The development of vascularization in the postnatal rat paraventricular nucleus: a morphometric analysis.

: The morphometric analysis of the capillar surface shows the existence of a large amount of vessels in the rat Paraventricular nucleus during postnatal development with respect to the hypothalamic control region in the Anterior hypothalamic area. Quantitative measurements, revealed differences between the subnuclei, but not between the magno- and parvocellular regions. Magnocellular portions involved in Neurohypophysis regulation, showed from 2 to 2.5 times more vascularization than the control region. However, the Posterior subnucleus that projects to the Spinal Cord showed a similar vascularization to that of the control region.