Abstract
Purpose: :
To investigate the effects of single and multiple intravitreal injections of bevacizumab on cellular viability of retinal ganglion cells (RGCs) in rats.
Methods: :
Ten rats were treated with intravitreal injection of 5 microliter of bevacizimab in their right eye. Left eyes were injected with the same volume of balanced salt solution (BSS), as control. Five rats received a single intravitreal injection and 5 rats had 3 injections, with 7 days time interval. Morphological evaluation was carried out by histological and immunohistochemical technique and TUNEL assay was performed in order to find out if some degree of apoptosis could occur on RGCs.
Results: :
Histology and immunohistochemistry showed bevacizumab-induced neuronal loss compared to control eyes, both after single and multiple injections. RGCs apoptosis was demonstrated to occur by TUNEL assay both after single and multiple treatments, compared with BSS-injected eyes. RGCs apoptosis was more massive after 3 injections, compared to single treatment.
Conclusions: :
Both single and multiple intravitreal injections of bevacizumab induce neuronal loss and RGCs apoptosis in rats. These effects seem to increase with repeated treatments. These results might be considered when intravitreal injection of bevacizumab are performed in humans for several retinal diseases.
Keywords: injection • retina: proximal (bipolar, amacrine, and ganglion cells) • apoptosis/cell death