Molecular and Cellular Regulations in the Development of the Choroidal Circulation System

Disorders in the development and regulation of blood vessels are involved in various ocular disorders, such as persistent hyperplastic primary vitreous, familial exudative vitreoretinopathy, and choroidal dystrophy. Thus, the appropriate regulation of vascular development is essential for healthy ocular functions. However, regulation of the developing choroidal circulation system has not been well studied compared with vascular regulation in the vitreous and the retina. The choroid is a vascular-rich and uniquely structured tissue supplying oxygen and nutrients to the retina, and hypoplasia and the degeneration of the choroid are involved in many ocular disorders. Therefore, understanding the developing choroidal circulation system expands our knowledge of ocular development and supports our understanding of ocular disorders. In this review, we examine studies on regulating the developing choroidal circulation system at the cellular and molecular levels and discuss the relevance to human diseases.