Participation of PKG and PKA-related pathways in the IFN-γ induced modulation of the BKCa channel activity in human cardiac fibroblasts

Cardiomyocytes' prolonged IL‐2 incubation induces enhancement in L‐type Ca2+ channels mediated by inhibitory‐kappaB kinase/nuclear factor‐kappaB signalling

“…The principle of isolation of cardiomyocytes was described in previous works of this research group 5,17 . Briefly, the hearts were attached to the Langendorff apparatus for retrograde perfusion with Ca 2+ ‐free solution containing (in mmol/L) NaCl 120, KCl 5.4, MgSO 4 x7H 2 O 5, Na‐pyruvate 5, glucose 20, taurine 20 and Hepes 10 at a pH of 7.4 adjusted with NaOH.…”

“…The mean cell capacitance was 82 ± 10.4 pF, while the mean input resistance was 10.6 ± 3.4 MΩ. To obtain current densities, the peak currents were normalized by cell capacitance 17 . Half‐maximal effective concentration (logEC 50 ) values for IL‐2‐induced current potentiation were determined by normalizing the current increase with each concentration of IL‐2 to the current increase observed with 10 ng/mL IL‐2.…”

“…The principle of isolation of cardiomyocytes was described in previous works of this research group. 5,17 Briefly, the hearts were attached to the Langendorff apparatus for retrograde perfusion with Ca 2+ -free solution containing (in mmol/L) NaCl 120, KCl 5.4, MgSO 4 x7H 2 O 5, Na-pyruvate 5, glucose 20, taurine 20 and Hepes 10 at a pH of 7.4 adjusted with NaOH. After the initial period of 5-minute perfusion with Ca 2+ -free solution, the hearts were further perfused for about 18-20 minutes with the same solution supplemented with type XIV protease (0.08 mg/mL), type II Worthington collagenase (0.5 mg/mL; 275 U/mg protein) and 20 μmol/L CaCl 2 .…”

“…To obtain current densities, the peak currents were normalized by cell capacitance. 17 Half-maximal effective concentration (logEC 50 ) values for IL-2-induced current potentiation were determined by normalizing the current increase with each concentration of IL-2 to the current increase observed with 10 ng/mL IL-2. When fitting equations to the IL-2 dose-response data (logEC 50 ), the minimum was set at zero and the maximum at 1 (maximal current stimulation) (for details, see Wang et al 2018).…”

Estudo comparativo entre a S-nitroso-N-acetilcisteína e o nitrito de sódio quanto aos seus efeitos hipotensores e alterações bioquímicas vasculares

“…Apesar de evidências que fortalecem a função principal para PKG na regulação da reatividade vascular, a natureza dos mecanismos mediados pela fosforilação dependente de cGMP não são conhecidos em sua totalidade. A ativação da PKG suprime a sua excitação celular devido a abertura dos canais de alta condutância para Ca 2++ e K + voltagem dependente (BKca) (MITROKHIN et al, 2019). Como o MLV expressa diversas classes de canais de K + em densidades distintas, o BKca, pode ser uma proteína essencial para desempenhar ação efetora ativada por vasodilatadores endógenos ou exógenos e podem gerar uma função vasodilatadora em microvasos induzido por NO (CARRIER et al, 1997).…”