Immunohistochemistry of neuronal nitric oxide synthase and protein nitration in the striatum of the aged rat.
To ascertain the possible implications of the nitric oxide (NO*) producing system in striatal senescence, and by using immunohistochemistry and image-processing approaches, we describe the presence of the enzyme nitric oxide synthase (NOS), the NADPH-diaphorase (NADPH-d) histochemical marker, and nitrotyrosine-derived complexes (N-Tyr) in the striatum of adult and aged rats. The results showed neuronal NOS immunoreactive (nNOS-IR) aspiny medium-sized neurons and nervous fibres in both age groups, with no variation in the percentage of immunoreactive area but a significant decrease in the intensity and in the number of somata with age, which were not related to the observed increase with age of the striatal bundles of the white matter. In addition, NADPH-d activity was detected in neurons with morphology similar to that of the nNOS-IR cells; a decrease in the percentage of area per field and in the number of cells, but an increase in the intensity of staining for the NADPH-d histochemical marker, were detected with age. The number of neuronal NADPH-d somata was higher than for the nNOS-IR ones in both age groups. Moreover, N-Tyr-IR complexes were observed in cells (neurons and glia) and fibres, with a significant increase in the percentage of the area of immunoreaction, related to the increase of white matter, but a decrease in intensity for the aged group. On the other hand, we did not detect the inducible isoform (iNOS) either in adult or in aged rats. Taken together, these results support the contention that NADPH-d staining is not such an unambiguous marker for nNOS, and that increased protein nitration may participate in striatal aging.
Department of Experimental Biology, University of Jaén, Jaén, Spain.
María Luisa
ML
Del Moral
Francisco José
FJ
Esteban
Raquel
R
Hernández
Santos
S
Blanco
Francisco Javier
FJ
Molina
Esther
E
Martínez-Lara
Eva
E
Siles
Gloria
G
Viedma
Alharilla
A
Ruiz
Juan Angel
JA
Pedrosa
María Angeles
MA
Peinado
D000375:Aging / Q000378:metabolism*; D000818:Animals; D015415:Biomarkers; D003342:Corpus Striatum / Q000201:enzymology*; D007150:Immunohistochemistry; D009252:NADPH Dehydrogenase / Q000378:metabolism*; D009412:Nerve Fibers / Q000201:enzymology; D009419:Nerve Tissue Proteins / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000032:analysis* / Q000096:biosynthesis; D052248:Nitric Oxide Synthase Type I; D051381:Rats; D017208:Rats, Wistar
D015415:Biomarkers; D009419:Nerve Tissue Proteins; D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I; C496322:Nos1 protein, rat; D009252:NADPH Dehydrogenase