protective effect of Zn-metallothionein [Zn-Mt] on the toxicity of diazinon, mancozeb and their mixture on rats

The joint action of pesticides that have similar chemical structures and mode of toxic action can be predicted. However, this approach and other modeling techniques often provide little insight into the observed toxicity produced by mixtures of pesticides from different classes. The present study shows significant decrease in body weight gain after all exposure periods to diazinon and its mixture with mancozeb. In case of Mancozeb, the percentage body weight gain decreased significantly only after 42 days intake in drinking water. The injection of Zn-MT lead to recover of body weight gain especially in the case of the exposure to diazinon and mancozeb, separately. In case of mixture exposure, Zn-MT treatment reduced the effect until 28 days but the decreasing in body weight gain was still significant [p < 0.05] under the long term exposure until the end of the experiment period. Also a decrease in the activity of plasma cholinesterase after 30 days exposure to mancozeb and its mixture with diazinon was observed and was highly significant [p < 0.01] after 90 days of exposure to diazinon, mancozeb and their mixture. Zn-MT played a role to recover the cholinesterase activity completely in diazinon-treated animals and significantly [p < 0.05] in both mancozeb and the mixture. Alkaline phosphatase was significantly inhibited in plasma after 30 and 90 days in all treatments [p < 0.01] and the injection of Zn-MT leads to a decrease in the injury. The same trend was found in the case of the alkaline phosphatase activity in the liver. The kidney's alkaline posphatase was more tolerant against the effect of both diazinon, mancozeb and their mixture

Synthesis and reactions of 4,6-diaryl-2,3,4,5-tetrahydropyridazin-3-ones

The hitherto unknown 4,6 - diaryl - 2,3,4,5,- tetrahydro - pyridazin - 3-ones III a - e were synthesised from the alpha- aryl, beta-aroylpropionic acids II a-e either by their reaction with hydrazine hydrate or by their conversion to alpha, gamma-diaryl- delta beta, gamma - butenolides [XI], and treatment of the latter with hydrazine hydrate, III afforded 3-chloropyridazin derivative [IV] on its reaction with POCl[3], PCl[5]. The 3-chloropyridazine was treated either with sodium azide producing the tetrazolopyridazine derivative [V] or with acylhydrazines to give the triazolopyridazine derivatives [VI] a-c. 3-Acylpyridazines [VII] a and b were obtained on treatment of III with acetyl chloridies. Ill a was converted to its corresponding thione [VIII], also reacted with benzyl- amine giving 3-N-benzyIpyridazine [IX]. Ill a was dehydrogenated to the corresponding dihydropyridazinone [X]