Abstract
Purpose: :
To study the ocular phenotype of mice that lack Haptoglobin (Hpko) and investigate whether these changes correlate with the expression of C-maf. C-maf is known to be expressed in embryonic life and to be involved in the development of the lens and anterior segment.
Methods: :
Hpko mice and wild type(WT)littermates were histological investigated at embryonic day(E)12,15 and 18 and postnatal day(P)1,4 and 21. The expression of C-maf was studied at mRNA level by rt-PCR. C-maf expression in eyes was compared in adult mice between clinically blind versus not-blind Hpko and WT mice and in embryos at E12,between offspring from clinical blind versus not-blind Hpko mothers.
Results: :
Eyes of Hpko mice were histological normal at E12 compared with WT mice. At P1 eyes of Hpko mice were significantly smaller (mean 29%); in 55% of mice the lens was not yet separated form the cornea. At P21 12% of the eyes from Hpko mice still showed contact between lens and cornea; anterior senychiae were present in 42% of the eyes, whereas these structural abnormalities were never observed in WT eyes.The ocular C-maf mRNA expression at E12 was significantly lower in Hpko embryos as compared to WT embryos (P<0.05). C-maf expression levels in eyes of Hpko non-blind mothers were intermediate.
Conclusions: :
Haptoglobin knockout mice exhibit developmental disorders that are similar to those observed in developmental glaucoma. There is a delay in development of the anterior segment structures, which start during late embryonic life and continue after birth. C-maf expression is diminished at E12 and this may be linked to the aberrant anterior chamber development.
Keywords: anterior segment • genetics • development