Abstract: ObjectiveTo explore the noxious effect and the extent of damage in nigra-striatum neuron of bilirubin.Methods30 newborn rabbits were divided into 3 groups randomly:control group(group C,12 rabbits) which were injected normal salt intraperitoneally,model group 1(group N₁,12 rabbits) which were injected bilirubin 100mg/kg intraperitoneally, model group 2(group N₂,12 rabbits) which were injected bilirubin 200mg/kg intraperitoneally. All the rabbits in group C and 6 rabbits in group N1(group N_1a) and group 2(group N_2a) were killed 6 hours after injection.Other 6 rabbits in group N1(group N_1b) and group 2(group N_2b) were killed 16 hours after injection. The quantity of neuron in nigra-striatum were determined,and the changes of ultrastructure were observed by electron microscope.ResultsThe neuron in nigra-striatum in group N_2b were decreased compared with group C and group N_1a(P<0.05),as well as with group N_1b and N_2a. The ultrastructure of the neuron was changed.ConclusionsThe changes in utrastructure and the quantity of nigra-striatum neuron were associated with the concentration and time of exposure under bilirubin. It is consisted with the changes of ultrastructrue and quantity in nigra-striatum.

Key words: bilirubin encephalopathy, nigra-striatum, rabbit