[Angiodysplasia of the colon and Crohn's disease. A study with vascular resin casts]. / Angiodisplasia de colon y enfermedad de Crohn. Estudio con moldes vasculares de resina.

All the previous studies which have associated arteriovenous malformations of the colon with chronic inflammatory disease have always been performed on a diseased intestine. This study, which uses the intravascular injection of resin, shows morphological evidence that angiodysplasia of the colon and intestinal inflammatory disease can coexist independently. This fact suggests that in cases of severe hemorrhage in a patient with inflammatory disease of the small intestine, it cannot simply be assumed that it originates in the macroscopically abnormal intestine, and that angiographic examination is a wise measure to rule out the possibility of arteriovenous malformations in the "normal" intestine.

Neuronal relationships between the dorsal periaqueductal nucleus and the inferior colliculus (nucleus commissuralis) in the cat. A Golgi study.

Cell types in the dorsal periaqueductal nucleus (PAGd) were studied with the aid of the rapid Golgi method in young cats. The neurons were subdivided into fusiform and stellate types with several varieties of the latter class according to the final destination of their axons. Fusiform neurons send their axons to the neuropil of the Ncom. In turn these neurons receive descending fibres from the nucleus commissuralis (Ncom) which seem to establish axo-dendritic contacts. Also commissural neurons receive contacts from ascending fibres of the PAGd. On the basis of Golgi material it is concluded that particular neuronal types of the PAGd could establish reciprocal connections with neuronal elements of the ventral part of the Ncom. The present study supports the hypothesis that the PAGd could be subdivided into discrete cell groups according to their afferent and efferent projections.

Morphological changes of the adrenal gland following soft-laser irradiation of the pineal gland.

We present the results obtained in the adrenal gland of white rats (average weight 220 g) following irradiation of the pineal gland with laser light. Irradiation was carried out with a 5 mW Politec 750 Helium-Neon laser. Total irradiation time was 5 min, with rest intervals of 1 min for every minute of irradiation. Pineal gland irradiation was done under "open sky", i.e., directly at the gland. The effects of the suprarenal gland were studied 3, 7 and 10 d postirradiation. Morphological signs of an increasing activity have been observed in all layers of the cortex and in the medulla of the gland. The highest increase was found 7 d after irradiation in the fascicular zone and in the medulla, and after 3 d in the glomerular and reticular zone. We suggest that laser light induces an inhibitory effect observed at the suprarenal gland. This effect is similar to that found following pinealectomy, showing once again that the pineal gland exerts control on the suprarenal gland, mediated by luminous stimuli.

The commissural nucleus of the inferior colliculus in the rabbit. A morphological study.

The present study describes the essential neuron and axon typology in the nucleus commissuralis of the rabbit inferior colliculus. Cytoarchitectonically, the nucleus is divided in five cellular zones: 1) subpial; 2) plexiform dendritic, 3) central; 4) ventral and 5) periaqueductal zone this latter surrounding the commissural neuropil. Each zone possess particular neuronal types which were described according to its dendritic pattern. In addition, three axonal systems each oriented in a different plane of the commissure of the inferior colliculus were described. Each system possess particular axonal arborizations. Of particular interest is the arrangement of vertical fibres and dendrites in the central zone where they form dendrite and axonal bundles.

Observations on the axonal and neuronal typology in the commissure of the inferior colliculus of the rabbit.

Different types of neurons and fibres in the Commissura colliculi inferiores (CCI) of the rabbit are described using the Golgi rapid method. Neurons were classified according to soma shape, dendritic arborization and location within the commissure. Four main neuronal types were found i.e., (1) Vertical cells; (2) Multipolar cells; (3) Horizontal cells; (4) Small rounded cells. With exception of the latter, all neuron types could be divided into several cells varieties. Four different types of fibres were observed within the CCI: a) myelinated commissural fibres; b) fibres from the dorsal cortex of the colliculus; c) fibres from the dorsal PAG nucleus; d) intrinsic fibres from the neurons of the CCI. The results of this study demonstrate the non-homogeneous structure of the CCI, which was earlier shown in the cat and rat. Also, a division of some of the commissural neurons into local and projecting neurons, based on their axonal branching pattern is suggested.

The commissural neurons of the inferior colliculus of the rat.

During systematic observation of the cellular subnuclei of the inferior colliculus of adult rats, it was noted that in the zone of the intercollicular commissure, numerous neuronal perikaria appear intermingled between the commissural fibers. The neurons were studied using Golgi and TEM methods and classified according to their dendritic pattern in the isodendritic (15%), allodendritic (19%) and intermediate forms (66%) of neurons. A fourth neuronal group, situated between the commissure and the upper periventricular zone, is also in relation with the commissural fibers. The constancy of these neurons and their frequently axodendritic and axosomatic synapses suggest that they play an important role in the whole function of the commissure which, at present, is not well understood in spite of the number and distinct origin of their afferents.