OBJECTIVE: To investigate the distribution, changes and a possible role for retinal dopamine transporter (DAT) in experimental myopia in chickens. METHODS: Two-day-old chickens were divided into four groups. Chicken eyes were fitted with lenses of -10D,-20D and translucent goggles unilaterally. Normal eyes were used as controls. After 3 wk, all chickens were given an intramuscular injection of (125)I-beta-CIT 2beta-carbomethoxy-3beta-(4-iodophenyl)tropane and sacrificed two hours post injection. Retinal pigment epithelium (RPE) and the neural retina were obtained together or RPE was dissected out from the neural retina. Radioactive DAT from each specimen was assayed by gamma-counter. RESULTS: Retinal DAT was detected in RPE specimens rather than in the neural retina in all eyes. Radioactive DAT in myopic eyes was higher, compared with control eyes. CONCLUSIONS: Retinal DAT is mainly located in the RPE and may be involved in the formation of lens induced myopia (LIM) and form deprivation myopia (FDM). These methods may provide a new approach for further studying the role of the dopamine system in experimental myopia.
