[Effects of electromagnetic field with 25, 50 and 100 Hz frequency on serum alanine transaminase and aspartate transaminase activity in mice]

The widespread use of electric power results in exposure of humans to low level 50/60 Hz electric and magnetic fields. There are some controversial reports about the impact of electromagnetic field [EMF] on biological systems. Alanine transaminase [ALT] and aspirate transaminase [AST] are nonspecific enzymes of plasma whose elevations are an indicator of cellular damage. The aim of this investigation was to study the effect of low frequency EMF exposure on activities of serum ALT and AST of mice. In this experimental study twenty four male mice weighting 30 +/- 5 g were divided in four groups each of six animals. The treatment groups were exposed to electromagnetic field [EMF] tensity of 250 microtesla and with frequency of 25, 50 and 100 Hz for one hour per day for thirty days. The control group was in the similar situation without exposure to EMF. The blood samples were taken after thirty days. ALT and AST activities were determined at 37°C by kinetic method. The data were analyzed by SPSS [version 11.5] computer software. Mice serum ALT activity was 84.3 +/- 6.2, 89.8 +/- 14.3 and 84.8 +/- 10.8 IU/L and AST activity was 183.8 +/- 9.1, 185.5 +/- 10.5 and 163 +/- 15.7 IU/L in groups exposed to 25,50 and 100 Hz electromagnetic fields respectively. Significant differences were detected in ALT and AST activities between exposed groups and control group [P<0.05]. In this study, 250 microTesla intensity EMF with 25, 50 and 100 Hz frequency increased the mice serum ALT and AST activities. Serum ALT and AST activities enhancement can be due the electromagnetic fields effect on liver

[Evaluation of binding of FITC-prolactin conjugate to prolactin receptor]

Prolactin is an important mammalian hormone and the associated receptor is recognized in many different cells. Radioligand and histochemical methods are both used for assaying prolactin receptor. To produce FITC-prolactin conjugate and also to study the ability of conjugate to bind prolactin receptor. In this experimental study FITC was bound to prolactin in alkaline solution. FITC-prolactin conjugate was separated from free FITC by chromatographic method. Later, the ability of FITC-prolactin conjugate to bind prolactin receptor of peripheral blood mononuclear cells [PBMC] was assessed by flowcytometry. Fluorescence emission was detected in 2.1% of the cells in absence of FITC-prolactin. Following the addition of FITC-prolactin conjugate to cells for one hour and further washing, the fluorescence emission was detected in 27.8% of cells. For PBMC, these data were 0.02% and 11.8%, respectively. Regarding the data obtained in our study, FITC-prolactin conjugate can bind prolactin receptor. Therefore, this conjugate could be used for assessing prolactin receptor by fluorometric method

[Survey of the status of estrogen and prolactin receptors in breast cancer]

The existence of hormonal receptors in cancer cells is very important in various aspects. Survey of the status of estrogen receptors [ERs] in the evaluation of breast cancer cells is important due to their response to hormonal therapy. Many studies have been recently carried out on prolactin receptors [PRLRs] especially in breast cancer. The aim of the present study was survey of the status of ERs and PRLRs in breast cancer. In this cross-sectional study 40 samples from breast cancer tumors were studied. Estrogen receptor was assessed by radio-ligand binding assay method. Free and total prolactin receptors were also measured using iodinated prolactin [[125]I-PRL]. Magnesium chloride solution [3.5 M] was used to assay the total prolactin receptor. Eighty five percent of tumor samples were ductal tubular carcinoma. In 62.5%, 45% and 62.5% of tumor samples ER, free PRLR and total PRLR were observed respectively. Forty Five percent of the tumor cells expressed both ER and total PRLR. A positive significant relation between ER and free PRLR was observed [p<0.05]. There was also a significant relation [p<0.05] between ER and total PRLR. Twenty Percent of tumor cells expressed neither ER nor total PRLR. Since the existence of estrogen and prolactin receptors in breast tumor cells have been shown, application of antiestrogenic and antiprolactin drugs in the inhibition of these tumors growth are possibly of value

effect of aluminum on human erythrocyte glucose 6-phosphate dehydrogenase

Glucose 6-phosphate dehydrogenase [G6PD], the first enzyme in initiating the pentose phosphate shunt, is an important component in generation of NADPH. Although innumerable studies have been performed on human erythrocyte G6PD, however, the effect of trace elements on the enzyme activity requires further investigations. To study the effect of aluminum on human erythrocyte G6PD. In this experimental research, following the purification of G6PD using chromatographic methods, the effect of different concentrations of Al[3+] [up to 100 micro-molar] on G6PD activity was studied. The enzyme activity was measured at different concentrations of glucose 6-phosphate and NADP[+] to determine the type of inhibitory action. Aluminum at the concentration of 100 microM showed a considerable inhibitory effect on G6PD activity [60%]. The type of inhibitory action, depending on the use of glucose-6-phosphate or NADP[+], was competitive and noncompetitive, respectively. Aluminum exerts an inhibitory action on human erythrocyte G6PD activity