Electron microscopic observation of normal and 2,4,5-trihydroxyl phenylethylamine (6-hydroxydopamine) lesioned corpus striatum in Wistar Albino rats

Background: The prevalence and incidence of Parkinson's disease (PD) is increasing due to a prolonged life expectancy. The cardinal features of PD include resting tremor, rigidity, bradykinesia, and postural instability. In rodents the 2,4,5-trihydroxyphenylethylamine [6-hydroxydopamine (6-OHDA)] induced lesion of the nigrostriatal system showed retrograde degeneration and structural changes in the corpus striatum under transmission the electron microscope (TEM). Aim and Objectives: To study the ultra-structure of normal and 6-OHDA lesioned corpus striatum in Wistar albino rats under the transmission electron microscope. Material and Methods: Wistar albino male adult rats received unilateral stereotaxical injection of 6-OHDA on the right side of striatum and were sacrificed after 120 days. The following stereotaxic co-ordinates were used to target the dorsolateral part of the striatum: AP = 0.2 mm, ML = 3.2 mm, DV = 4.5 mm from the bregma. Another target was the dorsomedial part of striatum: AP = 1.1 mm, ML = 2.4 mm and DV = 3.5 mm.The motor behavior was monitored in cylinder which was counted for a period of 60 min. Results and Conclusion: Our TEM finding in the control rats demonstrated that nucleus was round and comparatively large in proportion to the cell body and lies in the centre of the nerve cell in the striatum. Occasionally one or two dense nucleoli were located eccentrically in the nucleoplasm. Additionally, in the cytoplasm around the nucleus, the conspicuous organelles along with the numerous ribosomes which were mostly free and appear as rosettes or clusters, some of which were attached to the endoplasmic reticulum. Furthermore, few short of granular endoplasmic reticula were seen. Interestingly, the lesioned rats showed neuronal and glial cells damage at the ultra-structural level in striatum under TEM observation.