Chapter 20 Permissive and restrictive periods for brainstem-spinal regeneration in the chick

Publisher Summary This chapter focuses on the permissive and restrictive periods for brainstem-spinal regeneration in the chick. Studies of the development and organization of brainstem and spinal locomotor mechanisms indicate that birds are very similar to all other vertebrates. For example, the anatomical, physiological, and pharmacological organization of avian brainstem-spinal locomotor circuits is analogous to that of all other vertebrates, including mammal. Moreover, after a complete or incomplete spinal cord injury, adult birds suffer the same motor deficits as adult mammals. The chapter discusses an approach for the search of the cellular factors that underlie the transition between the permissive and restrictive periods for functional regeneration using a number of different techniques. It examines whether plasma membrane fractions, isolated from spinal cord tissue at different stages of development, were permissive or restrictive substrates for the in vitro differentiation and outgrowth of processes from membrane fractions, isolated from spinal cord immortalized neuronal-glial hybrid cell.