Incorporation of plasma [14C]palmitate into the hypoglossal nucleus following unilateral axotomy of the hypoglossal nerve in adult rat, with and without regeneration.
Incorporation of plasma [14C]palmitate into the hypoglossal nucleus of the rat following transection, with and without regeneration of the hypoglossal nerve, was studied using quantitative autoradiography. The left hypoglossal nerve of 3-month-old, male Fischer-344 rats was transected using either: (1) an R-operation, which allowed nerve regeneration; or (2) a D-operation, in which regeneration was prevented. One to 84 days after axotomy, [14C]palmitate was injected intravenously and its rates of incorporation into stable structures of the left and right hypoglossal nuclei were measured at 4 h after injection. Following the R-operation, incorporation into the left hypoglossal nucleus was increased during and following axonal regeneration (up to 23% compared to control side), whereas incorporation was decreased 6-7% in the absence of regeneration, using the D-operation. The time courses of incorporation in both cases corresponded to histological changes, especially cell membrane changes following axotomy and suggest that [14C]palmitate incorporation reflects regenerative and degenerative neuronal changes associated with changes in lipid synthesis.
Yamazaki
S
S
Laboratory of Neurosciences, National Institute on Aging, Bethesda, MD 20892.
Noronha
J G
JG
Bell
J M
JM
Rapoport
S I
SI
D000818:Animals; D001345:Autoradiography; D001370:Axonal Transport; D002250:Carbon Radioisotopes; D006735:Horseradish Peroxidase; D007002:Hypoglossal Nerve / Q000378:metabolism / Q000502:physiology*; D008297:Male; D008526:Medulla Oblongata / Q000378:metabolism*; D009046:Motor Neurons / Q000502:physiology; D009416:Nerve Regeneration; D019308:Palmitic Acid; D010169:Palmitic Acids / Q000097:blood / Q000378:metabolism*; D051381:Rats; D011916:Rats, Inbred F344; D012016:Reference Values; D013997:Time Factors
D002250:Carbon Radioisotopes; D010169:Palmitic Acids; D019308:Palmitic Acid; D006735:Horseradish Peroxidase