[Effect of AMG-1 on free intrasynaptosome calcium level and on the isolated artery contraction induced by norepinephrine].
Recently, the intracellular free calcium overload has been considered as an important factor in the development of ischemic brain damage. In this paper, the effect of AMG-1 on free calcium concentration ([Ca2+]i) in rat intrasynaptosome and on the isolated rat tail artery contraction induced by norepinephrine (NE) were studied by using Fura-2 fluorescence technique and contraction force measurement, respectively. The results show that: 1. AMG-1 10 mumol.L-1 and 100 mumol.L-1 reduced the KCl induced [Ca2+]i increase by 19 +/- 11% and 57 +/- 12%. 2. AMG-1 100 mumol.L-1 markedly decreased the NE-dependent intracellular calcium induced contraction force (43 +/- 11%). In our previous study, AMG-1 was shown to have improving effect on ischemic damage following middle cerebral artery occlusion in rats. On the basis of these results, we suggest that the mechanism of AMG-1 in improving cerebral ischemic damage may be due to the decrease of [Ca2+]i.
Li
W P
WP
Institute of Materia Medica, Chinese Academy of Medical Sciences, Beijing.
Feng
Y P
YP
Zhang
J T
JT
D000241:Adenosine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000818:Animals; D001158:Arteries / Q000187:drug effects; D002118:Calcium / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D009638:Norepinephrine / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013574:Synaptosomes / Q000378:metabolism*
C063248:6-(5-hydroxy-2-pyridylmethylamino)-9-beta-ribofuranosylpurine; D000241:Adenosine; D002118:Calcium; D009638:Norepinephrine