Diabetes mellitus-related morphoquantitative changes in the celiac ganglion neurons of the dog

Diabetes mellitus is the most common endocrine disturbance of domestic carnivores and can cause autonomic neurological disorders, although these are still poorly understood in veterinary medicine. There is little information available on the quantitative adaptation mechanisms of the sympathetic ganglia during diabetes mellitus in domestic mammals. By combining morphometric methods and NADPH-diaphorase staining (as a possible marker for nitric oxide producing neurons), type I diabetes mellitus-related morphoquantitative changes were investigated in the celiac ganglion neurons in dogs. Twelve left celiac ganglia from adult female German shepherd dogs were examined: six ganglia were from non-diabetic and six from diabetic subjects. Consistent hypertrophy of the ganglia was noted in diabetic animals with increase of 55% in length, 53% in width, and 61.5% in thickness. The ordinary microstructure of the ganglia was modified leading to an uneven distribution of the ganglionic units and a more evident distribution of axon fascicles. In contrast to non-diabetic dogs, there was a lack of NADPH-diaphorase perikarial labelling in the celiac ganglion neurons of diabetic animals. The morphometric study showed that both the neuronal and nuclear sizes were significantly larger in diabetic dogs (1.3 and 1.39 times, respectively). The profile density and area fraction of NADPH-diaphorase-reactive celiac ganglion neurons were significantly larger (1.35 and 1.48 times, respectively) in non-diabetic dogs compared to NADPH-diaphorase-non-reactive celiac ganglion neurons in diabetic dogs. Although this study suggests that diabetic neuropathy is associated with neuronal hypertrophy, controversy remains over the possibility of ongoing neuronal loss and the functional interrelationship between them. It is unclear whether neuronal hypertrophy could be a compensation mechanism for a putative neuronal loss during the diabetes mellitus. (C) 2007 Elsevier Ltd. All rights reserved.

Ultrastructural features in the epididymis of the dog (Canis familiaris, L.)

The ultrastructure of the epididymal duct of the dog is described in this paper. The epididymis was divided into three morphofunctional segments: initial, middle and terminal. The cellular population of the lining epithelium is formed from principal, apical, basal and clear cells. The peritubular stroma and the tubular interstitium surrounding the epithelium are also described. The outcome is compared to the description made in other species of mammals.

Some segmental features on the structure of the aortic wall of the dog

Structural features of segmental parts of the aorta of the dog were studied by light microscopy (LM) and scanning electron microscopy (SEM). The variability in the wall architecture composition and vascular thickness of the ascending (T2-3 level), thoracic (T7-8 level) and abdominal (L6-7 infrarenal level) segments of the aorta was analysed. Morphological features such as presence of intimal folds, pattern of the medial myoconnective components with segmental variations in the number of elastic lamellae, whose relative number was higher in the thoracic aorta (ascending and descending parts), compared with the abdominal aorta, and a network of connective (stromal) elements formed by elastic and collagen lamellae and fibres in the adventitia were observed. The results were discussed on a histophysiological basis, because small but significant segmental differences had been characterized in the aortic wall structure of the dog.

Efficacy of the Bm86 antigen against immature instars and adults of the dog tick Rhipicephalus sanguineus (Latreille, 1806) (Acari: Ixodidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Architecture of the caudal vena cava wall of the dog at the level of the liver caudate lobe

The vascular segment of the caudal vena cava of the dog at the level of the caudate lobe was shown to be intimately related to hepatic tissue through the hepatic capsule and parenchyma. The tunica adventitia of the caudal vena cava was formed mainly by smooth muscle cells with collagen and elastic fibers arranged in bundles. The thin tunica media of the vein was also formed by smooth muscle cells, collagen and elastic fibers arranged in bundles. The tunica intima presented an elastic sub-endothelial network. The hepatic segment of the caudal vena cava showed a myoconnective architecture and propulsive characteristics in terms of its hemodynamic pattern.