title: Effects of the venom of the spider Ornithoctonus hainana on neonatal rat ventricular myocytes cellular and ionic electrophysiology.
abstract: Cardiac ion channels are membrane-spanning proteins that allow the passive movement of ions across the cell membrane along its electrochemical gradient, which regulates the resting membrane potential as well as the shape and duration of the cardiac action potential. Additionally, they have been recognized as potential targets for the actions of neurotransmitters, hormones and drugs of cardiac diseases. Spider venoms contain high abundant of toxins that target diverse ion channels and have been considered as a potential resource of new constituents with speciﬁc pharmacological properties. However, few peptides from spider venoms were detected as cardiac channel antagonists. In order to explore the effects of the venom of Ornithoctonus hainana on the action potential and ionic currents of neonatal rat ventricular myocytes (NRVMs), whole cell patch clamp technique was used to record action potential duration (APD), sodium current (INa), L calcium current (ICaL), rapidly activating and inactivating transient outward currents (Ito1), rapid (IKr) and slow (IKs) components of the delayed rectifier currents and the inward rectifier currents (IK1). Our results showed that 100 μg/mL venom obviously prolonged APDs. Signiﬁcantly, the venom could inhibit INa and ICaL effectively, while no evident inhibitory effects on cardiac K(+) channels (Ito1, Iks, Ikr and Ik1) were observed, suggesting that the venom represented a multifaceted pharmacological profile. The effect of venom on Na(+) and Ca(2+) currents of ventricular myocytes revealed that the hainan venom as a rich resource of cardiac channel antagonists might be valuable tools for the investigation of both channels and drug development.
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Yiya
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Jinyan
authors.initials: J
authors.lastname: Liu
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Zhonghua
authors.initials: Z
authors.lastname: Liu
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Meichi
authors.initials: M
authors.lastname: Wang
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Lu
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhu
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China. Electronic address: xiongzhizeng@gmail.com.
authors.forename: Xiongzhi
authors.initials: X
authors.lastname: Zeng
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China. Electronic address: liangsp@hunnu.edu.cn.
authors.forename: Songping
authors.initials: S
authors.lastname: Liang
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D000831:Animals, Newborn; D020746:Calcium Channels, L-Type / Q000187:drug effects / Q000378:metabolism; D055724:Electrophysiological Phenomena / Q000187:drug effects*; D005260:Female; D007473:Ion Channels / Q000187:drug effects* / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000187:drug effects*; D018408:Patch-Clamp Techniques; D051381:Rats; D015222:Sodium Channels / Q000187:drug effects / Q000378:metabolism; D013111:Spider Venoms / Q000633:toxicity*
chemical_list: D020746:Calcium Channels, L-Type; D007473:Ion Channels; D015222:Sodium Channels; D013111:Spider Venoms
keywords: Action potential duration; Ion channels; Ornithoctonus hainana; Spider venom; Ventricular myocytes