Abstract
Influence of gasotransmitters carbon monoxide (CO) and hydrogen sulfide (H 2 S) on the electrical and contractile activities of smooth muscle cells (SMCs) of the guinea pig ureter and rat aorta were studied by methods of double sucrose bridge and mechanography. It has been shown that CO causes a dose-dependent decrease of the contractile response of SMCs of the ureter and rat aorta and also reduces the amplitude and duration of the action potential plateau. Against the background of the action of biologically active substances, agonists α1-adrenergetic and H1-histaminergetic receptors (phenylephrine and histamine, respectively), these effects of CO donor (CORM II) were amplified. The inhibitory effect of CO on the parameters of the contractile and electrical activities of smooth muscles is attenuated by blocking potassium channels of plasma membrane with tetraethylammonium (TEA) or inhibition of soluble guanylate cyclase (ODQ [1H-[1,2,4]-oxadiazolo[4,3-a]quinoxalin-l-one]). Thus, the effects of carbon monoxide on the electrical and contractile activities of SMCs are associated with an increase potassium conductivity of the membrane or the activation of soluble guanylate cyclase. In experiments with a donor of hydrogen sulfide (NaHS), it was shown, that it has an activating effect on the electrical and contractile activities of smooth muscles of the guinea pig ureter, which is caused by the action of potassium conductivity of the membrane. Activating effect of H 2 S on the contractile properties of SMCs of the guinea pig ureter decreased by blocking ATP-dependent channels with glibenclamide. Analysis of the effect of H 2 S on sodium and calcium conductance of the membrane smooth muscles of the ureter using modified sodium-free and TEA- containing Krebs solution showed that the contribution of potassium conductance is mainly sold at high concentrations (100 and 1000 μmol) donor NaHS. Probably, that the impact of low concentrations of NaHS (10 μmol) on the amplitude of contractions SMCs of the ureter and performed through the activation of the calcium component of the action potential. It was shown, that activating effect of NaHS determined by involving sodium-dependent ion transporters to cAMP-dependent inhibition of potassium conductance membranes of smooth muscles.
Highlights
Influence of gasotransmitters carbon monoxide (CO) and hydrogen sulfide (H2S) on the electrical and contractile activities of smooth muscle cells (SMCs) of the guinea pig ureter and rat aorta were studied by methods of double sucrose bridge and mechanography
It has been shown that CO causes a dosedependent decrease of the contractile response of SMCs of the ureter and rat aorta and reduces the amplitude and duration of the action potential plateau
Наук, профессор кафедры биофизики и функциональной диагностики СибГМУ
Summary
РОЛЬ ГАЗОВЫХ ПОСРЕДНИКОВ В РЕГУЛЯЦИИ ФУНКЦИЙ ГЛАДКИХ МЫШЦ: ВЕРОЯТНЫЕ ЭФФЕКТОРНЫЕ СИСТЕМЫ. Методами двойного сахарозного моста и механографии были изучены механизмы влияния газовых посредников: монооксида углерода (СО) и сероводорода (H2S) на электрическую и сократительную активность гладкомышечных клеток (ГМК) морской свинки и аорты крысы. Можно утверждать, что оказываемое монооксидом углерода влияние на электрическую и сократительную активность ГМК связано с повышением калиевой проводимости мембраны и (или) активацией растворимой гуанилатциклазы. В экспериментах с донатором сероводорода (NaHS) было показано, что он оказывает активирующее действие на электрическую и сократительную активность гладких мышц мочеточника, которое обусловлено влиянием на калиевую проводимость мембраны ГМК. Анализ влияния сероводорода на натриевую и (или) кальциевую проводимость мембраны ГМК мочеточника с помощью модифицированных безнатриевых и ТЭА-содержащих растворов Кребса показал, что вклад калиевой проводимости мембраны ГМК в основном реализуется при больших концентрациях (100 и 1000 мкмоль) донора NaHS. Другие исследователи считают такое утверждение преждевременным, указывая либо на отсутствие связи между повышением концентрации газов и их релаксирующим действием, либо на противоположные по направленности констрикторные эффекты [10]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
