Three PV-containing neuronal populations were described in the torus semicircularis, whereas in the tegmentum, the PV staining was mainly located in the nucleus tegmentalis rostralis and in the Nucleus nervi oculomotorii. 
In the mesencephalon and rhombencephalon, the distribution of immunoreactive fibers was heterogeneous, being most pronounced in a region between the Nucleus nervi oculomotorii and the nucleus interpeduncularis mesencephali, in the nucleus isthmi, and in the raphe region.
The ipsilateral portion of the Nucleus nervi oculomotorii, which is located in the rostral ventral tegmentum mesencephali, supplies the musculi recti inferior and medialis and the musculus obliquus inferior without a clear somatotopic representation of the motoneurons. The nucleus nervi trochlearis, which rostrally joins the Nucleus nervi oculomotorii with a gap of only about 40 micron between the nuclei, is situated completely contralateral to the musculus obliquus superior supplied by it.
The activities of the transmitter enzymes acetylcholine esterase (AChE), monoamine oxidase (MAO) and gamma-aminobutyrate transaminase (GABA-TR) were investigated in the Nucleus nervi oculomotorii of Salmo irideus (Teleostei) during biomorphosis. The activity of MAO was found surrounding the neurons of the Nucleus nervi oculomotorii with stronger deposits of reaction product at the medial surface that is not occupied by cholinergic terminals. The different ways of chemical transmission between nerve terminals and the neurons of the Nucleus nervi oculomotorii are discussed..
-
[ View All ]
