Abstract:
In order to assess the changes in adrenal gland in relation to blood glucose during trypanosomiasis, eleven sexually mature male white New Zealand rabbits were experimentally infected with Trypanosoma congolense (clone lL-3000) while 8 rabbits served as controls for 8 weeks. Parameters studied were body weights, body temperatures, packed cell volume (PCV), parasitaemia levels, liver weights and liver body weight ratio, adrenal gland weights and adrenal gland body weight ratio. Others were histological changes in the adrenal gland, plasma cortisol levels and plasma glucose levels. The cumulative mean weight gain (C.M.W.G) of the infected rabbits was significantly (P<0.05) lower compared to that of the control as from week three onwards.Infected rabbits had significantly (P<0.01) higher body temperatures compared to those of the control ones.The infected rabbits showed a significant (P<0.01) depression in PCV within two weeks of infection compared to the control ones. Values of 17-20% were obtained in most susceptible rabbits and the fall in PCV correlated closely with the intensity and duration of parasitaemia. Liver body weight ratio of the infected rabbits were significantly (P<0.0l) higher compared to those of the control ones. There was no significant (P>0.05) difference in adrenal gland weights and adrenal gland body weight ratio of the infected rabbits compared to those of the control ones. Histological changes in the adrenal gland showed that there was marked hypertrophy (measured as thickness of the cortices) in the infected rabbits. These changes were significantly (P<0.05) different in the infected rabbits compared to those in the control animals. The plasma cortisol levels were significantly (P<0.01) elevated in the infected rabbits compared to those of the control ones. However, there was no significant (R>0.05) difference in plasma glucose levels in the infected rabbits compared to those of the control ones. The evidence obtained in this study indicates that plasma glucose regulation is not affected in trypanosomiasis and the mechanism for gonadal hormones depression in trypanocidal infection may not apply in the case of glucocorticoids. Thus the steroids from different organs are probably affected differently in trypanosomiasis.
