Biochemical evidence for presence of dopamine beta-hydroxylase in rat retina.
Previously, we demonstrated immunocytochemically that certain phenylethanolamine N-methyltransferase neurons in the inner nuclear layer of rat retina contain other catecholamine synthesizing enzymes, including tyrosine hydroxylase and aromatic-L-amino acid decarboxylase but not dopamine beta-hydroxylase (DBH), the norepinephrine biosynthetic enzyme. In the present study by using a sensitive radioenzymatic assay for DBH we demonstrated the presence of DBH enzymatic activity in retinal extracts. Immunocytochemical studies, however, failed to demonstrate DBH-immunoreactive perikarya even in animals pretreated with colchicine, an inhibitor of axonal transport. Probably causes for these discrepant findings are discussed.
Park
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DH
Laboratory of Molecular Neurobiology, Cornell University Medical College, Burke Rehabilitation Center, White Plains, NY 10605.
Joh
T H
TH
Anwar
M
M
Ruggiero
D A
DA
D000818:Animals; D004299:Dopamine beta-Hydroxylase / Q000378:metabolism*; D007106:Immune Sera; D007124:Immunoenzyme Techniques; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values; D012160:Retina / Q000201:enzymology*; D012165:Retinal Ganglion Cells / Q000201:enzymology
D007106:Immune Sera; D004299:Dopamine beta-Hydroxylase