title: Crocin, a carotenoid component of Crocus cativus, exerts inhibitory effects on L-type Ca(2+) current, Ca(2+) transient, and contractility in rat ventricular myocytes.
abstract: Crocin, a carotenoid component of Crocus sativus L. belonging to the Iridaceae family, has demonstrated cardioprotective effects. To investigate the cellular mechanisms of these cardioprotective effects, here we studied the influence of crocin on L-type Ca(2+)current (I(Ca-L)), intracellular Ca(2+) ([Ca(2+)]i), and contraction of isolated rat cardiomyocytes by using the whole-cell patch-clamp technique and video-based edge detection and dual excitation fluorescence photomultiplier systems. Crocin inhibited I(Ca-L) in a concentration-dependent manner with the half-maximal inhibitory concentration (IC50) of 45 μmol/L and the maximal inhibitory effect of 72.195% ± 1.54%. Neither current-voltage relationship of I(Ca-L), reversal potential of I(Ca-L), nor the activation/inactivation of I(Ca-L) was significantly changed. Crocin at 1 μmol/L reduced cell shortening by 44.64% ± 2.12% and the peak value of the Ca(2+) transient by 23.66% ± 4.52%. Crocin significantly reduced amplitudes of myocyte shortening and [Ca(2+)]i with an increase in the time to reach 10% of the peak (Tp) and a decrease in the time to 10% of the baseline (Tr). Thus, the cardioprotective effects of crocin may be attributed to the attenuation of [Ca(2+)]i through the inhibition of I(Ca-L) in rat cardiomyocytes and negative inotropic effects on myocardial contractility.
authors.affiliation: a Hebei Medical University, No. 361, East Zhongshan Road, Shijiazhuang 050017, Hebei, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Liu
authors.affiliation: b The Fourth Hospital of Hebei Medical University, No. 12, Jiankang Road, Shijiazhuang 050011, Hebei, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Chu
authors.affiliation: a Hebei Medical University, No. 361, East Zhongshan Road, Shijiazhuang 050017, Hebei, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Wang
authors.affiliation: c Hebei University of Chinese Medicine, No. 3, Xingyuan Road, Shijiazhuang 050200, Hebei, China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: c Hebei University of Chinese Medicine, No. 3, Xingyuan Road, Shijiazhuang 050200, Hebei, China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: c Hebei University of Chinese Medicine, No. 3, Xingyuan Road, Shijiazhuang 050200, Hebei, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Guo
authors.affiliation: c Hebei University of Chinese Medicine, No. 3, Xingyuan Road, Shijiazhuang 050200, Hebei, China.
authors.forename: Zhenyi
authors.initials: Z
authors.lastname: Liu
authors.affiliation: d Intensive Care Unit, Air Force General Hospital, No. 30, Fucheng Road, Haidian 100142, Beijing, China.
authors.forename: Yongsheng
authors.initials: Y
authors.lastname: Dong
authors.affiliation: e Department of Infectious Diseases, Hebei General Hospital, Shijiazhuang, Hebei 050051, Shijiazhuang, China.
authors.forename: Hongying
authors.initials: H
authors.lastname: Liu
authors.affiliation: a Hebei Medical University, No. 361, East Zhongshan Road, Shijiazhuang 050017, Hebei, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: a Hebei Medical University, No. 361, East Zhongshan Road, Shijiazhuang 050017, Hebei, China.|c Hebei University of Chinese Medicine, No. 3, Xingyuan Road, Shijiazhuang 050200, Hebei, China.
authors.forename: Li
authors.initials: L
authors.lastname: Chu
authors.affiliation: a Hebei Medical University, No. 361, East Zhongshan Road, Shijiazhuang 050017, Hebei, China.|c Hebei University of Chinese Medicine, No. 3, Xingyuan Road, Shijiazhuang 050200, Hebei, China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D020746:Calcium Channels, L-Type / Q000378:metabolism*; D002338:Carotenoids / Q000494:pharmacology*; D027622:Crocus / Q000737:chemistry*; D006352:Heart Ventricles / Q000187:drug effects / Q000378:metabolism; D009200:Myocardial Contraction / Q000187:drug effects*; D009206:Myocardium / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000187:drug effects*; D018408:Patch-Clamp Techniques / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D020746:Calcium Channels, L-Type; D002338:Carotenoids; C029036:crocin; D002118:Calcium
keywords: Ca2+ transient; L-type Ca2+ current; courant Ca2+ de type L; courant Ca2+ transitoire; crocin; crocine; myocyte shortening; patch clamp; raccourcissement des myocytes; « patch clamp »