ANATOMICAL RELATIONSHIPS BETWEEN THE VENTRAL MESENCEPHALIC TEGMENTUM - 10-REGION AND THE LOCUS COERULEUS AS DEMONSTRATED BY ANTEROGRADE AND RETROGRADE TRACING TECHNIQUES

We have searched for anatomical connections between the ventral mesencephalic tegmentum (VMT), including the dopaminergic cell group A10 and the locus coeruleus (LC) region. Tritiated leucine (120-220 nl) and horseradish peroxidase delivered by electrophoresis were injected in the VMT-A10 region. We have demonstrated, on the one hand bilateral projections from the VMT-A10 region to LC, and on the other hand a possible contralateral projection from LC to VMT-A10 region. These relationships, reported for the first time may have some important functional significance. © 1979 Springer-Verlag.