Retinal function and PKC alpha expression after focal laser photocoagulation

Dose-related changes in retinal function and PKC-alpha expression in rabbits on vigabatrin medication

“…Extensive PKC-alpha activation and eventually total depletion of enzyme activity has been observed in experiments with pharmacological interventions with phorbol esters and kainate [43]. Similar patterns of reactions are demonstrated in retinas exposed to ischemia [54] and focal laser photocoagulation [55]. Also in our study, retinas of VGB-treated rabbits demonstrated a redistribution of enzyme activity as well as a decreased number of PKC-alpha labeled rod bipolar cells.…”

Retinal Damage Profiles and Neuronal Effects of Laser Treatment: Comparison of a Conventional Photocoagulator and a Novel 3-Nanosecond Pulse Laser

“…69,70 The data presented in the current study indicate that there was a partial translocation of PKCa to the bipolar cell terminals subsequent to lasing, but this effect was detected only in the irradiated zone and was far less obvious than previously described. 32,35 Moreover, there was no evidence of a retina-wide downregulation of PKCa. Again, though, the laser settings used in the previous studies were significantly higher than in the present study, ranging from 120 to 700 mW, 32,35 which is likely the reason that the results demonstrated a greater effect on PKCa here.…”

“…32,35 Moreover, there was no evidence of a retina-wide downregulation of PKCa. Again, though, the laser settings used in the previous studies were significantly higher than in the present study, ranging from 120 to 700 mW, 32,35 which is likely the reason that the results demonstrated a greater effect on PKCa here. As rod bipolar cells receive electrical signals from rods, which are known to be killed in the current model, it is likely that an activation of PKCa would result from the loss of synaptic input to these cells.…”

“…32,35 Both translocation to bipolar cell terminals and subsequent downregulation are known to be associated with an activation of PKCa, 65 and this activation is known to be associated with injury paradigms in the retina. [66][67][68] Since PKCa plays a central role in cellular signal transduction and modulation of neurotransmitter release, 69 its activation is of interest to retinal functioning in general.…”

“…To date, histologic damage to the retina, in particular to photoreceptors, after conventional laser photocoagulation treatment has been well documented 15,[23][24][25][26][27][28][29][30][31] ; but while it is generally accepted that damage does not extend past the photoreceptors into the inner retina, detrimental effects have been observed. 27,[32][33][34][35][36] These data suggest that the inner neural retina can be affected in some manner by standard laser photocoagulation.…”