AGE-RELATED CHANGES OF SUBSTANTIA NIGRA OF THE RAT BRAIN:Ⅱ.QUANTITATIVE ANALYTICAL STUDY ON ACETYLCHOLINESTERASE ACTIVITY BY USING IMAGE ANALYSIS SYSTEM / 解剖学报

By means of pharmacohistochemical regimen method and image analysis system,the age-related changes of acetylcholinesterase activity of the substantia nigra neu-rons and the number and size(section area)of the AChE positive neurons in ratswere investigated quantitatively.The results showed that the number of AChE pos-itive neurons in the substantia nigra of the old rats decreased markedly,the rateand quantity of AChE synthesis in the perikaryon remarkable declined.The size(section area)of the AChE positive neurons also reduced with aging.These changeswith aging have never been studied in human or usual experimental animals,so thatsome new parameters were provided for the research field in experimental geronto-logy.In human and animal,the degeneration of the neurons in substantia nigra cau-sed by aging would disturb the balance between dopaminergic and acetylcholinergicsystem and hence interfere with the normal coordination of movement.

ACETYLCHOLINESTERASE STAINING PATTERNS OF THE TECTUM NUCLEUS ISTHMI SYSTEMS IN FROGS AND PIGEONS / 解剖学报

This paper, using acetylcholinesterase (AChE) histochemistry, brain-lesion and di-isopropylfluorophosphate (DFP) pretreatment techniques, studies AChE distribution in the tectum-nucleus isthmi systems in frogs and pigeons. In these two species of animals, the tectal laminae densely stained for AChE are roughly coincided with the retinotectal projections. Staining pattern in the frog nucleus isthmi consists of 3 areas with different staining intensities. The dorsolateral area being most densely stained. In pigeons, the nucleus isthmi pars parvocellularis (Ipc) and pars magnocellularis (Imc) are densely and evenly stained. Following local lesion of tectum, stainings in the frog nucleus isthmi and pigeon Ipc are topographically reduced or disappeared. DFP-treatment shows that tectal cells, with the exception of cells in layer III containing rich AChE, have moderate or low concentrations of AChE. The isthmic cells are rich in AChE. In the tectum-lesioned pigeons, AChE-stained isthmic cells in the topographical area are reduced in number and paler in color. These results suggest that in amphibians and birds both the tectoisthmic projection and the isthmotectal projection could be cholinergic pathways in nature.