【Animal Modeling】-Comparison of the biological characteristics of the eyeball of two guinea pig strains and research on the mechanism of retinal myopia

  OBJECTIVE: To compare the biological characteristics of the eyeballs of Zmu-1:DHP and DHP guinea pigs, and to preliminarily explore the retina-related mechanism of spontaneous myopia in Zmu-1:DHP guinea pigs.

  Methods: By measuring the diopter, corneal curvature and axial length of Zmu-1:DHP inbred guinea pigs and DHP guinea pigs, the relative biological characteristics of the eyes of the two strains were compared, and the selected spontaneous myopia Zmu-1:DHP The guinea pigs and DHP guinea pigs were used for the observation of retinal structure and the expression of retinal signaling factor mRNA.

  Results: At the age of 3 weeks, the myopia rate of Zmu-1:DHP guinea pigs was 90.21%, and the myopia rate of DHP guinea pigs was 18.00%; from 4 to 12 weeks, with the increase of the age, the myopia degree and axial length of the left and right eyes of Zmu-1:DHP guinea pigs were greater than The corneal curvature of DHP guinea pigs is smaller than that of DHP guinea pigs, and there is a significant difference between the two (P<0.01). The observation of retinal tissue structure shows that Zmu-1: DHP guinea pigs have thinner outer nuclear layer, smaller cell volume, and fewer distribution numbers than DHP guinea pigs. The choroid atrophy and thinned, and no obvious pigment granules were found in the pigment epithelial cell layer, while a large number of brown-yellow pigment granules were distributed in the pigment epithelial cell layer of DHP guinea pigs. PCR results showed that Zmu-1: DHP guinea pig tyrosine hydroxylase (tyrosine hydroxylase) The expression of hydroxylase (TH) was decreased (P<0.01), the expression of tyrosine kinases (TK) was increased (P<0.01), the expression of inducible nitric oxide synthase (iNOS), neuronal NO synthase ( The expressions of neuronal nitric oxide synthase (nNOS), basic fibroblast growth factor (bFGF) and transforming growth factorβ (TGFβ) were enhanced (P<0.05), retinal dehydrogenation Although the expression of retinal dehydrogenase (RALDH) and aldehyde dehydrogenase (ALDH) was enhanced, the difference was not significant.

  Conclusion: Zmu-1:DHP guinea pigs have a high incidence of spontaneous myopia, which is axial myopia, and its molecular mechanism is related to the regulation of retinal myopia signaling factors.