抄録
Histochemical studies have been conducted on the interpeduncular nucleus (IPN) of the rat. The neurons of such show a high level of hexokinase activity and are able to receive their energy supply directly from glucose in the circulating blood. These neurons are equally supplied with the enzymes of the Embden-Meyerhof pathway and with those of the hexose monophosphate shunt, indicating a high level of activity in the tricarboxylic acid cycle. Therefore, the rat IPN may belong to the category of“usual nuclei” (15, 16).
Neurons were classified into five categories based on variousmorpho-logical patterns in the Golgi apparatus (GA). Type I and II neurons were dominant in the Corpus interpedunculare (Ci), and types III, IV and V neurons were dominant in the magnocellular nucleus (Mi) of the IPN. In general, the activities of the glycolytic enzymes such as hexokinase, aldolase, glycero-aldehyde-3-phosphate dehydrogenase, lactate dehydrogenase and succinate dehydrogenase were higher in the Ci than in the Mi. These results indicate that the rat IPN may be classified histochemically into two subnuclei.
The high succinate dehydrogenase activity sporadically localized in the neuropil suggests that it may correspond to the structures formed by the horizontal axonplexus and by the richly ramified dendrites of the neurons in the IPN.
