The use of progenitor cell/biodegradable MMP2-PLGA polymer constructs to enhance cellular integration and retinal repopulation.

The inability of the adult mammalian retina to regenerate can be partly attributed to the expression of injury-induced inhibitory extracellular matrix (ECM) and cell adhesion molecules. In particular, photoreceptor degeneration stimulates deposition of the inhibitory ECM proteins neurocan and CD44 at the outer limits of the dystrophic retina, where they act as a barrier against cellular migration and axonal extension. We have previously shown that degradation of these molecules, via induction of MMP2, promotes host-donor integration and retinal repopulation following transplantation.

Müller cell activation, proliferation and migration following laser injury.

Purpose: Müller cells are well known for their critical role in normal retinal structure and function, but their reaction to retinal injury and subsequent role in retinal remodeling is less well characterized. In this study we used a mouse model of retinal laser photocoagulation to examine injury-induced Müller glial reaction, and determine how this reaction was related to injury-induced retinal regeneration and cellular repopulation.

Methods: Experiments were performed on 3-4-week-old C57BL/6 mice.

Dissociations of the medial and lateral perforant path projections into dorsal DG, CA3, and CA1 for spatial and nonspatial (visual object) information processing.

Medial perforant path plasticity can be attenuated by 2-amino-5-phosphonovaleric acid (APV) infusions, whereas lateral perforant path plasticity can be attenuated by naloxone infusions. The present experiment was designed to evaluate the role of each entorhinal efferent pathway into the dorsal hippocampus for detection of spatial and nonspatial (visual object) changes in the overall configuration of environmental stimuli. Dorsal dentate gyrus infusions of either APV or naloxone attenuated detection of a spatial change, whereas only naloxone infusions disrupted novel object detection.