Morphological evaluation of rat cerebellum following administration of nitrogen monoxide precursor and inhibitor

Abstract

In this study, the quantitative and qualitative effects of nitrogen monoxide on cerebellar histopathology, by increasing or decreasing in vivo production of this substance, were investigated. In this study, forty Wistar female rats (RAT) with a weight of about 200 to 250 grams and an average age of eight weeks were used. Rats were divided into five groups of eight, including control groups, normal saline, L-NAME, L-Arginine, L-NAME + L-Arginine. On the third, fourth and fifth days, the injection was performed intraperitoneally and on the eighteenth day, after anesthesia with ether and then craniotomy, the brain and cerebellum of the animals were removed and After quantitative measurements including weight and volume, organs were fixed in 10% formalin and after tissue preparation steps, to prepare the slide, sections with a thickness of 5 to 6 microns were prepared from the samples and by general method such as Hematoxylin-eosin and special techniques like Mason trichrome and toluidine blue were stained and evaluated. The results of this study show that in the case of cerebellum, there is no significant difference in the quantitative weight parameter between the control groups, normal saline, L-Arg, L-NAME and L-NAME + L-Arg groups. Regarding the volume parameter, a significant increase (P <0.01) was observed in L-Arg group compared to L-NAME, L-Arg + L-NAME and normal saline groups. In microscopic qualitative parameters, the most changes in the L-Arg group were seen as follows: The granular and molecular layers of the cerebellum became slightly thickened, some of the nuclei in the granular and molecular layers became severely hyperchromatized, and Purkinje cell accumulation was seen with lymphocytic invasion. In the other groups, there were no significant changes. It is inferred from this study that L-Arginine can cause histopathological changes in cerebellar tissue by increasing NO levels in cerebellum. However, in this study, unlike other similar studies, L-NAME injection did not cause significant histopathological change.