Effect of diethylcarbamazine on acetylcholine and gamma amino butyric acid in Setaria digitata.

In vitro studies on the effect of neurotransmitter amino acids and amines on the motility of S. digitata showed that acetylcholine (Ach) had a stimulatory and gama amino butyric acid (GABA) an inhibitory effect on the parasite. When the worms were incubated in different concentrations of diethylcarbamazine there was a significant dose related increase in the level of Ach, and the level of GABA remained unchanged. Inhibition of acetylcholine esterase activity by diethylcarbamazine caused the accumulation of Ach in the synapses resulting in receptor desensitization and after a momentary stimulation causes paralysis of the parasite.

Changes in the level of biogenic amines in experimentally infected and DEC treated proxy host mice.

The levels of biogenic amines, viz., epinephrine, histamine and dopamine were significantly altered in the blood and brain of the proxy host mice which were infected with the mf of Setaria digitata, a filarial parasite. When DEC, the drug of choice was administered to the infected mice, serotonine level was enhanced while the histamine level was decreased. The results were similar in normal mice which were given DEC.

Effect of diethyl carbamazine on neurotransmitter amino acids, biogenic amines and certain related enzymes in Setaria digitata.

Effect of diethyl carbamazine (DEC) on the levels of neurotransmitter amino acids and on the activities of related enzymes of S. digitata have been studied. When the worms were incubated in DEC, substances known to have neurotransmitter effect were found increased except glycine. Among the amines the level of serotonin, dihydroxy phenyl alanine and epinephrine were increased and that of histamine remained the same. DEC inhibited activities of monoamine oxidase, aspartate amino transferase and alanine amino transferase and enhanced those of cathepsin and glutamate dehydrogenase. The effect of DEC on the activities of the enzymes appear to account for the increased level of amino acids and amines. Results indicate that the reversible paralysis caused by DEC is due to the accumulation of neurostimulants and associated decrease in the concentration of inhibitors.