Nontoxic concentration of antibiotics for intravitreal use--evaluated by human in-vitro ERG.

The effects of penicillin G (PC-G) sodium, procaine PC-G, cloxacillin sodium (MCIPC), disodium sulbenicillin (SBPC), cefazolin sodium (CEZ), gentamicin sulfate (GM) and fosfomycin sodium (FOM) on the electroretinogram (ERG) of the human in-vitro eye-cup were studied. The oscillatory potentials (OPs) were selectively and greatly suppressed by 1.0 mM PC-G sodium. The OPs and c-wave were suppressed by 0.85 mM procaine PC-G. The b-wave and OPs were slightly suppressed by 1.0 mM MCIPC. The a-wave, b-wave, OPs and c-wave were not deteriorated by 1.0 mM SBPC. The OPs appeared to be selectively suppressed by 1.0 mM CEZ. The b-wave was suppressed and the peak latencies of the OPs were delayed by 184 micrograms/ml (approximately 0.4 mM) GM. The amplitudes of the a-wave and c-wave were slightly enhanced and their peak latencies were slightly delayed by 184 micrograms/ml GM. The a-wave, b-wave, OPs and c-wave were not deteriorated by 1.0 mM FOM. The results of the present study on the human retina were comparable to those on the albino rabbit retina in our previous studies.

Nontoxic concentration of kanamycin and gentamicin for intravitreal use--evaluated by in vitro ERG.

The effects of kanamycin (KM) and gentamicin (GM) on the in-vitro electroretinogram of the albino rabbit were studied. The b-wave and oscillatory potentials (OPs) were unchanged by 0.1 mM KM. The photopic b-wave and OPs were slightly suppressed by 0.4 mM. The b-wave and OPs were not deteriorated by 23 micrograms/ml (approximately 0.05 mM) GM. The photopic b-wave and OPs were slightly suppressed by 46 micrograms/ml (approximately 0.1 mM) GM. The minimum concentration affecting the ERG was tentatively defined as the mean of the minimum concentration needed to change the ERG and the maximum concentration which induced no discernible changes in the ERG. The minimum concentration of KM and GM affecting the ERG were 0.25 mM (approximately 150 micrograms/ml) and 35 micrograms/ml (approximately 0.075 mM) respectively. The minimum concentration of KM affecting the ERG was higher than its minimum inhibitory concentration against Staphylococcus aureus and Streptococcus pneumoniae. The minimum concentration of GM affecting the ERG was higher than its minimum inhibitory concentration against Staphylococcus aureus, Streptococcus pneumoniae and Pseudomonas aeruginosa.

Nontoxic concentration of amphotericin B for intravitreal use--evaluated by in vitro ERG.

Amphotericin B (AMPH)-induced changes of the electroretinogram (ERG) were studied in the in vitro eye-cup of the albino rabbit. The a-wave, b-wave, oscillatory potentials and c-wave were not changed by 1 microM AMPH, and these all were slightly suppressed by 5 microM AMPH. These changes were mostly reversible. The b-wave and oscillatory potentials were greatly suppressed by 50 microM AMPH. These changes were only partially reversible 75 minutes after re-perfusion without AMPH.

Effects of antibiotics on the in vitro ERG of the albino rabbit. Penicillins and cephalosporins antibiotics.

This study describes the effects of penicillin G (PC-G) potassium, PC-G sodium, cloxacillin sodium (MCIPC), disodium sulbenicillin (SBPC), cefazolin sodium (CEZ) and cefsulodin sodium (CFS) on the in-vitro electroretinogram (ERG) of the albino rabbit. The b-wave and oscillatory potentials (OPs) were unchanged by 0.1 mM PC-G potassium or PC-G sodium. The OPs were slightly suppressed by 0.3 mM of either drug. While the a- and b-waves were not deteriorated, the OPs were greatly suppressed by 1.0 mM concentration. The effect of PC-G on the ERG was characterized by a selective suppression of the OPs. The b-wave and OPs were not suppressed by 0.03 mM MCIPC. They were slightly suppressed by 0.05 mM MCIPC. The a-wave, b-wave and OPs were not deteriorated by 1.0 mM SBPC. The b-wave and OPs were suppressed by 3.0 mM or 6.0 mM SBPC respectively. These changes appeared to be dose-dependent. Since the b-wave and OPs were concomitantly suppressed by both MCIPC and SBPC, these antibiotics, unlike PC-G, did not selectively suppress the OPs. The b-wave and OPs were unchanged by 0.1 mM CEZ or CFS. The OPs were slightly suppressed by 0.3 mM CEZ or CFS. CEZ or CFS of 1.0 mM did not deteriorate the a- and b-waves, but selectively suppressed the OPs. The effects of CEZ and CFS on the ERG were characterized by a selective suppression of the OPs. The above-described changes in the ERG were reversible.