Comparison of the substance P- and dynorphin-containing projections to the substantia nigra: a radioimmunocytochemical and biochemical study.
A series of knife cuts were made in the striatonigral pathway and changes in dynorphin B (Dyn) and substance P (SP) input to the substantia nigra were examined using radiolabeled antibodies and radioimmunoassay (RIA). Cryostat cut sections were incubated with primary antibody followed by a secondary antibody labeled with 125I. Apposition of the radiolabeled sections to LKB Ultrofilm generated an image that was qualified by computerized optical densitometry. The striatonigral system served as a model system for comparing the quantitative capabilities of radioimmunocytochemistry with RIA. The results indicated a strong correlation between optical densitometry measurements and RIA for both Dyn (r = 0.97) and SP (r = 0.98) antisera. This suggests that radioimmunocytochemistry may be used for quantitative, as well as, qualitative descriptions of the distribution of tissue antigens. Knife cuts separating the rostral caudate putamen from the substantia nigra resulted in less than 40% depletion of dynorphin and substance P in the nigra pars reticulata, leaving the levels of both peptides relatively unchanged in the pars lateralis. More caudal knife cuts resulted in progressively greater depletions of both peptides in the pars reticulata and pars lateralis.
S
S
McLean
M J
MJ
Bannon
N
N
Zamir
C B
CB
Pert
D000818:Animals; D000906:Antibodies; D000936:Antigen-Antibody Complex; D003720:Densitometry; D004399:Dynorphins / Q000032:analysis*; D007457:Iodine Radioisotopes; D008297:Male; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains; D013373:Substance P / Q000032:analysis*; D013378:Substantia Nigra / Q000032:analysis* / Q000166:cytology
D000906:Antibodies; D000936:Antigen-Antibody Complex; D007457:Iodine Radioisotopes; D013373:Substance P; D004399:Dynorphins