RESUMO
The purpose of this work was to study the area of the varicosities of nerve fibers of myenteric neurons immunoreactive to vasoactive intestinal peptide (VIP-IR) and of the cell bodies of VIP-IR submucosal neurons of the jejunum of diabetic rats supplemented with 2% L-glutamine. Twenty male rats were divided into the following groups: normoglycemic (N), normoglycemic supplemented with L-glutamine (NG), diabetic (D) and diabetic supplemented with L-glutamine (DG). Whole-mounts of the muscle tunica and the submucosal layer were subjected to the immunohistochemical technique for neurotransmitter VIP identification. Morphometric analyses were carried out in 500 VIP-IR cell bodies of submucosal neurons and 2000 VIP-IR varicosities from each group. L-Glutamine supplementation to the normoglycemic animals caused an increase in the areas of the cell bodies (8.49%) and varicosities (21.3%) relative to the controls (P < 0.05). On the other hand, there was a decrease in the areas of the cell bodies (4.55%) and varicosities (28.9%) of group DG compared to those of group D (P < 0.05). It is concluded that L-glutamine supplementation was positive both to normoglycemic and diabetic animals.
Assuntos
Suplementos Nutricionais , Sistema Nervoso Entérico/patologia , Glutamina/administração & dosagem , Jejuno/inervação , Neurônios/patologia , Substâncias Protetoras/administração & dosagem , Peptídeo Intestinal Vasoativo/metabolismo , Aminoácidos Essenciais/administração & dosagem , Animais , Antioxidantes/administração & dosagem , Peso Corporal , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Dieta , Sistema Nervoso Entérico/imunologia , Sistema Nervoso Entérico/metabolismo , Técnica Indireta de Fluorescência para Anticorpo , Hemoglobinas Glicadas , Jejuno/metabolismo , Jejuno/patologia , Masculino , Plexo Mientérico/imunologia , Plexo Mientérico/metabolismo , Plexo Mientérico/patologia , Neurônios/imunologia , Neurônios/metabolismo , Ratos , Ratos Wistar , Plexo Submucoso/imunologia , Plexo Submucoso/metabolismo , Plexo Submucoso/patologiaRESUMO
After acute infestation with the Chagas disease parasite, Trypanosoma cruzi, some patients who are serologically positive develop chronic megacolon and megaesophagus, whereas others are symptom-free. Chagas disease with gastrointestinal involvement involves an inflammatory invasion of the enteric plexuses and degeneration of enteric neurons. It is known that glial cells can be involved in enteric inflammatory responses. The aims were to determine the nature of any difference in lymphocytic invasion, enteric neurons, and enteric glial cells in seropositive individuals with and without megacolon. We have compared colonic tissue from serologically positive individuals with and without symptoms and from seronegative controls. Subjects with megacolon had significantly more CD-57 natural killer cells and TIA-1 cytotoxic lymphocytes within enteric ganglia, but numbers of CD-3 and CD-20 immunoreactive cells were not significantly elevated. The innervation of the muscle was substantially reduced to about 20% in megacolon, but asymptomatic seropositive subjects were not different to seronegative controls. Glial cell loss occurred equally in symptomatic and unaffected seropositive subjects, although the proportion with glial fibrillary acidic protein was greater in seropositive, nonsymptomatic subjects. Development of megacolon after acute infection with T cruzi is associated with maintained invasion of enteric ganglia with cytotoxic T cells and loss of muscle innervation, but changes in glial cell numbers are not associated with progression of enteric neuropathy.