ABSTRACT
Objective To investigate the effects of amphiregulin antibody on the axial length,diopter and posterior sclera thickness in eyes of bilateral lens-induced myopic guinea pigs.Methods A total of 60 healthy three-colored short-hair guinea pigs were randomly divided into 5 groups:myopic model group,low dose group,medium dose group,high dose group and normal control group,12 rats in each group,and both eyes of the guinea pigs in the former four groups were induced by-10 D lens,while the normal group did not make any treatment.After wearing of goggles for 2 weeks,the right eyes of guinea pigs were intravitreally administrated with 5 μg,10 μg,20 μg anphiregulin antibody for the low,medium and high dose group,respectively.At the same time,the left eyes of these groups were given the same dose of Ringer' s buffer (buffer group).Continuous wearing of the lenses before and after injection of antibody was allowed.Diopter and axial length of guinea pigs were measured before wearing of the lenses,2 weeks after wearing lenses and 5 weeks after the experiment (after 3-times injections of antibody).Moreover,the thicknesses of retina,choroid and sclera in the posterior pole were detected by PAS staining.Finally,the expression of amphiregulin and EGFR mRNA and protein was detected by real time quantitative PCR and immunofluorescence.Results After 2 weeks of lens induction,the axial length of the myopic model group increased,but the diopter decreased when compared with the normal control group,and the differences were statistically significant (both P ＜ 0.05).Compared with the buffer group,after intravitreal injection of amphiregulin antibody,the axial length in the low,medium,and high dose groups decreased,while the diopter increased,and the scleral thickness at the posterior pole increased significantly in a dose-dependent manner,with statistically significant differences (all P ＜ 0.05).However,there was no significant change in retinal thickness at the posterior pole of all groups.Real-time quantitative PCR and immunofluorescence showed the expression of amphiregulin mRNA and protein in the retina was upregulated the myopic model group and buffer group,but downregulated in the high,medium,and low dose groups.Furthermore,when compared with the buffer group,the expression level of epidermal growth factor receptor in the retina of the low dose group was decreased (t =2.606,P =0.022),but there was no significant difference in the other groups.Conclusion After injection of amphiregulin antibody into the eyes of bilateral lens-induced myopic guinea pigs,the diopter increases,but the axial length is significantly shortened,and the posterior sclera is thickened,which may involve a decrease in the expression of amphiregulin.
ABSTRACT
· AIM:To compare the effect of fixation and select the optimal fixation solution and condition for PAS staining of guinea pig eyes among three different fixation solution:4％ paraformaldehyde solution,4％ glutaraldehyde solution and Davidson solution.· METHODS:Totally 30 healthy guinea pigs were divided into 6 groups:Group Ⅰ-Ⅱ were fixed in 4％ paraformaldehyde solution and 4％ glutaraldehyde solution for 24h,respectively;Group Ⅲ-Ⅴ were fixed in Davidson solution for 3,6 and 24h,respectively;and Group Ⅵ were fixed in Davidson solution for 3h and then transferred into 10％ neutral formaldehyde solution for 48h.All groups were sectioned by routine section method and undergone PAS staining,and then observed by light microscope.· RESULTS:It was found that the group which was fixed by Davidson solution for 3h,remained the most complete structure for PAS staining (Group Ⅲ).While the effect of fixation for the group which was transferred into 10％ neutral formaldehyde solution for preserving for 48h after fixing in Davidson solution for 3h was also acceptable for PAS staining (Group Ⅵ).The retinal cells remained clear and in order for both groups which was mentioned above.· CONCLUSION:The best fixation condition for PAS staining for eyes of guinea pigs is fixation in Davidson solution for 3h among these fixation conditions,while it is also suitable to transfer the eyes into neutral formaldehyde solution after fixing in Davidson solution for 3h for preserving for long periods,which is not severely reduced the effect of fixation for PAS staining.