|Budget Amount *help
¥3,300,000 (Direct Cost : ¥3,300,000)
Fiscal Year 1999 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1998 : ¥2,800,000 (Direct Cost : ¥2,800,000)
The effects of chronic administration of methamphetamine on brain tissues especially hyppocampus and mid brain were histopathologically studied in experimental models. Methamphetamine (1 ml/kg body weight/day) was subcutaneously injected into 14 five-week-old male Wistar Kyoto rats (WKY) for 12 weeks. Age and sex matched 5 WKY rats served as controls. With light microscopy, some scattered edematous lesions and moderate vacuolization were demonstrated in the brain of 8 of the methamphetamine treated rats. However, in 4 of the rats, severe regional hemorrhage, partial nerve cell necrosis, destruction of the nerve cells, glia cells infiltration, interstitial vessel dilatation, interstitial edema and fatty cell invasion were observed after the injections of methamphetamine. The small vessels had a slight degeneration of the endothelial cells. In the control animals, no lesions, except for some edematous lesions were found. In all cases, [CaィイD12+ィエD1]i responsibilities were studied using cholesistokinin-receptor B. However brain slices were not enough to get the distinct reactivity to cholesisitokinin, and only showed low reaction to the [CaィイD12+ィエD1]i stimulator drugs. In addition to the animal model, there were 4 autopsy cases of sudden death in chronic methamphetamine abusers. The autopsies demonstrated a severe acute necrotic hemorrhagic brain bleeding with only scattered slight glia cells in the brain. These findings indicate that chronic administration of methanphetamine to rats evoked significant changes in brain [CaィイD12+ィエD1]i responsibility, though tissues including some degeneration of the endothelial cells of the small vessels in this hypoxia-vulnerable organ.