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Background: Parathion is an organophosphate compound that is frequently used as an insecticide. Paraoxon is the metabolic product of parathion which previously reported that inhibits GABA uptake by rat cerebral cortex synaptosomes. The aim of this study is to investigate possible underlying inhibitory mechanism(s) of paraoxon on GABA uptake, in synaptosomes prepared from rat cerebral cortex. Materials and Methods: After preparation of synaptosomes, kinetic studies were performed to determe the effect of paraoxon on Km and Vmax of GABA uptake. Acetylcholine and its antagonists (atropine and mecamylamine) were used to evaluate cholinergic dependency of GABA uptake. Type of GABA transporter involved was determined using beta-alanine and DABA. Results: The results of the study showed that paraoxon significantly decreased Vmax (175.2±4.23 vs. 80.4±2.03 pmol/mg protein/min, P<0.001) of GABA uptake while had no effect on its km (9.80±1.02 vs. 9.09±0.92μM in paraoxon and control groups respectively). DABA significantly decreased GABA uptake (P<0.001) while beta-alanine had no effect. Acetylcholine had no effect on GABA uptake. On the other hand, neither atropine nor mecamylamine could reverse the inhibitory effect of paraoxon on GABA uptake. Conclusion: In conclusion, it seems that paraoxon acts as non-competitive anatagonist of GABA uptake, which affects kinetics of GABA uptake in nerve endings. We also conclude that the inhibitory effect of paraoxon on GABA uptake is cholinergic-independent

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Background and Aim: The volkmann syndrome is ischimia and muscular necrosis due to pressure augmentation in the closed aponeurotic compartments of the forearm region. The incidence of this syndrome in Iran is more than the normal incidence, since non-medical people perform bandage or casting too tightly, for the treatment of forearm lesions. Materials and Methods: A total of 67 patients, 64 male and three female, ranging in age from 7 to 18 years with the average of 13 years were treated by one of the four methods of Scaglietti, Latissimus dorsi Island flap, Gracilis free muscle transfer or Biceps tendon transfer. Results: From 33 patients with some muscle contracture who underwent flexor muscle advancement (Scaglietti technique) 25 (71.4%) resulted in excellent, and 10 (28.6%) resulted in good outcome. Latissimus dorsi Island flap resulted in 20 (90.9%) excellent, and and 2 (9.1%) good results in total of 22 patients. Gracilis muscle transfer in 4 patients resulted in 4 good outcomes (100%). Six biceps tendon transfer procedure resulted in 6 good outcomes (100%). ‍Conclusion: If some forearm muscle contraction is revealed in the physical examination, good results can be obtained by performing the Scaglietti procedure. We did not have any muscle necrosis of the transferred latisimuss dorsi island flap, or musculocutaneous gracillis free flaps transferred. The transfer of biceps tendon to the digital flexor tendon yields in acceptable results for the patients. But the patient needs good re-education and physiotherapy for adaptation to the new condition.