RESUMEN
Radioprotective effectiveness has been evaluated by 30 day survival studies and protection to bone-marrow cells in mice after radiation exposure and this has been further established by 24 hr deoxycytidine excretion in urine of rats following 5 Gy whole body gamma irradiation and protection to superoxide dismutase enzyme in marrow cells and red blood corpuscles. Radioprotective effectiveness as well as the duration of radioprotection have been improved by the administration (ip) of hydroxylamine (20 mg/kg), a decarboxylase inhibitor, prior to the use of a combination of 5-hydroxy L-tryptophan (5-HTP, 70 mg/kg) and 2-aminoethylisothiuronium bromide hydrobromide (AET, 20 mg/kg) ip in small mammals before whole body gamma irradiation.
Asunto(s)
Hidroxilaminas/administración & dosificación , Protectores contra Radiación/administración & dosificación , 5-Hidroxitriptófano/administración & dosificación , Animales , Médula Ósea/efectos de los fármacos , Médula Ósea/enzimología , Médula Ósea/efectos de la radiación , Hidroxilamina , Masculino , Ratones , Ratas , Ratas Sprague-Dawley , Superóxido Dismutasa/metabolismo , beta-Aminoetil Isotiourea/administración & dosificaciónRESUMEN
Rate of glycolysis in vivo at different time intervals following 8 Gy [LD100(30)] whole body gamma radiation (WBGR) was evaluated by estimating liver glycogen, blood sugar, serum lactic dehydrogenase (LDH) and blood lactic acid concentration in adult male Sprague Dawley rats. Within 1 hr of radiation exposure, a significant fall in liver glycogen was observed in rats fed food and water ad libitum. The glycogen content increased after 24 hr and had returned to control level on 7th day after radiation exposure. Blood sugar, serum LDH and blood lactate levels increased significantly as compared to non irradiated controls. Pretreatment with 5-hydroxy-L-tryptophan (5-HTP; 100 mg/kg) + 2-aminoethylisothiuronium bromide hydrobromide (AET; 20 mg/kg) ip 30 min before 8 Gy WBGR, modified these values and restored them to normal level on 7th day post-irradiation.
Asunto(s)
5-Hidroxitriptófano/administración & dosificación , Glucólisis/efectos de los fármacos , Glucólisis/efectos de la radiación , beta-Aminoetil Isotiourea/administración & dosificación , Animales , Rayos gamma , Glucógeno Hepático/metabolismo , Glucógeno Hepático/efectos de la radiación , Masculino , Protectores contra Radiación/administración & dosificación , Ratas , Ratas Sprague-DawleyRESUMEN
Radioprotective efficiency of the combination of 5-hydroxy-L-tryptophan (5-HTP, 100 mg/kg) with 2-aminoethylisothiuronium bromide hydrobromide (AET, 20 mg/kg) in protecting splenic tissue following 8 Gy whole-body gamma radiation (WBGR) has been studied in adult male Sprague Dawley rats. Loss in splenic weight, splenic cells and DNA was observed following & Gy WBGR, which was modified significantly in 5-HTP+AET (ip) pretreated group. The study further showed that pre-treatment with this formulation led to an increased superoxide dismutase (SOD) activity and a decrease in lactate/pyruvate ratio in the cytosol fraction of the spleen.
Asunto(s)
5-Hidroxitriptófano/administración & dosificación , Traumatismos Experimentales por Radiación/prevención & control , Protectores contra Radiación/administración & dosificación , Bazo/efectos de los fármacos , beta-Aminoetil Isotiourea/administración & dosificación , Animales , ADN/efectos de los fármacos , ADN/efectos de la radiación , Evaluación Preclínica de Medicamentos , Quimioterapia Combinada , Masculino , Traumatismos Experimentales por Radiación/metabolismo , Ratas , Ratas Endogámicas , Bazo/metabolismo , Bazo/efectos de la radiación , Superóxido Dismutasa/efectos de los fármacos , Superóxido Dismutasa/efectos de la radiación , Factores de TiempoRESUMEN
Differential radioprotection between normal tissues and carcinoma was observed in C3H/J mice treated with a combination of 5-hydroxy L-tryptophan (5-HTP, 100 mg/kg) and 2-aminoethylisothiuronium bromide hydrobromide (AET, 20 mg/kg). Protection to normal tissues was judged by LD50(30) and by radiation induced damage to bone marrow(BM) using clonogenic ability of blood forming stem cells (10 day CFUs) as the criteria. Pretreatment with 5-HTP + AET combination 30 min before whole body gamma radiation (WBGR) enhanced the recoveries of the number of blood forming stem cells in BM of irradiated mice after 0, 7th and 10th day of irradiation. LD50(30) for C3H/J mice was 7.3 Gy and the dose modifying factor (DMF) of 5-HTP + AET combination was 1.76. On the contrary, pretreatment with this combination did not protect the mammary carcinoma transplanted in C3H/J mice, when exposed to 80 Gy soft X-rays.
Asunto(s)
5-Hidroxitriptófano/farmacología , Médula Ósea/efectos de la radiación , Protectores contra Radiación/farmacología , beta-Aminoetil Isotiourea/farmacología , Animales , Médula Ósea/efectos de los fármacos , Células de la Médula Ósea , Supervivencia Celular , Combinación de Medicamentos , Femenino , Rayos gamma , Masculino , Neoplasias Mamarias Experimentales , Ratones , Ratones Endogámicos C3H , Células Madre Neoplásicas/citología , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/efectos de la radiaciónRESUMEN
Radiation induced changes in testicular activity were studied by estimating sialic acid content in plasma and testis and 17-ketosteroids in 24 hr urine samples of male Sprague Dawley rats following 8 Gy whole body gamma ray exposure with and without pretreatment with 2-aminoethylisothiuronium bromide hydrobromide (AET) or with a combination of 5-hydroxy L-tryptophan (5-HTP) and AET. Combination of 5-HTP with AET or AET alone in optimum radioprotecting dose has significantly modified the radiation damage to the testis.
Asunto(s)
5-Hidroxitriptófano/farmacología , Compuestos de Sulfhidrilo/farmacología , Testículo/metabolismo , Animales , Masculino , Ratas , Ratas Endogámicas , Testículo/patología , Testículo/efectos de la radiación , Irradiación Corporal TotalRESUMEN
Sodium homeostasis in adult male albino Sprague Dawley rats has been examined 24 hours after exposure to 11 Gy whole-body gamma irradiation. Rate of influx of 22Na in red blood corpuscles (in vitro) of irradiated rats significantly increased and was modified by the administration of some radioprotective drugs prior to irradiation. Solcoseryl and AET (200 mg/kg) gave excellent protection and the combinations of 5-HTP with AET or MPG rendered better protection than when used alone.