TY - JOUR
T1 - Increased vascular density and vitreo-retinal membranes accompany vascularization of the pigment epithelium in the dystrophic rat retina
AU - Caldwell, R. B.
AU - Roque, R. S.
AU - Solomon, S. W.
PY - 1989
Y1 - 1989
N2 - Observations of vascularization of the retinal pigment epithelium (RPE) and formation of vitreo-retinal membranes (VRMs) in Royal College of Surgeons (RCS) rats with inherited retinal dystrophy suggest that vascular proliferation occurs in this model. To test this hypothesis, we studied the progression of vascular changes in RCS and age-matched control rats using quantitative light microscope morphometry and electron microscopy. At 2 weeks, prior to photoreceptor degeneration, the dystrophic retina is comparable with the control. By 2 months, extensive degeneration of photoreceptor cells results in significant thinning of the dystrophic retina as compared with the control. Signs of vascular degeneration are evident at the electron microscope level - 'ghost' vessels consisting of acellular basal lamina surrounded by amorphous electron-dense material; degenerating endothelial cells and pericytes; and abnormal deposits of extracellular matrix (ECM) material around blood vessels. Vascular degeneration is accompanied by glial changes in the form of necrotic perivascular glial processes and abnormal ECM deposits among the altered Muller cell processes. At 2-4 months in the dystrophic retina, numbers of vessel profiles in dystrophic retinas are decreased as compared with controls. However, vascular degeneration is overshadowed by the formation of numerous capillary tufts within the RPE layer, which together with retinal thinning results in increased vessel density. Between 4-12 months, the retinal thickness diminishes further, vascularization of the RPE increases, vitreo-retinal membranes are formed, and vascular density increases. In summary, following an initial period of vascular degeneration, vascularization of the RPE is accompanied by an increase in retinal vessel density and by the formation of vitreo-retinal membranes.
AB - Observations of vascularization of the retinal pigment epithelium (RPE) and formation of vitreo-retinal membranes (VRMs) in Royal College of Surgeons (RCS) rats with inherited retinal dystrophy suggest that vascular proliferation occurs in this model. To test this hypothesis, we studied the progression of vascular changes in RCS and age-matched control rats using quantitative light microscope morphometry and electron microscopy. At 2 weeks, prior to photoreceptor degeneration, the dystrophic retina is comparable with the control. By 2 months, extensive degeneration of photoreceptor cells results in significant thinning of the dystrophic retina as compared with the control. Signs of vascular degeneration are evident at the electron microscope level - 'ghost' vessels consisting of acellular basal lamina surrounded by amorphous electron-dense material; degenerating endothelial cells and pericytes; and abnormal deposits of extracellular matrix (ECM) material around blood vessels. Vascular degeneration is accompanied by glial changes in the form of necrotic perivascular glial processes and abnormal ECM deposits among the altered Muller cell processes. At 2-4 months in the dystrophic retina, numbers of vessel profiles in dystrophic retinas are decreased as compared with controls. However, vascular degeneration is overshadowed by the formation of numerous capillary tufts within the RPE layer, which together with retinal thinning results in increased vessel density. Between 4-12 months, the retinal thickness diminishes further, vascularization of the RPE increases, vitreo-retinal membranes are formed, and vascular density increases. In summary, following an initial period of vascular degeneration, vascularization of the RPE is accompanied by an increase in retinal vessel density and by the formation of vitreo-retinal membranes.
UR - http://www.scopus.com/inward/record.url?scp=0024455782&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0024455782&partnerID=8YFLogxK
M3 - Article
C2 - 2477196
AN - SCOPUS:0024455782
SN - 0271-3683
VL - 8
SP - 923
EP - 937
JO - Current Eye Research
JF - Current Eye Research
IS - 9
ER -