Deposition of nidogens and other basement membrane proteins in the young and aging mouse retina.
OBJECTIVE
To determine the distribution of major basement membrane constituents, particularly nidogen 1 and 2, in young and aging mouse retinae.


METHODS
The specificity of antibodies against basement membrane proteins was ascertained by immunoblotting with proteins extracted from mouse retinae. The same antibodies were used in indirect immunofluorescence microscopy to localize basement membrane proteins in paraffin sections of retinae from 1-, 12- and 18-month-old C57BL/6 mice.


RESULTS
At a young age, laminin, perlecan and collagen IV were most abundant in Bruch's membrane. Later, the proteins were clearly detected in capillary basement membranes and the inner limiting membrane. In both of these basement membranes, a massive increase in protein amount was seen upon aging, whereas in Bruch's membrane the staining intensity was less drastically changed. Both nidogen 1 and 2 were present in vascular basement membranes and Bruch's membrane throughout the age periods studied. In the inner limiting membrane, the nidogens were more strongly expressed at higher ages, with an earlier and more extensive deposition of nidogen 1.


CONCLUSIONS
All major basement membrane constituents are present in the mouse retina, but the onset of deposition differs among the different proteins and between the various retinal basement membranes. In general, basement membrane protein deposition increases with age.
Kunze
Alexander
A
Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany.
Abari
Elizabeth
E
Semkova
Irina
I
Paulsson
Mats
M
Hartmann
Ursula
U
D000375:Aging / Q000502:physiology*; D000818:Animals; D001485:Basement Membrane / Q000378:metabolism; D015153:Blotting, Western; D016570:Bruch Membrane / Q000378:metabolism; D002135:Calcium-Binding Proteins; D015815:Cell Adhesion Molecules; D016326:Extracellular Matrix Proteins / Q000378:metabolism*; D019084:Fluorescent Antibody Technique, Indirect; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008856:Microscopy, Fluorescence; D012160:Retina / Q000378:metabolism*
D002135:Calcium-Binding Proteins; D015815:Cell Adhesion Molecules; D016326:Extracellular Matrix Proteins; D008562:Membrane Glycoproteins; C112846:Nid2 protein, mouse; C029967:nidogen