title: Changes in NADPH-diaphorase neurons of the rat laterodorsal and pedunculopontine tegmental nuclei in aging.
abstract: The aim of the present study was to compare the morphological pattern and the quantitative parameters of nitric oxide (NO)-containing neurons in the laterodorsal (LTD) and pedunculopontine (PPN) tegmental nuclei of 3-, 12- and 26-month-old rats. NADPH-diaphorase (NADPH-d) histochemical reaction, as a marker of the cholinergic neurons in the two mesopontine nuclei, and computer-assisted image analysis were used. The relationships between the neurons stained for NADPH-d and choline acetyltransferase (ChAT) were examined using a double-labelling procedure. The results demonstrated only occasional ChAT positive somata that did not exhibit NADPH-d staining. The volume of the LTD and PPN and the number of NADPH-d neurons remained unaltered with advancing age. However, ANOVA demonstrated a significant effect of age and level on the cross-sectional areas, maximum diameters and staining intensity of NADPH-d somata in the LTD and PPN. The three parameters were reduced in 26-month-old rats compared to 3-month-old rats. The changes in the morphological appearance of NADPH-d somata and processes as well as the quantitative analysis pointed to age-related neuronal atrophy. It was accompanied by hypertrophy of some neighbouring neurons, suggesting a compensatory mechanism which would counteract the degenerative changes. The age-dependent alterations in the LTD and PPN were rather similar.
authors.affiliation: Institute of Physiology, Bulgarian Academy of Sciences, Sofia, Bulgaria.
authors.forename: I S
authors.initials: IS
authors.lastname: Lolova
authors.forename: S R
authors.initials: SR
authors.lastname: Lolov
authors.forename: D E
authors.initials: DE
authors.lastname: Itzev
mesh_terms: D000375:Aging / Q000378:metabolism* / Q000473:pathology; D000704:Analysis of Variance; D000818:Animals; D001284:Atrophy; D048429:Cell Size; D002795:Choline O-Acetyltransferase / Q000032:analysis; D004396:Coloring Agents; D006651:Histocytochemistry; D007091:Image Processing, Computer-Assisted; D008297:Male; D009252:NADPH Dehydrogenase / Q000032:analysis*; D009474:Neurons / Q000201:enzymology* / Q000473:pathology; D009569:Nitric Oxide / Q000032:analysis*; D051381:Rats; D017208:Rats, Wistar; D013053:Spectrophotometry; D013681:Tegmentum Mesencephali / Q000166:cytology / Q000201:enzymology* / Q000473:pathology
chemical_list: D004396:Coloring Agents; D009569:Nitric Oxide; D009252:NADPH Dehydrogenase; D002795:Choline O-Acetyltransferase