus, this class of substances may have advantages over sGC stimulators or PDE-5 inhibitors for treating patients with erectile dysfunction and extensive endothelial damage.
    [Abstract] [Full Text] [Related] [New Search]