[Calcium channel blockade and anti-free-radical actions of panaxadiol saponins Rb1, Rb2, Rb3, Rc, and Rd].
OBJECTIVE
To identify the calcium channel blockade and anti-free-radical actions of panaxadiol saponins Rb1, Rb2, Rb3, Rc, and Rd.


METHODS
On ventricular myocardiocytes of Wistar rats, single channel activities of L, T, and B type Ca2+ channels were recorded with the cell-attached configuration of patch-clamp technic, and free radical contents were measured with electron spin resenance method.


RESULTS
Rb1, Rb2, Rb3, and Rc 200 mumol.L-1 shortened the open times, prolonged the close times, and reduced the openstate probabilities of calcium channels and 30 mumol.L-1 antagonized the increase of free radical content induced by xanthine 0.42 mmol.L-1-xanthine oxidase 5.3 nmol.L-1, but Rd in the same dose behaved none of the effects.


CONCLUSIONS
Rb1, Rb2, Rb3, and Rc had both the calcium channel blockade and anti-free-radical actions.
Zhong
G G
GG
Department of Physiology, Norman Bethune Medical University, Changchun, China.
Sun
C W
CW
Li
Y Y
YY
Qi
H
H
Zhao
C Y
CY
Jiang
Y
Y
Wang
X M
XM
Yang
S J
SJ
Li
H
H
D000818:Animals; D000831:Animals, Newborn; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D015220:Calcium Channels / Q000187:drug effects; D002478:Cells, Cultured; D016166:Free Radical Scavengers / Q000494:pharmacology*; D036145:Ginsenosides; D009206:Myocardium / Q000166:cytology*; D005894:Panax / Q000737:chemistry; D010946:Plants, Medicinal; D051381:Rats; D017208:Rats, Wistar; D012503:Saponins / Q000494:pharmacology*; D014315:Triterpenes / Q000494:pharmacology*
D002121:Calcium Channel Blockers; D015220:Calcium Channels; D016166:Free Radical Scavengers; D036145:Ginsenosides; D012503:Saponins; D014315:Triterpenes; C004564:panaxadiol