Target-determined expression of alpha3 isoform of the Na+,K+-ATPase in the somatic nervous system of rat.
Factors that determine the differential expression of isoforms of Na(+),K(+)-ATPase in the nervous system of vertebrates are not understood. To address this question we studied the expression of alpha(3) Na(+),K(+)-ATPase in the L5 dorsal root ganglia (DRG) of developing rat, the normal adult rat, and the adult rat after peripheral axotomy. During development, the first alpha(3) Na(+),K(+)-ATPase-positive DRG neurons appear by embryonic day 21. At birth, the L5 DRG have a full complement (14 +/- 2%) of these neurons. By 15 days after sciatic nerve transection in adult rat, the number of alpha(3) Na(+),K(+)-ATPase-positive DRG neurons and small myelinated L5 ventral root axons decreases to about 35% of control counts. These results combined with data from the literature suggest that the expression of alpha(3) Na(+),K(+)-ATPase by rat somatic neurons is determined by target-muscle spindle-derived factors.
Romanovsky
Dmitry
D
Department of Anesthesiology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA.
Light
Kim E
KE
Walker
James
J
Dobretsov
Maxim
M
D000818:Animals; D019771:Axotomy; D003714:Denervation; D005260:Female; D005727:Ganglia, Spinal / Q000166:cytology / Q000196:embryology / Q000201:enzymology*; D005786:Gene Expression Regulation / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D007527:Isoenzymes / Q000378:metabolism; D008297:Male; D008465:Mechanoreceptors / Q000196:embryology / Q000201:enzymology; D009046:Motor Neurons / Q000201:enzymology; D009474:Neurons / Q000201:enzymology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012584:Sciatic Nerve / Q000166:cytology / Q000201:enzymology; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*
D007527:Isoenzymes; D000254:Sodium-Potassium-Exchanging ATPase