Abstract: The objective was to study the effects of cyclophosphamid on growth , peripheral blood biochemistry index and organ coefficient of SD rats. The rats were randomly divided into four groups, each was administered with corresponding concentration of cyclophosphamid by intraperitoneal injection for 7 days.The wet weights of heart ,liver,spleen ,lung ,kidney, thymus, testis, epididymis and brain of the rats were weighed after they were killed,and organ coefficients were calculated. Routine blood parameters, biochemical indices and electrolyte indicators of rat peripheral blood were measured. As a result,with the dose of cyclophosphamide increasing, body weight were significantly reduced; thymus and spleen index of cyclophosphamide treatment group was significantly lower than the control group with a dose-dependent manner; with the dose of cyclophosphamide increasing, the concentrations of PLT, RBC and Hb were significantly reduced. The results showed that with the increasing doses of cyclophosphamide, the immune function of animals showing gradual decline.

Key words: cyclophosphamide; SD rats; growth; blood biochemistry; organ coefficient