Expression of neuropeptide substance P in corneal tissues after PRK and LASIK

Objective To quantitatively detect the expression of neuropeptide substance P(SP)in cornea after photorefractive keratectomy(PRK)and laser in-situ keratomileusis(LASIK),and to discuss the effect of SP during corneal healing after PRK.Methods LASIK was performed on the right eyes and PRK on the left eyes in twelve rabbits,all surgery were carried with-4.00 D myopia,the lighting diameter of artherectomy was 6 mm,and the depth of artherectomy was 80 μm.The corneal tissues were taken at 1 month after ablation,the total RNA was made,and cDNA was reverse transcribed,the expressive level of SP was detected by quantitative RT-PCR.Results The expressive levels of SP in cornea varied after PRK and LASIK,the mean relative content of SP mRNA after PRK was 0.024 120±0.002 681(SP/β-actin),which after LASIK was 0.002 500±0.000 353(SP/β-actin),the former was higher than the latter,there was significant difference(P=0.000).Conclusion The expressive level of SP in cornea varies after PRK and LASIK,the SP expression increases in the corneal tissue after PRK,which indicates that SP may involved in regulating the process of corneal healing after PRK.