Quantitative analyses of mRNA and protein levels of neurotrophin-3 in the rat retina during postnatal development and aging.
OBJECTIVE
In this study, we sought to elucidate changes in the levels of neurotrophin-3 (NT-3) in the rat retina throughout postnatal development and aging.


METHODS
We demonstrated NT-3 localization in the retina by immunohistochemistry. Protein and mRNA levels of NT-3 were quantified by enzyme-linked immunosorbant assay and semiquantitative reverse transcriptase-polymerase chain reaction, respectively. NT-3 protein levels were assayed in the various regions of the central nervous system. Age-associated changes in protein and mRNA levels of NT-3 in the retinas were assessed.


RESULTS
NT-3-immunoreactivity localized in the ganglion cell layer, inner nuclear layer, and outer nuclear layer. NT-3 content in the retina was relatively high in the examined regions of the central nervous system. Retinal NT-3 protein levels decreased after eye opening, whereas mRNA levels were constant. Both mRNA and protein levels of NT-3 in the retinas of aged animals remained constant.


CONCLUSIONS
Our observations suggest that NT-3 regulation in the retina is independent of increasing visual stimuli after eye opening. Stable expression of NT-3 in the adult retina suggests a possible role in the maintenance of the retinal environment throughout later life.
Division of Ophthalmology and Visual Science, Graduate School of Medical and Dental Sciences, Niigata University, Niigata 951-8585, Japan. hanpen@med.niigata-u.ac.jp.
Masaaki
M
Seki
Takeo
T
Fukuchi
Takayuki
T
Tanaka
Hiroyuki
H
Nawa
Nobuyuki
N
Takei
Haruki
H
Abe
D000375:Aging / Q000502:physiology*; D000818:Animals; D004797:Enzyme-Linked Immunosorbent Assay; D018507:Gene Expression Regulation, Developmental; D007150:Immunohistochemistry; D008297:Male; D020933:Neurotrophin 3 / Q000235:genetics* / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012160:Retina / Q000254:growth & development / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D020933:Neurotrophin 3; D012333:RNA, Messenger