Induction of hyperadrenergic activity was experimentally achieved in urethane-anesthetized rats using epinephrine (adrenaline). Acute administration of epinephrine (100 microg/kg) for 2 hours induced several cardiac disorders and vasomotor dysfunction. Pretreatment with natural wild honey (5 g/kg) for 1 hour prior to the injection with epinephrine (100 mug/kg) protected the anesthetized normal rats from the incidence of epinephrine-induced cardiac disorders and vasomotor dysfunction. Moreover, posttreatment with natural wild honey (5 g/kg) following the injection with epinephrine (100 microg/kg) for 1 hour showed several ameliorative outcomes to the electrocardiographic parameters and vasomotor dysfunction of anesthetized stressed rats. Furthermore, natural wild honey preserved the positive inotropic effect of epinephrine in both cases. Also, the total antioxidant capacity (AOC) of natural wild honey was found to be very pronounced. Levels of both reduced glutathione and ascorbic acid (vitamin C) were considered relatively high in natural wild honey. Activity of superoxide dismutase (SOD) was also high, whereas catalase activity was relatively low, especially when compared to the value of SOD activity. It would appear from the results of the present study that natural wild honey may exert its cardioprotective and therapeutic effects against epinephrine-induced cardiac disorders and vasomotor dysfunction directly, via its very pronounced total AOC and its great wealth of both enzymatic and nonenzymatic antioxidants involved in cardiovascular defense mechanisms, besides its substantial quantities of mineral elements such as magnesium, sodium, and chlorine, and/or indirectly, via the enhancement of the endothelium-derived relaxing factor nitric oxide release through the influence of ascorbic acid (vitamin C).

The present data on the extracts of C. procera indicate a direct action on the myocardium, stimulatory effect on smooth muscle motility, and relaxant action on skeletal muscle contraction. Chemical constituents could directly affect the cell membrane probably through receptors coupling to G proteins. They regulate the ion channel physiology as in the myocardium.

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Passive sampling could provide the solution to problems associated with costly and time consuming sampling programmes and biomonitoring. Mussels (Mytilus edulis) and Chemcatcher passive sampler were simultaneously analyzed for sequestered pesticides and polychlorinated biphenyls (PCBs) by gas chromatography with mass spectrometry (GC/MSD). The Chemcatcher passive sampler based on a solid phase extraction disc with two types of diffusion-limiting membranes (polyethelene and polysulphone), were also compared. Diuron, atrazine, irgarol and lindane were accumulated in the polysulphone passive sampler in greater concentration than in the mussels or in the other passive samplers with polyethelene limiting-membrane. Mussels can accumulate in their tissue high concentration of non polar compounds such as PCB 52, dieldren and PCB 153; more than the passive sampler with polysulphone membrane. The device with polyethelene limiting membrane has high affinity capacity to concentrate high amount of phenenthrene, dieldrin, PCB 153 and PCB 52, so it acts as a sampler for non-polar compounds. The highest uptake rate of hydrophobic compounds by Chemcatcher was observed for analytes with log octanol-water partition coefficient (K O W ) between 4.5 and 7.5. Laboratorybased studies using passive samplers to assess the potential for bioaccumulation could provide robust and reliable information at relatively low cost compared to biomonitoring data. Laboratory data obtained using passive samplers could be related to accumulation under field conditions where field assessments are required.

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