Dexamethasone up-regulates mRNA for Na+,K(+)-ATPase in some spinal cord neurones after cord transection.
We have studied the effects of spinal cord transection and of dexamethasone (DEX) treatment on mRNA biosynthesis of the Na+, K(+)-ATPase, a key enzyme necessary for neurotransmission, membrane repolarization and nutrient uptake in the CNS. In situ hybridization analysis revealed a significant reduction in mRNA for the alpha 3 catalytic subunit of the enzyme in medium and large size ventral horn neurones (1000-2300 microns2) but not in small cells (1000 microns2) 24 h after spinal cord transection. DEX treatment significantly reversed the transection effect in medium and large size neurones. It is suggested that up-regulation of mRNA expression for Na+,K(+)-ATPase may constitute an important mechanism by which glucocorticoids help to re-establish neuronal function after spinal cord injury.
Gonzalez
S
S
Faculty of Medicine, University of Buenos Aires, Argentina.
Grillo
C
C
Gonzalez Deniselle
M C
MC
Lima
A
A
McEwen
B S
BS
De Nicola
A F
AF
D000818:Animals; D003907:Dexamethasone / Q000494:pharmacology*; D005938:Glucocorticoids / Q000494:pharmacology*; D008297:Male; D009416:Nerve Regeneration / Q000187:drug effects; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D012333:RNA, Messenger / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D000254:Sodium-Potassium-Exchanging ATPase / Q000235:genetics*; D013119:Spinal Cord Injuries / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D015854:Up-Regulation
D005938:Glucocorticoids; D012333:RNA, Messenger; D003907:Dexamethasone; D000254:Sodium-Potassium-Exchanging ATPase