Influence of aging on the calbindin-D-28k immunoreactive positive dopaminergic neurons in the substantia nigra pars compacta of rats.
We studied the relationship between aging and the vulnerability of substantia nigra pars compacta (SNc) calbindin-D-28k immunoreactive positive (CB+) dopaminergic (DA) neurons. Immunohistochemistry and cell counting were used to determine the number of CB+ DA neuron in aged rats (24 mon) compared to adult rats (5 mon). Furthermore, the expression of CB mRNA and protein levels in SN was studied by semi-quantitative RT-PCR and Western blotting. An 11% loss of CB+ DA neurons was detected in both the rostral (8.9%) and caudal (1.7%) segments but not in the intermedial segment of SNc in aged rats compared to adult rats (P<0.05). No difference was detected in CB mRNA and protein levels between aged and adult rats (P>0.05). These data suggest that expression levels of CB mRNA and protein may increase in the existing SNc DA neurons, which may compensate for the partial age dependent loss of CB+ DA neurons in the SNc.
Department of Neurobiology and Anatomy, Xuzhou Medical College, 84 West Huaihai Road, Xuzhou, Jiangsu, 221002, China.
Hong-mei
HM
Liu
Jin
J
Gao
Hui
H
Miao
Cheng-hua
CH
Xiao
Yu
Y
Sun
Xia
X
Du
Hong-hua
HH
Yuan
Hong-li
HL
Yu
Dian-shuai
DS
Gao
D000375:Aging / Q000378:metabolism*; D000818:Animals; D064026:Calbindins; D002452:Cell Count; D004298:Dopamine / Q000378:metabolism*; D007150:Immunohistochemistry; D008297:Male; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D064030:S100 Calcium Binding Protein G / Q000235:genetics / Q000378:metabolism*; D013378:Substantia Nigra / Q000166:cytology / Q000378:metabolism*
D064026:Calbindins; D012333:RNA, Messenger; D064030:S100 Calcium Binding Protein G; D004298:Dopamine