Morphometric and neurosecretory changes in supraoptic neurons after D-amphetamine treatment.

Several morphological and immunochemical characteristics of the neurosecretory neurons of the supraoptic nucleus (SON) have been studied of rats treated for 1 month with D-amphetamine sulfate (AMP) (8 mg/kg weight, daily). An increase of SON volume (11%) has been observed as a consequence of the growth of the dorsoventral axis. Neurosecretory neurons increased their nucleolar area (11.4%), their nuclear area (8.3%), and their cytoplasmatic area (18.3%). Vasopressin immunoreaction did not show any differences between treated and control animals, but oxytocin immunostaining displayed an important increase (23.7%) in the neuronal cytoplasm of the treated rats. The SON hypertrophy of the AMP-treated rats corresponded to the hypertrophy/hyperfunction of its oxytocinergic neurons, and could be considered as a new mechanism of the action of the AMP. The results are discussed in relation to the plastic features of the SON and its central (neuronal) and peripheral (hormonal) function.

Morphometric study on the development of magnocellular neurons of the supraoptic nucleus utilising immunohistochemical methods.

Vasopressin (VP)- and oxytocin (OXY)-producing neurons, components of the rat supraoptic nucleus, have been located with immunohistochemical methods, with the purpose of studying their morphofunctional characteristics during different phases of life (embryonic, juvenile, adult and senile). To carry out this study, an IBAS I (Kontron) computerised image analyser has been utilised. The hormone VP is first detected in the neuronal cytoplasm of 21 days old rat embryos and the hormone OXY appears in the neuronal cytoplasm later, in the newborn phase. The neuronal area with a positive reaction for the two neurohormones has been evaluated and it has been found that the quantity of reaction substance is proportional to the age. In the adult period, VP neurons possess a reaction area (198 microns 2) greater than that of OXY neurons (153 microns 2). In the SON, there are two neuronal shapes, fusiform and round; these shapes coexist in both hormonal types of neurons. Until Day 15 of postnatal development, the SON neurons are intermixed in the interior of the nucleus but in this period a neuronal redistribution is initiated. In the adult phase, OXY neurons are situated preferentially in the anterior, posterior and dorsal parts and VP neurons in the ventral and posterior parts, with both neurons being present in the intermediate part of the SON.

Morphometric changes between one-day-old and adult chicken neurons of the nucleus isthmi.

The most important parameters of the neuronal soma of neurons of the chicken nucleus isthmi have been analyzed, with photo and morphometric techniques, in order to quantify the morphological variations present during the first months of the life to determine if the developmental changes of both neuronal populations of the nucleus are similar or different. The study was carried out on neurons of the parvicellular part and magnocellular part of the Nucleus Isthmi in one day and four month-old chickens. The soma shape did not change during this time interval in parvicellular neurons. The magnocellular neurons became more fusiform. In-one-day old chickens, the section shapes of the neuronal soma and optical density, are similar in both the magnocellular and parvicellular parts of the nucleus. The area and the maximum and minimum diameters do not present significant differences between magnocellular and parvicellular neurons. In adults, the maximum diameter, neuronal area and optical density are higher in magnocellular neurons than in parvicellular neurons. In summary, magnocellular neurons of the nucleus Isthmi of adults are bigger, darker and more elongated than the ones that constitute the parvicellular territory.

Topographical development of the supraoptic nucleus of the rat.

Topographical changes in the development of the principal part of the supraoptic nucleus (SON) of the rat were studied by analyzing its tridimensional images, from the intrauterine to the senescent stage. Evaluation of the growth rate of the SON was also made possible by this procedure. From the onset of the appearance of the SON, changes in its spatial orientation were marked by a progressive increase in the antero-posterior and medio-lateral dimensions. The ventro-dorsal one increased up to 6 months of age and then began to decrease progressively. These changes were accompanied by a ventral displacement that became indistinct at 6 months, whereas the lateral migration persisted. No rostro-caudal displacement was recognized. Possible reasons for these changes are briefly discussed.

Development of the chicken oculomotor nucleus: a quantitative study of cresyl violet and colloidal iron stained neurons.

The characteristics of new-born chicken oculomotor neurons have been studied comparatively with adults (four-months), applying both, the Cresyl Violet and Colloidal Iron stain methods. A cytophotometric study has been performed on the neurons, obtaining optical density maps. Afterwards, a statistical study on the nuclear and somatic parameters, and the optical density values, were made. The existence of two nerve-cell types has been proved: clear ones-big, eggshape with nucleus and an obvious nucleolus; and darker ones-smaller, fusiforms, with nucleus and a less perceptible nucleolus. These characteristics of the neuronal-cells are present in new-born and four-month old animals. The ratio is different for each stage: in younger chickens there is a bigger proportion of clear nerve-cells (70%) than dark ones (30%); and in four-month old chickens there is a bigger proportion of dark nerve-cells (95%) than clear ones (5%). During postnatal development, oculomotor nucleus nerve-cells increased the neuronal area 28% in the clear cells and 30% in the dark cells. The optical density histograms for clear cells of one-day old animals and four-month old animals were similar, as were the histograms for both developmental stages of the dark cells. Glycosaminoglycans were shown with the colloidal Iron, there being strong positive reactions on the cell periphery, prolongations, and Golgi apparatus of four-month old specimens. But in the nex-born animals the reaction was weaker, with the maximum intensity on the pericaryon periphery.

Dipiridamol/acido acetilsalicilico en la prevencion de tromboembolismo en artroplastia total de cadera. / Dipyridamole/acetylsalicylic acid in the prevention of thromboembolism in total hip arthroplasty.

A 525 pacientes sometidos a artroplastia total de cadera, tipo Charnley, se les administro dipiridamol y acido acetilsalicilico como tratamiento profilactico de la tromboembolia. Se suspendio el tratamiento a 91% de estos pacientes en vista de presentar gastritis por la administracion de acido acetilsalicilico y a 12% por presentar cefalea consecutiva a causa del dipiridamol. Se observo trombosis venosa profinda en 7.97% de los pacientes; 5.07% presento embolia pulmonar con 0.24% de mortalidad.