RESUMEN
PURPOSE: To investigate the in vitro effects of gentamicin sulfate, vancomycin hydrochloride, sodium cefazolin and ceftriaxone on glucose 6-phosphate dehydrogenase enzyme (G6PD) purified from sheep lenses. METHODS: G6PD was purified from sheep lenses with a yield of 66.8% and a specific activity of 7.8 U/mg proteins, and 10,400-fold using ammonium sulfate fractionation and 2',5'-ADP Sepharose 4B affinity gel. The enzyme activity was determined by Beutler's method. RESULTS: Gentamicin sulfate and vancomycin hydrochloride strongly inhibited the enzyme in vitro. The concentrations causing 50% inhibition (IC50 were 15.34, and 8.0 mM, respectively. Conversely, cefazolin sodium strongly activated this enzyme, and ceftriaxone caused milder activation. CONCLUSIONS: If a patient with G6PD deficiency requires gentamicin sulfate or vancomycin hydrochloride, routine ophthalmic did not inhibit this enzyme. Postmortem studies are now needed to investigate the activity of G6PD and how it is affected by these antibiotics.
Asunto(s)
Cefazolina/farmacología , Ceftriaxona/farmacología , Gentamicinas/farmacología , Glucosafosfato Deshidrogenasa/efectos de los fármacos , Cristalino/enzimología , Vancomicina/farmacología , Animales , Antibacterianos/farmacología , Cromatografía de Afinidad , Electroforesis en Gel de Poliacrilamida , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Glucosafosfato Deshidrogenasa/antagonistas & inhibidores , Glucosafosfato Deshidrogenasa/aislamiento & purificación , Glucosafosfato Deshidrogenasa/metabolismo , Técnicas In Vitro , OvinosRESUMEN
PURPOSE: To investigate the efficacy of L-carnitine in preventing retinal injury followed by ischemia-reperfusion. METHODS: The eyes of 34 guinea pigs were used in this experiment. The guinea pigs were divided into two groups: the first group (n=17) was given L-carnitine intraperitoneally (500 mg/kg) and second group (n=17) received the same dose of saline solution. Under general anesthesia, peritomy was performed. Retro-orbital tissues were ligated for 90 minutes and ischemia was induced, followed by 4 hours of reperfusion. One of the enucleated eye was stained with hematoxylin and eosin (H&E) and retinal thicknesses were evaluated. Thiobarbituric acid reactive substances (TBARS) levels were determined in the retina of the other eye. RESULTS: Mean TBARS levels in retinal tissue were found lower in L-carnitine group (2.77 +/- 0.55 microM) than in the control group (6.57 +/- 1.19 microM), (p<0.01). On the other hand, mean retinal thickness was found to be increased in the control group (47.47 +/- 5.62 microm) when compared to the L-carnitine group (26.52 +/- 4.65 microm), (p<0.01). In correlation analysis, significantly positive relationships were found between retinal TBARS level and retinal thickness both in the control and L-carnitine groups (r=0.981, p<0.01 and r= 0.967, p<0.01 respectively). CONCLUSIONS: L-carnitine is effective in preventing retinal injury followed by ischemia-reperfusion.