Eur J Anat, 2 (1): 35-43 (1998)
NADPH-diaphorase activity in the paraventricular nucleus of the hypothalamus: distribution, coexiztence and functional implications
F.Sánchez1,J.R. Alonso2, R. Arévalo2, J. Carretero1, J. Aijón2 and R. Vázzquez1
1.- Department of Human Anatomy and Histology
2.- Department of Cell Biology and Pathology. University of Salamanca. Faculty of Medicine. Campus Unamuno.
37007 Salamanca. Spain
ABSTRACT In mammals neurons of the hypothalamíc para ventricular nucleus exhibir intense and selecrive sraining (mainly magnocellular component) for NAOPH-diaphorase. Several coexistcnces of this enzyme with neurobiological substances and func tional implications have been reponed. Additio nally, different experimental conditions such as salt loading, food deprívatíon, stress, lactation, hypophysectomy and hormonal treatments promo te changes in the expression of rhe enzyrne in the paraventricular nucleus. In the present paper xve analyze the inforrnation available about the distri bution of NADPH-diaphorase activity in the para ventricular nucleus, the coexistence with different bioactive molecules and its possible functional roles. \Xfe condude that 1.- There is a wiclespread expression of TADPH-cliaphorase activiry in the thrce different rypes of neurons located in rhe paraventricular nucleus (magno-, parvo- anclmediocellular (mes). However, the highest concenp'alion of the neurons showing this activiry is situared at the level of the magnocellular component.2.- These NADPI-l-diaphorase neurons co-express neuropeptides and other neuroactive substances, although there is not él general correspondence with a specific onc suggesting that AOPH-cliap horase is not relared to general mechanisms invol ving rhese subsiances. 3.- NADPH-diaphorase acti vity in rhe paraventricular nucleus can be modulatcd hy differenr hormones and experimental conditions. 4.- Basccl upon rhe foregoíng, nitricoxide proclucing neurons in the paraventricular nucleus are an irnportant cellular population of rhis nucleus involved in multiple mechanisms, espe cially neuroendoerine funcrions. However, the exacr role of rhis messcnger molecule in rhe para ventricular nuclcus is not torally known.
Keywords: Nitric oxide synthase - Coexisience -
Magnocellular - Parvocellular - Mecliocellular.
European Journal of anatomy
ISSN 2340-311X (Online)