title: Expression of Semaphorins, Neuropilins, VEGF, and Tenascins in Rat and Human Primary Sensory Neurons after a Dorsal Root Injury.
abstract: Dorsal root injury is a situation not expected to be followed by a strong regenerative growth, or growth of the injured axon into the central nervous system of the spinal cord, if the central axon of the dorsal root is injured but of strong regeneration if subjected to injury to the peripherally projecting axons. The clinical consequence of axonal injury is loss of sensation and may also lead to neuropathic pain. In this study, we have usedin situhybridization to examine the distribution of mRNAs for the neural guidance molecules semaphorin 3A (SEMA3A), semaphorin 3F (SEMA3F), and semaphorin 4F (SEMA4F), their receptors neuropilin 1 (NP1) and neuropilin 2 (NP2) but also for the neuropilin ligand vascular endothelial growth factor (VEGF) and Tenascin J1, an extracellular matrix molecule involved in axonal guidance, in rat dorsal root ganglia (DRG) after a unilateral dorsal rhizotomy (DRT) or sciatic nerve transcetion (SNT). The studied survival times were 1-365 days. The different forms of mRNAs were unevenly distributed between the different size classes of sensory nerve cells. The results show that mRNA for SEMA3A was diminished after trauma to the sensory nerve roots in rats. The SEMA3A receptor NP1, and SEMA3F receptor NP2, was significantly upregulated in the DRG neurons after DRT and SNT. SEMA4F was upregulated after a SNT. The expression of mRNA for VEGF in DRG neurons after DRT showed a significant upregulation that was high even a year after the injuries. These data suggest a role for the semaphorins, neuropilins, VEGF, and J1 in the reactions after dorsal root lesions.
authors.affiliation: Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden; Helsa Företagshälsovård Östermalm, Stockholm, Sweden.
authors.forename: Tomas
authors.initials: T
authors.lastname: Lindholm
authors.affiliation: Department of Neuroscience, Karolinska Institutet , Stockholm , Sweden.
authors.forename: Mårten
authors.initials: M
authors.lastname: Risling
authors.affiliation: Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden; Hammersmith Hospital, University College London and Imperial College, London, UK; Department of Hand Surgery, Södersjukhuset, Stockholm, Sweden; Department of Clinical Science and Education, Karolinska Institutet, Södersjukhuset, Stockholm, Sweden.
authors.forename: Thomas
authors.initials: T
authors.lastname: Carlstedt
authors.affiliation: Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden; Department of Hand Surgery, Södersjukhuset, Stockholm, Sweden; Department of Clinical Science and Education, Karolinska Institutet, Södersjukhuset, Stockholm, Sweden.
authors.forename: Henrik
authors.initials: H
authors.lastname: Hammarberg
authors.affiliation: Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden; Department of Anesthesiology and Intensive Care, Västerås General Hospital, Västerås, Sweden.
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Wallquist
authors.affiliation: Department of Neuroscience, Karolinska Institutet , Stockholm , Sweden.
authors.forename: Staffan
authors.initials: S
authors.lastname: Cullheim
authors.affiliation: Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden; Department of Neuroscience, Section of Neurosurgery, Uppsala University, Uppsala, Sweden.
authors.forename: Mattias K
authors.initials: MK
authors.lastname: Sköld
keywords: DRG; VEGF; neuropilins; regeneration; rhizothomy; semaphorins