[Effects of hydrocortisone sodium succinate on sodium current in human and guinea pig cardiac myocytes].
OBJECTIVE
To study the effects of hydrocortisone sodium succinate on sodium current in human atrial myocytes and in guinea pig ventricular myocytes.


METHODS
Single cardiac myocytes were isolated by enzyme. The effects of hydrocortisone sodium succinate on sodium current (INa) were assessed by applying whole-cell patch clamp techniques.


RESULTS
Hydrocortisone sodium succinate (1, 3, 10 micromol x L(-1)) was shown to inhibit INa of both human atrial myocytes and guinea pig ventricular myocytes in concentration dependent manner and the IC50 were 6.97 and 8.74 micromol x L(-1), respectively. The inhibition effects acted quickly (1-3 min) and the maximal activating voltage of INa was not changed in both human and guinea pig cardiac myocytes.


CONCLUSIONS
Hydrocortisone sodium succinate can exhibit inhibitory effects on INa in both human and guinea pig cardiac myocytes, and its inhibitory effects act rapidly, which are not consistent with genomic effects, so there may be nongenomic effects.
Hu
Zhuang-li
ZL
Department of Pharmacology, Tongji Medical College of Huazhong University of Science and Technology, Wuhan 430030, China.
Liu
Hui
H
Hu
Yan
Y
Zhang
De-yong
DY
Sun
Zong-quan
ZQ
Jin
Man-wen
MW
D000293:Adolescent; D000328:Adult; D000818:Animals; D002469:Cell Separation; D002648:Child; D002675:Child, Preschool; D006168:Guinea Pigs; D006325:Heart Atria / Q000473:pathology; D006330:Heart Defects, Congenital / Q000473:pathology; D006352:Heart Ventricles / Q000166:cytology; D006801:Humans; D006854:Hydrocortisone / Q000031:analogs & derivatives* / Q000494:pharmacology*; D032383:Myocytes, Cardiac / Q000187:drug effects / Q000502:physiology*; D018408:Patch-Clamp Techniques; D015222:Sodium Channels / Q000187:drug effects*
D015222:Sodium Channels; C007133:hydrocortisone hemisuccinate; D006854:Hydrocortisone