Resumen de Computational study of the effect of forced exercise (swim stress) on the NADPH-diaphorase activity in the supraoptic nucleus.
María José Polo Martín, Ricardo Vázquez, Fernando Sánchez Hernández, María Navelonga Moreno García 
, M. José López Pérez, Miguel Santos del Rey
Nitricoxide synthesizing neurons of the hypothalamus show changes following a variety of experimental and pathological conditions, such as salt loading, hypotension, cholestasis, water deprivation, and several types of stress including immobilization, exposure to low t e m p e r a t u re and changes of enviro n m e n t . Recently, our group has shown that forc e d e x e rcise (swim stress) is an additional stre s s o r for the nitre rgic neurons located in the paraventricular nucleus of the hypothalamus. On the other hand it is currently well-known, by means of histochemical (NADPH-diaphorase), immunohistochemical and hybridization methods, that the supraoptic nucleus contains an important nitre rgic population of neurons. In the present study, the effect of forced exerc i s e on these neurons was investigated in a computational study of the NADPH-diaphorase positive population of the supraoptic nucleus. A significant increase in the number of positive n e u rons was observed following forced swimming, especially after 30 and 40 min. These data indicate: 1.- The influence of stress on the NADPH-diaphorase-activity in the supraoptic nucleus. 2.- The involvement of hypothalamic nitric oxide synthesizing-neurons in the response to diff e rent types of acute stre s s o r s . 3.- The excellence of a combination of morphological and computational tecniques for the detection of changes in plasticity of the hypothalamic neuro n s .
