Gene profiling of intermediolateral column, medial, and lateral motoneuron after spinal cord transection

To determine spinal cord injury (SCI) induced changes in gene expression, laser capture microscopy (LCM) and Affymetrix microarrays were used to profiles three distinct populations of motor neurons (MNs) in five sets of littermates. In each set, one littermate received a lamenectomy (sham operated), and the other received a complete spinal cord transection. Each MN population was caudal to the transection and not axotomized. Thus, MNs in transected animals were responding to two major insults: deafferentation and changing microenvironments due to spreading immune and inflammatory responses. A total of 30 expression profiles from sham operated control animals have been uploaded to GEO database with accession number GSE2595. The current series contains 32 motoneuron expression profiles from spinalized mice. All chips (30 sham + 32 transection) were generated together using RMA in 2004. In this study we determine SCI induced changes in gene expression in lateral motoneurons (LMN), medial motoneurons (MMN) and intermediolateral column motoneurons (IML). Five sets of male littermates were used in these experiments (sets a-e). In each set, one littermate received a lamenectomy (sham operated), and the other received a complete spinal cord transection. Four of the sets (a-d) consisted of one transect and one littermate sham operated control. The fifth set (e) had an additional transect. All surgeries were performed on postnatal day (P) 24. Three weeks later (P45), the animals were sacrificed and their spinal cords were removed and sectioned for LCM. Each of the three cell types was captured from every animal. The expression profiles of the three classes of MNs were obtained using Affymetrix microarrays.