[Effect of potassium benzoate on BALB/c mice placenta: a histopathological study]

The food additives, like sodium and potassium benzoate are used in many food products and drugs to prevent the growth of yeast and molds. There is no report about the histopathological effect of potassium benzoate. Placenta, has a critical role in embryonic development therefore this study was set up to evaluate the effects of potassium benzoate on placenta of BALB/c mice. 45 BALB/c female mice were allocated into two experimental [1, 2] and one control groups. Experimental groups received daily intraperitoneal injection of 280 and 560 mg/kg/body weight of potassium benzoate and control group received normal saline. All injections were done during 10 days before mating and 5th to 16th of gestational days [GD]. In GD 18 all placenta were removed via cesarean section. Macroscopic studies for morphological abnormalities were done and after measuring of placental weight and diameter, for microscopic studies the specimens were fixed and tissue passage were done. Tissue sections were stained with hematoxylin-eosin and histopathological changes were studied. Weight, diameter and percentage of agenesis of placenta in all groups were gathered. Data analyzed with using SPSS-11.5, ANOVA and Tukey tests. The mean weight and diameter of the placenta in both experimental groups 1 and 2 were significantly decreased compared to control group. Also atrophy of placenta in the experimental groups was increased significantly compared to the control group [P<0.05]. Comparison of weight and diameter between groups 1 and 2 was not significant. Percentage of placenta agenesis in the experimental groups was increased significantly compared to the control group [P<0.05]. Massive hemorrhage in labyrinth zone, fetal and maternal zones were seen in both experimental groups. This study showed that exposure of potassium benzoate during mice pregnancy cause morphological and histopathological changes of placenta, including decrease of weight and diameter, agenesis, hemorrhage and tissue disorders

Effect of extremely low frequency electromagnetic fields on dtrychnine-induced-convulsions in mice

Effects of electeromagnetic exposure on different parts of neruous system and memory of humans and animals has been established. In spite of important human studies, animal studies have been more precise and comprehensive. Extremely low frequency electromagnetic fields [ELF, <300Hz], have been reported to induce a variaty of behavioral and physiological function changes in animals. The object of present study was to determine the delay and durartion time of convulsions induced by co- exposure of ELF and strychnine. The effects of ELF on convulsions induced by strychnine [1mg/Kg] were investigated in 60 albino mice. Animals were devided into 6 groups [n=10], including control [I], 100Hz and 20Volt [II], 25Hz and 20Volt [III], 25Hz and 260Volt [IV], 100Hz and 260Volt [V], and 100Hz and 260Volt [VI]. Delay time [Det] and duration time [Dut] of convulsions were measured respectively. Increase and decrease in Det and Dut were determined and were compared in control and five ELF exposed groups. There was no significant difference in Det and Dut parameters between control [I] and III, IV and VI groups. In all these groups the convulsions terminated in animal death after a low Dut. In contrast there was a significant difference [P<0.001] in Det parameters between control [I] and the other groups [II and V]. No deaths happened in groups [II and V]. Co-exposure of higher ELF frequency and strychnine may decrease the epileptic effects of the drug