Age-related changes in basic fibroblast growth factor-immunoreactive cells of rat substantia nigra.
Immunohistochemistry and computer-assisted image analysis were used to examine the age-related changes in bFGF-immunoreactivity in rat substantia nigra (SN). Distribution pattern, number, size and staining intensity of bFGF-immunoreactive (bFGF-ir) cells in pars compacta and pars reticulata of 3-, 12- and 26-month-old rats were compared. The overall distribution of bFGF-immunoreactivity was similar in the three age groups, but changes in the morphological appearance of bFGF-ir somata and processes occurred in aging. The results demonstrated a significantly reduced number of bFGF-ir cells in pars compacta (by 56.87%) and pars reticulata (by 30.4%) in 26-month-old rats compared to 3-month-old rats. The reduction of the cell number did not occur smoothly and equally in the two parts of SN. The quantitative analysis clearly indicated a significant decrease in the size of bFGF-ir neurons in pars compacta (by 18.1%) and pars reticulata (by 14.15%) of 26-month-old rats compared to 3-month-old rats. Compared to 3-month-old rats, a 19.77% and 17.83% increase in the staining intensity was observed in the remaining bFGF-ir neurons of pars compacta and pars reticulata, respectively in 26-month-old rats. Since there was no correlation between the decreased size and increased staining, it is most probable that the intensification of the staining intensity of bFGF-ir neurons was a compensatory response to the cell death.
Lolova
I S
IS
Institute of Physiology, Bulgarian Academy of Sciences, Sofia, Bulgaria.
Lolov
S R
SR
D000375:Aging / Q000378:metabolism*; D000818:Animals; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism*; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D008297:Male; D009562:Nissl Bodies / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013378:Substantia Nigra / Q000166:cytology / Q000378:metabolism*
D016222:Fibroblast Growth Factor 2