Changes in neurocan expression in the distal spinal cord stump following complete cord transection: a comparison between infant and adult rats.
The distal transected cords of infant rats are more permissive for axon extension than those of adults. To elucidate the biomolecular basis for this phenomenon, we examined the expression pattern of neurocan using semi-quantitative reverse transcription polymerase chain reaction and immunostaining in the distal cord of both adult and infant rats after transection. Neurocan is a chondroitin sulfate proteoglycan with well-documented axon growth-inhibitory properties in the central nervous system. Neurocan mRNA was up-regulated in the distal cord of adult rats shortly after transection, followed by a longer wide distribution of neurocan immunoreactivity (IR) in both neurons and astrocytes; by contrast, upregulation of neurocan mRNA was not seen in infant rats, although transient expression of neurocan IR was seen in neurons. Combined with the different regenerative capacity of infant and adult rats, the present results suggest that neurocan inhibits spinal cord regeneration.
Qi
Mei-Ling
ML
Section of Orthopaedic and Spinal Surgery, Department of Frontier Surgical Therapeutics, Division of Advanced Therapeutical Sciences, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, 113-8519 Tokyo, Japan.
Wakabayashi
Yoshiaki
Y
Enomoto
Mitsuhiro
M
Shinomiya
Kenichi
K
D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D011508:Chondroitin Sulfate Proteoglycans / Q000032:analysis / Q000096:biosynthesis*; D005786:Gene Expression Regulation / Q000502:physiology*; D037181:Lectins, C-Type; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000096:biosynthesis*; D058580:Neurocan; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000737:chemistry / Q000378:metabolism*; D013119:Spinal Cord Injuries / Q000378:metabolism*; D013904:Thoracic Vertebrae / Q000737:chemistry / Q000378:metabolism
D011508:Chondroitin Sulfate Proteoglycans; D037181:Lectins, C-Type; D009419:Nerve Tissue Proteins; D058580:Neurocan; D012333:RNA, Messenger; C076817:NCAN protein, human