Laminin Expression Pattern in the Histogenesis of the Dorsal Metencephalic Anlage

Although laminin is the first glycoprotein to be expressed during embryogenesis of the CNS and it is involved in the list of the fifty proteins responsible for recessive cognitive disorders in human. But its importance in the cerebellar development has not received much attention. This study is an attempt to shed light on the functional role of the laminin in the development of one of the key structures in the central nervous system. That is the cerebellum in order to clarify its therapeutic potential in the treatment of these disorders. The mammalian animal model of this study was the rat and the embryonic period covered in it, was from the embryonic day 15 till birth. E-designation system was used to determine the relevant developmental stages of (62) rat embryos. Embryonic samples were collected and processed for paraffin block then sectioned. Polyclonal anti laminin Ab was used to demonstrate laminin reactivity. Quantification of laminin Ab reactivity done using Aperio Alogrithm software. The results of the present study revealed that the laminin was present at the pial basement membrane delineating the dorsal surface of the developing cerebellum and concentrated at the fissures. It illustrated that the spatiotemporal variation of the laminin expression is correlated with the main cellular dynamic events occurring in the dorsal part of the metencephalon. This work concluded that laminin is a navigation cue for migration, proliferation, differentiation, neurite outgrowth and cell process dynamics in particular during complex embryonic development taking place in the dorsal metencephalic anlage