Somatostatin analogs inhibit neonatal retinal neovascularization

The goal of this study was to determine the effect of two somatostatin analogs, Woc4D and octreotide, on oxygen induced retinopathy in the mouse. Oxygen induced retinopathy was produced in C57BL6 mice. Octreotide and Woc4D were administered from post-natal day 12-16. Retinopathy was assessed by a retinal scoring system utilizing fluorescein perfused retinal whole mounts. Animals treated with Woc4D and octreotide, respectively, had median retinopathy scores of 4(3,5) [median(25th, 75th quartile)] with P = 0.01 and 3.5(2.9,4.3) with P = 0.01 compared to oxygen and sham treated oxygen animals with scores of 6.6(5.3,8.5) and 7.4(5.8,8.6), respectively. Woc4D and octreotide treated animals had decreased blood vessel tufts and decreased extra-retinal neovascularization when compared to oxygen treated animals. Pituitary growth hormone (GH) mRNA expression was increased 8.3-fold by Woc4D treatment and 106-fold by oxygen exposure, and GH and mRNA was markedly reduced by Woc4D as well as octreotide. Growth as measured by animal weight was unaffected by either treatment. Woc4D and octreotide inhibited retinal neovascularization in an equally effective manner in the mouse model of oxygen induced retinopathy.