Ion channel mechanism and ingredient bases of Shenfu Decoction's cardiac electrophysiological effects.
OBJECTIVE
Ion channel mechanism of cardiac electrophysiological effects of Shenfu Decoction (SFD, Ginseng and Aconiti Praeparatae Decoction), a traditional Chinese medicine (TCM) prescription, and its ingredient bases were investigated in guinea pigs.


METHODS
After administration of an injection made from SFD (Shenfu Injection, SFI), the indexes of transmembrane action potential (TAP) in vivo and sodium channels in isolated ventricular myocyte were assayed by suspended microelectrodes and patch clamp techniques respectively, and ingredients of SFD were compared with.


RESULTS
After administration of SFI, the action potential amplitude (APA) and maximum velocity (V(max)) of TAP decreased. In the presence of either SFI or Fuzi active ingredient (FZAI)(5, 10, and 15%), not any other ingredient, the density of voltage-dependent sodium current (I(Na)) decreased significantly, while the inhibition ratio of SFI was larger. EC(50) of SFI was less than the one of FZAI, and SFI displayed effects on I(Na) in wider voltage scope than FZAI in current-voltage curve. Both SFI and FZAI shifted the steady-state inactivation curve of sodium channels to the left, and the recovery curve to the right.


CONCLUSIONS
The results indicated that the cardiac electrophysiological effects of SFI were exerted by blocking sodium channels, and FZAI contributed to such effects most but inferior to SFI, which justified its use in anti-arrhythmia, myocardial protection, etc.
Luo
Jie
J
Department of Anesthesiology, The First Affiliated Hospital, Chongqing Medical University, Chongqing 400016, China.
Min
Su
S
Wei
Ke
K
Cao
Jun
J
D031841:Aconitum / Q000737:chemistry; D000818:Animals; D002469:Cell Separation; D004305:Dose-Response Relationship, Drug; D004365:Drugs, Chinese Herbal / Q000737:chemistry* / Q000494:pharmacology*; D004594:Electrophysiology; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects*; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects*; D007700:Kinetics; D008564:Membrane Potentials / Q000187:drug effects; D032383:Myocytes, Cardiac / Q000187:drug effects*; D005894:Panax / Q000737:chemistry; D018408:Patch-Clamp Techniques; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D015222:Sodium Channels / Q000187:drug effects
D004365:Drugs, Chinese Herbal; D007473:Ion Channels; D010936:Plant Extracts; C492793:Shen-Fu; D015222:Sodium Channels