Unlike mammals, zebrafish have the ability to regenerate their central nervous system. We study the regeneration process that takes place in zebrafish retinas after their photoreceptors have been damaged. This regeneration requires an inflammatory response, mediated cells called microglia. Midkine-a is a cytokine required for microglia to phagocytose dying photoreceptors, a key step in regulating inflammation. In the absence of midkine-a, microglial phagocytosis fails. This project tested the hypothesis that the putative midkine-a and microglia-specific receptor, Lrp1ab, is also required for the microglial phagocytosis of dying photoreceptors. After creating a photoreceptor lesion in a Lrp1ab mutant (-/-) fish, we investigate how the microglia phagocytosis process is affected without the presence of the Lrp1ab receptor by staining for microglia. To study the effect even further, we go beyond just microglia and also stain for proliferating cells. The results of the staining revealed the nature of microglia and proliferation cells, however, some unexpected changes to the morphology of the microglia were also observed.