ABSTRACT
Trypanosomosis is a major public health problem to man, which has a higher incident in tropical Africa. Protozoan parasite of the genus Trypanosoma causes the disease and it has been shown to have a fatal neurological effect if left untreated. The aim of the study is to compare the effect of Trypanosoma brucie brucie (T. brucei) and Trypanonsoma congolense (T. congolense) infection on the hematological indices, histology of the frontal lobe of the cerebrum, pineal gland and glia cell (astrocytes) GFAP immunoreactivity in the dentate gyrus of adult Wistar rats. Infected blood of about 0.5ml containing an inoculum dose of approximately 2.0 x 106 live T. b brucie (Fadare Strain) and T. congolense (Sahara strain) parasites for group two and three respectively was used to infect apparently healthy twenty Wistar rats (ten animals for each group) intraperitoneally. Eight other rats served as uninfected controls. Trypanosomes were detected in the blood of T. b brucie infected rats 2-3 days post-infection (PI) due to its virulent nature and in the blood of T. congolense infected rats 14 days PI. Parasitemia was estimated using blood smear from tail vein 24hours post infection to monitor disease progression, 7 days PI T. b brucie infected groups was humanely sacrificed while T. congolense infected group was sacrificed on day 21 PI. Brain tissue of the Wistar rats was processed histologically and stained with H and E and GFAP anti body, after which astrocyte cell count was done. Blood of the wistar rats was also taken and their haematological parameters analyzed. Hematological parameters such as hemoglobin, pack cell volume, white blood cell, white blood cells, platelet count etc were observed to decreased in the infected groups as compared to the control, Histological changes such as pyknotic pyramidal cells (indicative of dead cell) was observed in the infected groups when compared with the control; more also this study shown that T.congolense caused more neaurodegeneration compared to T. Brucie brucie: by significant (p<0.05) increase in the number of mean astrocyte cells in the dentate gyrus of the hippocampus (control: 80.60 � 10.08, T.b brucie 169.80 � 20.96, T. congolense 225.80 � 18.16)Trypanosoma brucie brucie is more virulent than T. congolense and causes more negative changes in the blood parameters; however, T. congolense infection caused severe histological changes in the cytoarchitexture of the frontal lobe of the cerebrum and pineal gland with subsequent hyper activation of the astrocyte in the dentate gyrus of the hippocampus compared to T.b brucie. Key words: Trypanosome brucie brucie, Trypanasome congolense, brain tissue, dentate gyrus of the hippocampus, Glial fibrillary acidic protein (GFAP).