Intranasal Delivery Of Insulin-like Growth Factor-1 And Its Resulting In Protection Against Hypoxic-ischemic Brain Damage In Neonatal Rats

Objective: (1)To research the protective pherapeutical effect of insulin-like growth factor -1 from hypoxic-ischemic brain damage.(2)To search a simple ,cost-effective and noninvasive medication to central nervous system,establish the feasibility and reliability of intranasal delivery of insulin-like growth factor-1 to central nervous system via olfactory. To search for the valid administration route and utility action time of nerve-protecrive treatment for hypoxic-ischemic brain damage and other central nervous systemic disease.Methods: eighty and four 7-day-old Wistar rats were randomly divided into four groups:sham control group(with 20 rats),drug-treated group(with 20 rats), IGF-1-treated group(with 24 rats),and model saline control group(with 20 rats). Drug-treated group and IGF-1-treated group was respectively delivered by intranasal with C.D.P.C 12.5ug(dissolved with 0.1ml saline)and IGF-12.5ug (dissolved with 0.1ml saline)after HIBD 1 hour, and model saline control group was delivered by intranasal with 0.1ml saline.Meanwhile sham control group only split common carotid artery without deligation and hypoxia.All animals were killed respectively at 24hours,72 hours,120 hours,and 168 hours after hypoxia.The pathology image analysis sofeware was used to measure the cortex infact square ratio and hippocampus necrosis neurons ratio.Terminal transferase-mediated dUTP nick end labeling(TUNEL)were used to measure the hippocampus apoptosis neurons number,and HE staining were used to observe the pathomorphologic changes.Meanwhile the behaval capability changes was observed. Results:1.The whole brain specimens were finded that:obvious cerebral edema and infarct focus were not finded on model saline control group,and light midrange cerebral edema were finded at deligated side of brain on other three groups,and cerebral cortex infarct focus were finded at part of specimen of other three groups .The number and volume of cerebral cortex infrct focus on IGF-1-treated group were all smaller than it of drug-treated group and model saline control group.The degree of injury on IGF-1-treated group were lower than it of drug-treated group,and it on drug-treated group were lower than it of model saline control group.2. The pathological changes were observed by light microscope on HIBD group.The brain tissue slices show that neuron cell degeneration and necrosis,the neurondondrite decrease or...