The study of pharmacokinetics of verapamil in vitreous following subconjunctival administration in an experimental model of PVR

Objective: To study the pharmacokinetic parameters of verapamil in vitreous following subconjunctival administration. Methods: An experimental model of traumatic proliferative vitreoretinopathy was produced in pigment rabbits，which received subconjunctival verapamil injection.The concentrations of verapamil in vitreous at various times were determined by a reversed- phase HPLC， and the pharmacokinetic parameters were analyzed by 3P87.Results: The pharmacokinetic parameters were as follows: lagtime=(12.6±4.4)min，T (peak)=(2.10±0.84)h，Cmax =(17.65±4.64(g)/ml，Ka=(1.34± 0.26)/h，t_1/2(Ka)=(0.54±0.16)h，Ke=(0.09±0.03)/h，t_1/2(Ke)=(7.29(1.46)h，AUC=(208.07(40.22±μg/(ml· h).Conclusion: Verapamil penetrates into the vitreous following subconjunctival administration and reaches potentially therapeutic concentrations for 24hours.The results provide the basis of subconjunctival verapamil for the treatment of PVR.