NS-7 is a novel, voltage-dependent Na(+) and Ca(2+) channel blocker. This study evaluated the in vivo
neuroprotective effect of
NS-7 in a rat transient focal ischemic model when administered during occlusion. Left
middle cerebral artery occlusion was induced in adult male Sprague-Dawley rats for 120 min using an intraluminal thread method. The rats received a single
intravenous injection of
NS-7 or saline (control group) just after the onset of
ischemia, and at 30, 60 and 120 min after
ischemia. Their brains were removed after 48 h reperfusion, sectioned, and stained with
hematoxylin and
eosin. Animals were evaluated by neurological examination at 120 min
ischemia and 48 h reperfusion. Infarcted cortex and striatum were measured quantitatively and
infarction volumes were calculated. Cortical
infarction volumes were 128+/-74 (NS-7) and 214+/-64 mm(3) (control) immediately after the
ischemia group, 155+/-48 (NS-7) and 225+/-12 mm(3) (control) after the 30 min group, 160+/-54 (NS-7) and 225+/-48 mm(3) (control) after the 60 min group, and 176+/-43 (NS-7) and 223+/-38 mm(3) (control) after the 120 min group. Cortices in NS-7-treated groups were significantly less infarcted than in control groups at all treatment times. There was no significant difference in the striatal
infarction volume between the treatment and control groups. Neurological examination showed that
hemiparesis and abnormal posture of the
NS-7 groups were significantly more improved at 48 h reperfusion than those of the control groups without posture examination in the 120 min group. These observations suggest that
NS-7 may be a new potential therapeutic agent for the acute phase of
cerebral infarction.