Journal of Neuroscience, Vol 15, 1735-1740, Copyright © 1995 by Society for Neuroscience
Aging-related changes in rat striatal D2 receptor mRNA-containing neurons: a quantitative nonradioactive in situ hybridization study
L Zhang, A Ravipati, J Joseph and GS Roth
Molecular Physiology and Genetics Section, NIA/NIH, Baltimore, Maryland 21224.
In situ hybridization of a digoxigenin-labeled oligonucleotide probe
combined with computer-assisted image assessment was used to directly
visualize D2 receptor mRNA-containing neurons in rat striata, and quantify
age-related changes in the sizes and relative mRNA content of these
neurons. It was found that: (1) numbers of D2 mRNA-containing neurons
appear to decrease in striata of aged rats, (2) relative amounts of D2
receptor mRNA decrease in striatal neurons of aged rats, and (3) neurons of
all sizes appear to be lost, with the greatest absolute decrease in those
smaller than 90 microns 2. These data confirm the well documented
age-associated loss of D2 dopamine receptors, and further suggest that both
neuronal death and reduced transcription contribute to this decrement.