Effects of malathion subchronic exposure on rat skeletal muscle glucose metabolism.

Regarding the widespread use of organophosphorous pesticides (OP) especially malathion in environment and reported cases of muscle disturbances in human and animal, the present work was undertaken to explore effects of malathion subchronic exposure on rat leg skeletal muscle glucose metabolism by measuring key enzymes of glycogenolysis and glycolysis. Malathion was administered through food for 4 weeks at concentrations of 100, 200, and 400ppm to rats. Activities of enzymes including glycogen phosphorylase (GP), hexokinase (HK), and phosphofructokinase-1 (PFK) were measured in skeletal muscle homogenate of exposed rats.

Induction of insulin secretion by a component of Urtica dioica leave extract in perifused Islets of Langerhans and its in vivo effects in normal and streptozotocin diabetic rats.

The blood glucose lowering effect of Urtica dioica (Stinging Nettle) as a medicinal plant has been noted in old writings such as those of Avicenna. Recently, there has also been other investigators that indicated the hypoglycemic effect of Urtica dioica. But so far, the mechanism of this effect has not been deduced.

DNA as an enzyme. The effect of imidazole derivatives as cofactors and metal ions as activators or inhibitors.

Objective: A highly sensitive spectrofluorometric method using dichlorofluorescin (LDCF) was employed to study the rate of electron transfer reaction in presence of DNA and some imidazole derivatives.

Results: In our experiments, DNA possessed a unique enzyme like catalytic function in oxidative conversion of nonfluorescent LDCF to fluorescent dichlorofluorescein (DCF). The rate enhancement was associated with the turn over constant: k(p) = 10 s(-1) for DNA and cinnamoyl imidazole as a cofactor.