The use of neuroprotective drugs is one of the numerous methods for
the treatment of patients with acute ischemir stroke.The aim of this study
is the detection of the effect of vinpocetine (VP) and adenosine each alone
and in combination on size of cerebral infarction induced in rats by ligation
of common carotid artery (CCA). Also, the effect of both drugS on cerebral
blood flow and on pentylene-tetrazole(PTZ) induced convulsions in
rats was studied.
Regarding the effect of VP and adenosine on cerebral infarction in rats,
this study showed that administration of VP in a dose of 0.1 mg/ kg infraperitonealaP)
to the rats before ligation of CCA caused a significant reduction
in infarction size to 25.85 + 2.06% compared to 46.67 + 4.21% in infarcted
non-treated group of rats and in serum CPK level to 768 + 32.12
1U/ L compared to 1988 + 154.66 IU/L in infarcted non-treated group.
When adenosine injected II' in a dose of 1 mg/ kg to rats before Ligation
of CCA, it caused also a significant reduction in infarction size to
32.16 ±3.12% and in CPK level to 823 + 37.12 1U/ L compared to infarcted
non-treated group. Co-administration of VP & adenosine in same doses
mentioned above resulted in a significant reduction in infarction size to
15.12 +1.38% and in CPK level to 499.72 + 57.13 1U/ L when compared to
corresponding values in groups given each drug alone.
Concerning the effect of VP and adenosine on CCA blood flow, it was
found that VP in a dose of 0.1 mg /kg III' caused a significant increase in
CCA blood flow reaching its maximum effect after 30 minutes(min) to
about 56% of its basal value,then decreasing gradually to its basal value after 2 hours(h).Also,adenosine in a dose of I mg/ kg IP increased CCA
blood flow to a maximum effect 43.5% of its basal value after 30 mirt,then
decreasing to its basal value after 2 h. When both drugs given together in
same doses as before, they caused a marked increase in CCA blood flow
reaching its maximum effect to 72.7% of its basal vat, se after 30 min_
This study also showed that each of VP in a dose of 0.1 mg/ kg IP and
adenosine in a dose of 1 mg/kg IP caused a significant reduction in duration
of colonic seizures induced in rats by PIZ When both drugs given together,
they caused a more significant reduction in duration of P72-
induced convulsions than each drug alone. When theophylline (nonspecific
antagonist of adenosine) given in a dose of 5 mg/kg IP with VP ,it
caused a significant increase in duration of P72-induced convulsions in
rats compared to group given VP alone.
In conclusion, adenosine increased the effect of VP in protection against
cerebral infarction induced in rats by ligation of CCA and in protection
against P72-induced convulsions in rats. |