RT Journal Article
SR Electronic
T1 Phenylethanolamine N-methyltransferase-containing neurons in rat retina: immunohistochemistry, immunochemistry, and molecular biology
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 1108
OP 1113
DO 10.1523/JNEUROSCI.06-04-01108.1986
VO 6
IS 4
A1 DH Park
A1 G Teitelman
A1 MJ Evinger
A1 JI Woo
A1 DA Ruggiero
A1 VR Albert
A1 EE Baetge
A1 VM Pickel
A1 DJ Reis
A1 TH Joh
YR 1986
UL http://www.jneurosci.org/content/6/4/1108.abstract
AB We sought to characterize in detail neurons in rat retina that contain phenylethanolamine N-methyltransferase (PNMT), the epinephrine biosynthetic enzyme. Cell bodies and processes of PNMT-containing neurons in retina were identified by immunohistochemistry. The coexistence of other catecholamine biosynthetic enzymes in the same cells was also investigated. Biochemical, molecular biological and immunochemical methods were applied to determine whether retinal PNMT is similar to the adrenal enzyme, since regulation of PNMT in retina and adrenal appears to be different. The results show that there are two types of PNMT-containing cells: those containing PNMT exclusively and those containing PNMT with two other catecholamine-synthesizing enzymes, tyrosine hydroxylase (TH) and aromatic L-amino acid decarboxylase (AADC), but not dopamine beta-hydroxylase (DBH). PNMT- only cell bodies are localized in the inner nuclear layer (INL) and the ganglion cell layer (GCL). Their processes are observed in outer and inner strata of the inner plexiform layer (IPL). Only a small fraction of PNMT neurons in INL also contain TH and AADC. These cells send their processes to the adjacent stratum of the IPL. Antibodies to bovine adrenal DBH, however, fail to localize DBH in any rat retinal cells. Immunochemical titration shows that PNMT from both retina and adrenal gland has the same immunoreactivity. Furthermore, a PNMT-cDNA probe hybridizes equally with PNMT-mRNA isolated from both the retina and the adrenal gland. These results indicate that PNMT is identical in these tissues.