[Quantitative histochemical study of acetylcholinesterase and succinate dehydrogenase activity in the brain of the suslik Citellus parryi].

Distribution of acetylcholinesterase (AChE) and succinate dehydrogenase (SDH) in some of the structures of the forebrain and midbrain of the Arctic long-tail ground squirrel is similar to that in other mammals. Quantitative histochemical investigation (incubation of slices at 7 and 25 degrees C) showed that onset of hibernation is accompanied by opposite changes in AChE content of different brain structures. Similar studies on the SDH activity in 9 regions of the forebrain and midbrain did not reveal any significant differences between hibernating and active animals, except the substantia nigra where the activity was higher during hibernation.