European Journal of Anatomy

Official Journal of The Spanish Society of Anatomy
Cover Volume 2 - Number 2
Eur J Anat, 2 (2): 115-122 (1998)

Subdivisions of the human substantia nigra using AChE histochemistry

A. Carmona, R. Jiménez-Castellanos, C.J. Catalina-Herrera, J. Ambrosiani and J. Jiménez-Catellanos

Departamento de Ciencias Morfológicas. Universidad de Sevilla, 41009 Sevilla. Spain

ABSTRACT The present work describes the neurochernical activity detected in the nigral complex of the adult human using the acetylcholinesterase histo­ chemical technique. Such activity is seen at cell level in the pigmented neurons of the pars com­ pacta of the substantia nigra, and, to a lesser degree, in the paranigral neuronal groups (ven­ tral tegmental area and retrorubral field). There is also considerable enzymatic activity in the neu­ ropil of the substantia nigra. However, the pars lateralis and overall the ventromedial portion of the substantia nigra present a relativeJy low acetylcholinesterase content, though both have so me acetylcholinesterasic neuronal bodies. A series of studies in different species suggested that in the substantia nigra, AChE is released almost exdusively from dopaminergic nígrostria­ tal neurons and precisely from their dendrites, which protrude widely into de pars reticulata. In addition, previous findings made in the cat and in the monkey reported a direct correlation bet­ ween nigral AChE activity and nigrostriatal con­ nections. The non-uniform distribution of AChE activity within the human nigral complex repor­ ted here may indicate the modular organization of the intrinsic neurons of the substantia nigra and their mesostriatal projections.

Keywords: Acetylcholinesterase - substantia nigra - human - hístochernístry - basal ganglia

European Journal of anatomy
ISSN 2340-311X (Online)