Effect of Alpha-Phenyl-N-Tert-Butyl Nitrone on Aging of the Cerebellum of Male Albino Rats (Histological and Immunohistochemical Study)

Introduction: Aging is an inevitable process that affects the cerebellum in addition to other body organs. Nitric oxide (NO) produced within the cerebellum mediates normal synaptic transmission. However, high amount of it has been hypothesized as a major contributor in disease pathway and aging. Aim of the Work: The present work was designed to assess the effects of aging on the cerebellum and the possible anti-aging effect of alpha-phenyl-N-tert-butyl-nitrone (PBN). Materials and Methods: Forty male albino rats were divided into 5 groups (N=8): Group 1 (Control Adult; 3 months old), Group 2 (Aged; 24 months old), Group 3 [PBN treated adult; received intraperitoneal (i.p) injection of 32 mg/kg B.W. of PBN twice daily for two weeks], Group 4 (PBN treated aged; received PBN in the same previous dose) Group 5 [DMSO treated aged; received i.p injection of DMSO; dimethyl sulfoxide (solvent) twice daily for two weeks]. Sections from the cerebellum were prepared and stained with H E, Cresyl fast violet stain, Hortega’s stain as well as immunohistochemical stain for inducible Nitric oxide synthase (iNOS) and neuronal NOS (nNOS). Results: In aged group, there was significant decrease in density of neurons in the cortical layers; however density of fibrous astrocytes increased significantly. Decreased Nissl granules in Purkinje cells, decreased nNOS immunostaining in cortical layers, increased number of immunopositive cells in deep nuclei and increased iNOS immunostaining in the cortex and deep nuclei were detected. In PBN treated aged group, there was slight improvement in the previous findings, compared to aged group. Conclusion: Two weeks of PBN treatment in aged rats produced slight improvement in the structure of the aged cerebellum, therefore it could be used in improving its function.