Histidine-like immunoreactivity in the rat retina.
OBJECTIVE
Histidine is an indispensable amino acid with an imidazole ring and it is a precursor of histamine, carnosine, and anserine. Histidine has been proposed to act as a neurotransmitter or neuromodulator in mammalian central nervous system (CNS), including retina. In this study, we report histidine-like immunoreactivity in the rat retina with the use of antibodies raised against histidine coupled to bovine serum albumin (BSA) with glutaraldehyde.


METHODS
In order to confirm the specificity of the antiserum toward histidine, immunodots were carried out. Only the histidine conjugate showed immunoreactivity. The rat retinas fixed with glutaraldehyde were used for immunocytochemistry.


RESULTS
Histidine immunoreactivity was identified in the ganglion cell layer (GCL), inner nuclear layer (INL), inner plexiform layer (IPL), and Müller cells of rat retina.


CONCLUSIONS
Histidine may be a precursor of histamine in the inner retina, and Müller cells may play some role in the metabolism of histidine.
Kusakari
Y
Y
Department of Ophthalmology, Tohoku University School of Medicine, Sendai, Japan.
Nishikawa
S
S
Ishiguro
S
S
Tamai
M
M
D000375:Aging / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn / Q000254:growth & development / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D006639:Histidine / Q000378:metabolism*; D007150:Immunohistochemistry / Q000379:methods; D011817:Rabbits; D051381:Rats; D017207:Rats, Sprague-Dawley; D012160:Retina / Q000254:growth & development / Q000378:metabolism*; D013194:Staining and Labeling; D014018:Tissue Distribution
D006639:Histidine