title: New Findings on the Effects of Tannic Acid: Inhibition of L-Type Calcium Channels, Calcium Transient and Contractility in Rat Ventricular Myocytes.
abstract: Tannic acid (TA) is a group of water-soluble polyphenolic compounds that occur mainly in plant-derived feeds, food grains and fruits. Many studies have explored its biomedical properties, such as anticancer, antibacterial, antimutagenic, antioxidant, antidiabetic, antiinflammatory and antihypertensive activities. However, the effects of TA on the L-type Ca(2+) current (ICa-L) of cardiomyocytes remain undefined. The present study examined the effects of TA on ICa-L using the whole-cell patch-clamp technique and on intracellular Ca(2+) handling and cell contractility in rat ventricular myocytes with the aid of a video-based edge detection system. Exposure to TA resulted in a concentration- and voltage-dependent blockade of ICa-L, with the half maximal inhibitory concentration of 1.69 μM and the maximal inhibitory effect of 46.15%. Moreover, TA significantly inhibited the amplitude of myocyte shortening and peak value of Ca(2+) transient and increased the time to 10% of the peak. These findings provide new experimental evidence for the cellular mechanism of action of TA and may help to expand clinical treatments for cardiovascular disease.
authors.affiliation: Hebei Medical University, 361 East Zhongshan Road, Shijiazhuang, 050017, Hebei, China.
authors.forename: Fengli
authors.initials: F
authors.lastname: Zhu
authors.affiliation: The Fourth Hospital of Hebei Medical University, Shijiazhuang, 050011, Hebei, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Chu
authors.affiliation: Hebei Medical University, 361 East Zhongshan Road, Shijiazhuang, 050017, Hebei, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Pharmacology, Hebei University of Chinese Medicine, Shijiazhuang, 050200, Hebei, China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Medicinal Chemistry, Hebei University of Chinese Medicine, Shijiazhuang, 050200, Hebei, China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Medicinal Chemistry, Hebei University of Chinese Medicine, Shijiazhuang, 050200, Hebei, China.
authors.forename: Zhenyi
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Medicinal Chemistry, Hebei University of Chinese Medicine, Shijiazhuang, 050200, Hebei, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Guo
authors.affiliation: Department of Infectious Diseases, Hebei General Hospital, No. 348, Heping West Road, Shijiazhuang, Hebei, 050051, China.
authors.forename: Hongying
authors.initials: H
authors.lastname: Liu
authors.affiliation: Hebei Medical University, 361 East Zhongshan Road, Shijiazhuang, 050017, Hebei, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Hebei Medical University, 361 East Zhongshan Road, Shijiazhuang, 050017, Hebei, China.|Department of Pharmacology, Hebei University of Chinese Medicine, Shijiazhuang, 050200, Hebei, China.
authors.forename: Li
authors.initials: L
authors.lastname: Chu
authors.affiliation: Hebei Medical University, 361 East Zhongshan Road, Shijiazhuang, 050017, Hebei, China.|Department of Pharmacology, Hebei University of Chinese Medicine, Shijiazhuang, 050200, Hebei, China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D020746:Calcium Channels, L-Type / Q000187:drug effects* / Q000378:metabolism; D006352:Heart Ventricles / Q000166:cytology / Q000187:drug effects*; D009119:Muscle Contraction / Q000187:drug effects*; D032383:Myocytes, Cardiac / Q000187:drug effects*; D018408:Patch-Clamp Techniques; D010936:Plant Extracts / Q000494:pharmacology; D051381:Rats; D013634:Tannins / Q000494:pharmacology*
chemical_list: D002121:Calcium Channel Blockers; D020746:Calcium Channels, L-Type; D010936:Plant Extracts; D013634:Tannins; D002118:Calcium
keywords: Ca2+ channel; Ca2+ transient; Tannic acid; cardiomyocyte; myocyte shortening