title: Influence of cyclovirobuxine D on intracellular [Ca(2+)] regulation and the expression of the calcium cycling proteins in rat myocytes.
abstract: Our previous studies have shown that cyclovirobuxine D (CVB-D) ameliorated the cardiac function in heart failure rats. Considering the relationship between cardiac function and [Ca(2+)]i, and the role of calcium cycling on regulating [Ca(2+)]i, the present study was designed to evaluate the influence of CVB-D on the calcium transient of myocytes from neonatal rats and adult heart failure (HF) rats. The expression of calcium cycling proteins, including L-type calcium channel (LTCC), ryanodine receptor 2 (RYR2), sarcoplasmic reticulum calcium ATPase 2a (SERCA2a) and sodium-calcium exchanger (NCX), were investigated to explore the underlying mechanism. CVB-D increased the intensity of calcium transient, accelerated the process of calcium transient and attenuation in the neonatal and adult myocytes. Furthermore, CVB-D shortened T(peak) and T(attenuation) in the adult myocytes and slowed down the heart rate of neonatal myocytes. Besides, CVB-D increased the expression of RYR2 and SERCA2a, decreased the expression of NCX, but showed no significant effect on LTCC. Thus, it was concluded that CVB-D increased the release and uptake of Ca(2+) in systolic and diastolic period, respectively. CVB-D might not only facilitate the utilization of intracellular Ca(2+), but also prevent the loss of Ca(2+).
authors.affiliation: Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Traditional Chinese Medicine, Nanjing, Jiangsu, PR China. nzyyubin@163.com
authors.forename: Bin
authors.initials: B
authors.lastname: Yu
authors.forename: Ming
authors.initials: M
authors.lastname: Ruan
authors.forename: Lingling
authors.initials: L
authors.lastname: Zhou
authors.forename: Li
authors.initials: L
authors.lastname: Xu
authors.forename: Taihui
authors.initials: T
authors.lastname: Fang
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects*; D008297:Male; D015394:Molecular Structure; D032383:Myocytes, Cardiac / Q000187:drug effects* / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D004365:Drugs, Chinese Herbal; C032939:cyclovirobuxine D; D002118:Calcium