Phenylephrine eye drops

Refraction and axial length were measured at the initial (3-week-old) and the end (6-week-old) stage of the myopic induction using an infrared photorefractor (Steinbeis Transfer Center, Germany) and a SD-OCT system (Envisu R4310, Leica, Germany). All measurements were performed under mydriasis by 0.5% tropicamide and 0.5% phenylephrine eye drops (Santen, Japan), and general anesthesia by MMB. The refractive error values were averaged with 100 times of the measurement in a continuous data trace. The axial length was determined from the anterior corneal surface to the retinal pigment epithelium along the corneal vertex reflection. Since the choroidal thickness was considered to vary by the location, the choroidal area distant from the disc was calculated to compare the mean choroidal thickness. The area of the circumference at 0.5 mm from the disc circled at the border of the retinal pigment epithelium and the posterior surface of the choroid^{60 (link)} was quantified with ImageJ (National Institutes of Health, Bethesda, USA) (Supplementary Fig. 1). Choroidal thickness is led by the formula; the area is divided by the circumference. The corneal curvature radius was measured by an infrared keratometer (Steinbeis Transfer Center, Germany).

8-week-old C57BL/6 mice were used for subretinal injection. Pupils were first dilated with 0.5% tropicamide and 0.5% phenylephrine eye drops (Santen Pharmaceutical). Mice were then anesthetized with a mixture of zoletil (60 mg/kg) and xylazine (10 mg/kg). A small hole at the slight posterior to the limbus was punctured with a sterile 31 G 1/2 needle. One microliter of AAV virus and vehicle was subretinally injected slowly through the hole using a Hamilton syringe with a 33 G blunt needle. The working dose of AAV in the retina is 3E9 vg/eye. Eyes with severe hemorrhage or damage were excluded from further study.

ERGs were recorded 1 day before and 1 day after light-induced damage and at 2, 4, and 8 weeks after retinal cell transplantation. According to published methods [40 (link), 70 (link)], rats were anesthetized with amine (100 mg/kg) and xylazine (12 mg/kg) under dim red light after dark adaptation for 12 h. Rat pupils were then dilated with phenylephrine eye drops (Santen Pharmaceutical Co., Ltd., Japan). Corneal ERG responses were recorded from both eyes simultaneously with gold wire loops. Carboxymethylcellulose sodium eye drops (Allergan, Ireland) were frequently applied to the cornea to prevent dehydration and to allow electrical contact with the recording electrode. Two needle electrodes inserted under the outer layer served as the reference electrodes, whereas the other electrode placed in the tail served as a “ground”. Amplification was at a 0.1–500 Hz band pass without notch filtering, and stimulus presentation and data acquisition were provided using a RETIscan system (Roland, Germany).