The Effect Of Different Light Intensity On The Development Of Diopter And The Expression Of BMP-2 In Sclera Of Guinea Pig

Objective:To observe the effect of different light intensity on the development of diopter and the expression of BMP-2 in sclera of guinea pig with myopia induced by negative lens.Methods:30 SPF grade tricolor guinea pigs were randomly divided into 10 strong light group,10 normal light group and 10 weak light group.The light intensity of the three groups were:10000 lux in the strong light group,500 lux in the normal light group,and 5 lux in the weak light group.The right eye of each guinea pig was intervened with-7.00 D lens,and the left eye was self contrast eye.Before and after the light and lens induction,the biological parameters of both sides of all guinea pigs’ eyes were measured,including(diopter,axial length).The dioptric state of guinea pigs’ eyes was detected by strip light detection and optometry with A-scan,and the axial length of guinea pigs’ eyes was measured by A-scan.The refractive status and axial length of the eyes were measured in the second week,the fourth week and the sixth week.At the end of the sixth week of the experiment,the guinea pigs were killed after measuring the data,the eyes of guinea pigs were taken out,the sclera tissues were separated,the tissue proteins were extracted,and the sclera BMP-2 of guinea pigs was quantitatively analyzed by Western blot.Results:there was no significant difference in diopter and ocular axis between the three groups(P>0.05).With the extension of light time,the axial length of the eyes of the three groups of guinea pigs were gradually extended,while the diopter was gradually reduced.At each time point after light exposure,due to the intervention of the right eye lens of all guinea pigs,there was no significant difference in the biological parameters of both eyes in the three groups(P>0.05);there was statistical significance in the biological parameters of both eyes in the weak light group and the normal light group(P<0.05).Due to different light intensity,the biological parameters of the three groups were statistically significant(P.The expression of BMP-2 protein in the sclera of guinea pig was quantitatively analyzed by Western blot.There was no significant difference among the three groups(P>0.05),the strong light group and the double eyes(P>0.05).There was significant difference between the weak light group and the normal light group(P<0.05).Among the three groups,the expression of BMP-2 protein in both eyes of the strong light group,the weak light group and the normal light group was statistically significant(P<0.05),while the expression of BMP-2 protein in both eyes of the weak light group and the normal light group was not statistically significant(P>0.05).Conclusion:1.Under the strong light stimulation,the emmetropia process of diopter development in guinea pig eyes slows down.The strong light is the protective factor of myopia.2.BMP-2 was highly expressed in the sclera of both eyes of the guinea pig in the strong light group.BMP-2 may play an important role in the sclera remodeling of the guinea pig,thus delaying the emmetropia process.