HTR5A and myopia: Similar to FDM, FLM displayed significant increase in the concentrations of 5-HT in the retina, vitreous body and RPE, up-regulation of 5-HT2AR in the retina and general decrease in the concentrations of NE and E, which further suggests the involvement of 5-HT, 5-HT2AR, NE and E in the myopia development.