The aim of the present study was to evaluate the radioprotective effect of diltiazem (DTZ) on Swiss albino mice exposed to gamma radiation. In the present study, radioprotective efficacy of DTZ (a calcium channel blocker) was studied against radiation induced haematological and biochemical alterations. Swiss albino mice of 6-8 weeks old were administered diltiazem (100 mg kg(-1) by weight) intraperitoneally prior to whole body gamma-irradiation (7.5 Gy). Radiation exposure resulted in a significant decline in different bone marrow cells (pro- and normoblasts) and blood constituents (erythrocytes, leukocytes, differential leukocyte count, haematocrit, haemoglobin and erythrocyte sedimentation rate). Pro- and normoblasts, erythrocytes, leukocytes, haematocrit and haemoglobin values showed a significant (p<0.0051) decline until day 3, following a gradual recovery from day 7, but normal values were not recorded until 28 days post-exposure. In contrast, erythropoietin levels increased significantly and reached a maximum on day 3. In DTZ pre-treated irradiated animals, a significant increase in pro- and normoblasts, erythrocytes, leukocytes, differential leukocyte count, haematocrit and haemoglobin values, and a significant decrease in erythropoietin values, were observed compared with control. A significant elevation above normal in lipid peroxidation level was recorded in gamma irradiated mice, whereas this increase was considerably less in DTZ pre-treated animals. Similarly, pre-treatment of DTZ caused a significant increase in erythropoietin and glutathione levels in serum in comparison with irradiated animals. From our study it is clear that DTZ provides protection against radiation-induced haematological and biochemical alterations in Swiss albino mice.

No abstract

The chemopreventive potential of rosemary (Rosmarinus officinalis) on 7,12-dimethlybenz(a)anthracene (DMBA) initiated and croton oil promoted mouse skin tumorigenesis was assessed. The modulatory effects of R. officinalis was monitored on the basis of the average latency period, tumor incidence, tumor burden, tumor yield, tumor weight and diameter as well as lipid peroxidation and glutathione level. The results indicate that R. officinalis leaves extract could prolong the latency period of tumor occurrence, decrease the tumor incidence, tumor burden and tumor yield. The average weight and diameter of tumors recorded were comparatively lower in the rosemary extract treated mouse groups. The level of lipid peroxidation was significantly reduced in blood serum and liver. Furthermore, depleted levels of glutathione were restored in RE-administered animal groups. Thus, at a dose rate of 500 mg/kg body wt/mouse, the oral administration of rosemary extract was found to be significantly protective against two-stage skin tumorigenesis.

The radioprotective effect of Rosemarinus officinalis extract (ROE) was studied in mice exposed to 8 Gy of gamma radiation. The optimum dose for radioprotection was determined by administering 100, 200, 400, 800, 1000, 1500, and 2000 mg/kg body weight of ROE orally once daily, consecutively for five days before irradiation. Treatment of mice with ROE, delayed the onset of mortality and reduced the symptoms of radiation sickness when compared with the non-drug-treated irradiated controls. The dose of ROE found to be most effective against radiation was 1000 mg/kg body weight because this dose increased the survival time and reduced the mortality rate of mice significantly. Body weight loss in ROE administered irradiated animals was significantly less in comparison with animals who were given radiation treatment alone. Furthermore, irradiation of animals resulted in an elevation in lipid peroxidation (LPx) and a significant decrease in glutathione (GSH) in blood and liver. Conversely, administration of animals with ROE before irradiation caused a significant decline in LPx accompanied by a significant increase in GSH concentration. The present study demonstrates that Rosemarinus officinalis leave extract is a good radioprotector.