Functional consequences of morphological neuroglial changes in the magnocellular nuclei of the hypothalamus

1. J Neuroendocrinol. 2002 Mar;14(3):241-6.

Functional consequences of morphological neuroglial changes in the magnocellular
nuclei of the hypothalamus.

Oliet SH(1).

Author information:
(1)Inserm U378 and Université Victor Segalen, Bordeaux, France.

Comment in
J Neuroendocrinol. 2002 Mar;14(3):173.

The supraoptic and paraventricular nuclei of the hypothalamus undergo reversible
anatomical changes under conditions of intense neurohypophysial hormone
secretion, such as lactation, parturition and chronic dehydration. This
morphological remodelling includes a reduction in astrocytic coverage of neurones
resulting in an increase in the number and extent of directly juxtaposed somatic
and dendritic surfaces. There is a growing body of evidence indicating that such
anatomical plasticity is of functional significance. Astrocytic-dependent
clearance of electrolytes and neurotransmitters from the extracellular space
appears to be altered under conditions where glial coverage of magnocellular
neurones is reduced. Glutamate, for example, has been found to accumulate in the
extracellular space in the supraoptic nucleus of lactating animals and cause a
modulation of synaptic efficacy. On the other hand, the range of action of
substances released from astrocytes and acting on adjacent magnocellular neurones
is expected to be limited during such anatomical remodelling. It thus appears
that the structural plasticity of the magnocellular nuclei does affect neuroglial
interactions, inducing significant changes in signal transmission and processing.

DOI: 10.1046/j.0007-1331.2001.00766.x
PMID: 11999725 [Indexed for MEDLINE]

Know more about