The role of potassium channels and calcium in the relaxation mechanism of magnesium sulfate on the isolated rat uterus
2019
Аутори:
Sokolović, DraganaDrakul, Dragana
Oreščanin Dušić, Zorana
Tatalović, Nikola
Pecelj, Milica
Milovanović, Slobodan
Blagojević, Duško
Тип документа:
Чланак у часопису (Објављена верзија)
Метаподаци
Приказ свих података о документуАпстракт:
MgSO4 is used as a tocolytic agent. It is considered to be a calcium channel antagonist, but a different mechanism of its action might be involved. The aim of this study was to examine the contribution of calcium concentrations and potassium channels in the mechanism of MgSO4-mediated uterine relaxation. Isolated uteri from female Wister rats were treated with increasing MgSO4 concentrations (0.1-30 mM). MgSO4 induced dose-dependent inhibition of spontaneous activity. Addition of Ca2+ (6 mM and 12 mM) stimulated uterine contractile activity and attenuated the inhibitory activity of MgSO4. In order to analyze the role of different subtypes of potassium channels, Ca2+-stimulated uteri were pretreated with glibenclamide (Glib), a selective ATP-sensitive potassium channel inhibitor (KATP), tetraethylammonium (TEA), a non-specific inhibitor of large conductance calcium-activated potassium channels (BKCa), and 4-aminopyridine (4-AP), a voltage-sensitive potassium channel inhibitor (Kv), at concentrations that had no effect per se. Pretreatment with 4-AP had no effect on MgSO4-mediated relaxation of Ca2+-stimulated uteri. The relaxing effect of MgSO4 was potentiated by pretreatment with glibenclamide. Pretreatment with TEA attenuated the MgSO4-mediated decrease in frequency. Our results suggest that MgSO4 acts as a general calcium antagonist that influences Ca2+-mediated potassium channels. Furthermore, it seems that MgSO4 uterine relaxation activity is partially mediated by selective ATP-sensitive potassium channels, suggesting an ATP-dependent role.
Кључне речи:
Ca2+ channels; K+ channels; MgSO4; Tocolytic; UterusИзвор:
Archives of Biological Sciences, 2019, 71, 1, 5-11Финансирање / пројекти:
- Молекуларни механизми редокс сигналинга у хомеостази, адаптацији и патологији (RS-MESTD-Basic Research (BR or ON)-173014)
URI
http://www.doiserbia.nb.rs/Article.aspx?ID=0354-46641800031Shttp://www.serbiosoc.org.rs/arch/index.php/abs/article/view/3064
https://radar.ibiss.bg.ac.rs/handle/123456789/3352