Neuroprotective effects and mechanisms of Cerebroprotein Hydrolysate for Injection (Ⅰ) on vascular dementia in rats / 药物评价研究

ABSTRACT

Objective To investigate the neuroprotective mechanisms of Cerebroprotein Hydrolysate for Injection (Ⅰ) on vascular dementia in rats.Method The rat vascular dementia model was prepared using an improved two-vessel occlusion method,and the common carotid artery was only isolated but not blocked in sham group.Rats were randomly divided into sham group,model group,Cerebroprotein Hydrolysate for Injection (Ⅰ) groups with low,medium and high dose (5,10,20 mg/kg) and Cerebroprotein Hydrolysate Injection group (Cerebrolysin,Positive drug,10 mg/kg).The drug was administered by iv injection of rat tail vein once a day for two weeks,while the same volume of saline was administered in sham and model group.At the end of administration,the plasma was collected through abdominal aorta to separate serum,and rat cortex was isolated to prepare homogenate.The levels of nerve growth factor (NGF) and insulin-like growth factor 2 (IGF-2) in serum and level of gamma-aminobutyric acid (GABA) in cortex were detected by ELISA.Level of glutamate (Glu) in cortex of VaD rats was detected by colorimetry.Results Compared with model group,levels of NGF and IGF-2 in the serum of VaD rats and level of GABA in cortex were significantly increased,while level of Glu in cortex was significantly decreased after administration of Cerebroprotein Hydrolysate for Injection (Ⅰ).The increased IGF-2 and GABA levels by Cerebroprotein Hydrolysate for Injection (Ⅰ) were significantly higher than that of Cerebrolysin at same dose.Conclusion The mechanisms underlying the increased leaming and memory ability of VaD rats by Cerebroprotein Hydrolysate for Injection (Ⅰ),are possibly related to the increased levels of NGF and IGF-2 in body and a regulation of the balance between excitatory and inhibitory amino acid neurotransmitters.