Summary:
This review is a summary of recent neuromorphological observations on the existence
of multisynaptic neural pathways between the endocrine glands and the central nervous
system (CNS) and its structures involved in this pathway. Introduction of the viral
transneuronal tracing technique has made possible investigations of multisynaptic
connections. The utility of this approach is based on the ability of the neurotropic
virus to invade and replicate in neurons, and then gradually infect synaptically linked
second-order, third-order, etc. neurons. Injecting the virus into the endocrine glands,
this technique was used to identify cell groups in the spinal cord and in the brain
which are connected with the adrenal gland, the gonads and the pancreas. Injection
of the virus into these organs resulted in viral labeling of neurons in practically
identical structures of the CNS including the intermediolateral cell column of the
spinal cord, the vagal nuclei and certain other cell groups in the brain stem. In
the hypothalamus the most intensive labeling was in the parvocellular part of the
paraventricular nucleus and in the telencephalon labeled nerve cells were detected
in the amygdala, the bed nucleus of the stria terminalis and in the preoptic area.
It is known that the labeled CNS structures are members of descending pathways arising
from the hypothalamic paraventricular nucleus or from other cell groups and terminating
on neurons of the vagal nuclei and the intermediolateral cell column of the spinal
cord. Experimental data support the view that the CNS structures and pathways connected
with the endocrine glands are involved in the neural control of these organs.
Key words:
Neuronal connections - viral labeling - endocrine glands - neural control - CNS structures
References
β -galactosidase expressing recombinant pseudorabies virus for light and electron microscopic
study of transneuronally labeled neurons.
Brain Res.
555
346-352
1991;
halasz@ana2.sote.hu
