BACKGROUND Huangjiao granule is pure Chinese drugs pharmaceutics which can eliminate heat by purgating fu-organs clear unconsciousness and stop endogenous wind as well as promote blood flow and remove blood stasis etc. OBJECTIVE To observe the effect of huangjiao granule on apoptosis of neurocytes in rat models with middle cerebral arterial occlusion and probe into the possible mechanism of huangjiao granule in the treatment of acute cerebral infarction. DESIGN Complete randomized grouping design control animal experiment. SETTING Department of Neurology Affiliated Hospital of Traditional Chinese Medicine Combined with Western Medicine Tongji Medical College of Huazhong University of Science and Technology. MATERIALS The experiment was conducted in the Central Laboratory Hubei College of Traditional Chinese Medicine. Sixty old Wistar rats aged 22 months were selected. After 3-day-feeding for adaptability rats were randomized into 6 groups according to body mass Normal control group model group nimodipine gorup 10 g/kg huangjiao granule group and 5 g/kg huangjiao granule group with 10 rats in each group. METHODS ①Rats were made into cerebral ischemic models with middle cerebral arterial occlusion method. Thirty minutes before modeling rats in the 10 5 2.5 g/kg huangjiao granule main gredients were radix et rhizoma rhei cornu bubali etc. provided by Manufacturing Laboratory of Wuhan First Hospital with the batch number of 021120 groups respectively received gastric perfusion of 1 0.5 0.25 g/mL huangjiao water solution containing crude drug at the dose of 10 5 2.5 g/kg with each rats perfused once Rats in the nimodipine group received gastric perfusion of 1 mg/mL nimodipine water solution containing crude drug at the dose of 10 mg/kg with each rats perfused once Rats in the model group and normal control group received gastric perfusion of normal saline at the dose of 10 mL/kg with each rats perfused once. ② Apoptotic stainning sections in situ were observed under light microscope 5 fields were observed under high power 20×10. Observed the number of mean positive cells of each highpower field and then caculated the percentage of apoptosis.
Histologic changes of local and peripheral ischemic cortexes were observed under light microscope. Changes of ultramicrostructure of cells in cerebral cortexes of rats were observed under electron microscope.③Differences of measurement data were compared with F test and Q test. MAIN OUTCOME MEASURES Morphologic effects of huangjiao granule on apoptotic rate of neurocytes in brain tissues of old rats with middle cerebral arterial occlusion MACO and cells in cerebral cortexes. RESULTS A total of 60 Wistar rats were involved in the analysis of results. ①Number of apoptotic positive cells in brain tissues and apoptotic rate in rats of model group were significantly higher than those in the normal control group P < 0.01 Those in each huangjiao granule groups and nimodipine group were obviously lower than those in the model group P < 0.01 Differences in numbers of apoptotic positive cells in brain tissues and apoptotic rates in rats of 10 g/kg huangjiao group and nimodipine group were not obvious P < 0.05. Number of apoptotic positive cells in brain tissues and apoptotic rate in rats of 10 g/kg huangjiao granule group were markedly lower than those in the 5 2.5 g/kg huangjiao granule groups P < 0.05 0.01.②Observation with light microscope and electron microscope showed that there were obvious apoptosis in local cells of brain tissues in rats of model group which can significantly ameliorate by haungjiao granule. CONCLUSION Huangjiao granule has some antagonistic effects on acute ischemic apoptosis of neurocytes which may be one of the possible mechanisms of huangjiao granule in the treatment of acute cerebral infarction.