Microstructural Observations on Nissl Substances in the Cerebellar Cortex of Adult Wistar Rats following Quinine Administration

Purpose: This study assessed some microstructural effects of quinine, commonly used in malaria chemotherapy, especially in chloroquine-resistant and cerebral malaria, on the Nissl substance in the cerebellar cortex of adult Wistar rats using microanatomical studies. Methods: Twenty seven adult male Wistar rats, weighing between 150g and 190g, were randomly separated into groups A, B and C (n=9). The rats in group A served as the control and received intramuscular injection of physiological saline. Group B rats were injected intramuscularly with liquid quinine, 16mg/kg body weight as a start dose, followed by 8mg/kg body weight 8 hourly for seven days. Group C rats received the same treatment as group B but were subjected to a withdrawal period of one week. Groups A and B rats were sacrificed at the end of the treatment while group C rats were sacrificed at the end of one week. The cerebellum of each rat was removed and fixed in 10% formol saline for histological analysis. Results: The findings showed that the Nissl substances in the cerebellar cortex in control rats stained more intensely and distinctly compared with the less intense stain and degenerated Nissl substances in the treated rats. Conclusion: The observed degenerative changes in the Nissl substances in the cerebellar cortex of the treated rats may affect the synthesis of proteins in correlation with neuronal functions.