A artrite reumatoide afeta o sistema nervoso entérico? / Does the rheumatoid arthritis affect the enteric nervous system?

ABSTRACT BACKGROUND: Few studies regarding arthritic diseases have been performed to verify the presence of the neurodegeneration. Given the increased oxidative stress and extra-articular effects of the rheumatoid arthritis, the gastrointestinal studies should be further investigated aiming a better understanding of the systemic effects the disease on enteric nervous system. OBJECTIVE: To determine whether the rheumatoid arthritis affects the nitrergic density and somatic area of the nNOS- immunoreactive (IR) myenteric neurons, as well as the morphometric areas of CGRP and VIP-IR varicosities of the ileum of arthritic rats. METHODS: Twenty 58-day-old male Holtzmann rats were distributed in two groups: control and arthritic. The arthritic group received a single injection of the Freund's Complete Adjuvant in order to induce arthritis model. The whole-mount preparations of ileum were processed for immunohistochemistry to VIP, CGRP and nNOS. Quantification was used for the nitrergic neurons and morphometric analyses were performed for the three markers. RESULTS: The arthritic disease induced a reduction 6% in ileal area compared to control group. No significant differences were observed in nitrergic density comparing both groups. However, arthritic group yielded a reduction of the nitrergic neuronal somatic area and VIP-IR varicosity areas. However, an increase of varicosity CGRP-IR areas was also observed. CONCLUSION: Despite arthritis resulted in no alterations in the number of nitrergic neurons, the retraction of ileal area and reduction of nitrergic somatic and VIP-IR varicosity areas may suggest a negative impact the disease on the ENS.

RESUMO CONTEXTO: Poucos estudos sobre doenças artríticas têm sido realizados para verificar a presença de neurodegeneração. Diante do aumento do estresse oxidativo e dos efeitos extra-articulares da artrite reumatoide, estudos gastrointestinais devem ser investigados visando uma melhor compreensão dos efeitos sistêmicos da doença no sistema nervoso entérico. OBJETIVO: Determinar se a artrite reumatoide afeta a densidade nitrérgica e a área somática dos neurônios mioentéricos imunorreativos ao nNOS (nNOS-IR), bem como para as áreas morfométricas das varicosidades CGRP-IR e VIP-IR do íleo de ratos artríticos. MÉTODOS: Vinte ratos Holtzmann, com 58 dias de idade, foram distribuídos em dois grupos: controle e artrítico. O grupo artrítico recebeu uma única injeção do adjuvante completo de Freund para induzir o modelo de artrite. Os preparados totais de íleo foram processados para imuno-histoquímica ao VIP, CGRP e nNOS. A quantificação foi utilizada para os neurônios nitrérgicos e as análises morfométricas foram realizadas para os três marcadores. RESULTADOS: A doença artrítica induziu uma redução de 6% na área ileal em relação ao grupo controle. Não foram observadas diferenças significativas na densidade nitrérgica comparando os dois grupos. No entanto, o grupo artrítico produziu uma redução da área somática neuronal nitrérgica e da área das varicosidades do VIP-IR. Entretanto, foi observado um aumento das áreas das viricosidades CGRP-IR. CONCLUSÃO: Apesar da artrite não resultar em alterações no número de neurônios nitrérgicos, a retração da área ileal e a redução das áreas somática nitrérgica e das varicosidades do VIP-IR podem sugerir um impacto negativo da doença no sistema nervoso entérico.

Morphology and immunohistochemistry of the myenteric plexus of valves constructed in the colon of rats submitted to abdominoperineal amputation and perineal colostomy

PURPOSE: To investigate immunohistochemical aspects of the myenteric plexus of valves constructed in the colon of rats to verify whether any denervation occurs both at the operative site and in those areas adjacent to the third valve. METHODS: Thirty six male Wistar rats divided into the following three groups were used: Control Group (CG); Amputated Group (AG); Amputated Group with Valves (AGWV). In AG was held in the rectum amputation and the colon was sutured to the skin elaborating the perineal colostomy. In AGWV was held in the rectum amputation. A laparotomy was performed for the manufacture of valves (seromyotomy) in the colon. After this step, the colon was sutured to the skin elaborating the perineal colostomy. The density of the neural elements in the muscular wall as marked specifically using Protein Gene Product (PGP) 9.5 and utilising the proper tools of the KS300 software for measuring the area. From these measurements, a relation and three proportions were drawn and analysed according to the mean of the averages obtained from the measured images. RESULTS: Immunoexpression of PGP 9.5 demonstrated a total absence of neural elements and myenteric plexus at the valve site. The density of the neural elements in the circular muscular layer at sites adjacent to the 3rd valve was lesser, however, was not significantly different. CONCLUSION: The immunohistochemical study of valves constructed in the colon of rats submitted to abdominoperineal amputation and perineal colostomy revealed denervation at the seromyotomy site.

Morphometry and quantification of the myenteric neurons of the cecum of rats (rattus norvegicus) submitted to experimental chronic alcoholism / Morfometría y cuantificación de las neuronas mientéricas del ciego en ratones (rattus norvegicus) sometidos a alcoholismo crónico experimental

Morphometric and quantitative analyses were accomplished to study the effects of the consumption of alcohol above the size and density of the myenteric neurons of cecum of rats. Ten rats with 90 days were divided in the groups: control (C), and alcoholic (A). After 120 days of treatment with ethanol the cecum of both groups were collected, submitted it prepared of membranes that after carried out to Giemsa´s technique, permitted to evaluate the neuronal density, in an area of 13.44mm², and measure the cell body area of 300 neurons by group. The alcoholic rats presented an increase in the number of small neurons and a reduction of the big and medium neurons. The neuronal density verified in alcoholic rats was significantly reduced regarding the controls rats, however, that reduction left of be statistically significant when was projected the neuronal density for the total area of cecum, since the macroscopic observation showed that the alcoholic rats presented a cecum dilated. The alcoholism induced a significant reduction in the final body weight of the rats of the GA, provoked enlargement of cecum of the rats causing to a big dispersion neuronal. The enlargement of cecum of the alcoholic rats is probably associated with the functional alterations of the myenteric neurons that have repercussions in the tone of the intestinal smooth muscle.

Los análisis morfométrico y cuantitativo fueron hechos para estudiar los efectos del consumo de alcohol sobre el tamaño y densidad de las neuronas mientéricas del ciego de ratones. Diez ratones de 90 días, fueron divididos en los grupos: control (C), y alcohólico (A). Después de 120 días de tratamiento con etanol, los ciegos de ambos grupos fueron colectados, sometidos a preparación de membranas que después de coloreados por el método de Giemsa. Fue posible evaluar la densidad neuronal en un área de 13,44 mm2, y medir el área del cuerpo celular de 300 neuronas por grupo. Los ratones alcohólicos presentaron un incremento en el número de neuronas pequeñas y una disminución de las neuronas medianas y grandes. La densidad neuronal verificada en los ratones alcohólicos fue significativamente reducida, en relación a los ratones controles. Esa reducción dejó de ser estadísticamente significativa cuando fue proyectada la densidad de las neuronas para el área del ciego, ya que la observación macroscópica mostraba que los ratones alcohólicos presentaban un ciego dilatado. El alcoholismo indujo una reducción significativa en el peso corporal final de los ratones del grupo A, provocó dilatación del ciego de los ratones, llevando a una gran dispersión neuronal. La dilatación del ciego de los ratones alcohólicos está probablemente asociada a alteraciones funcionales de las neuronas mientéricas que repercuten en el tono de la musculatura lisa intestinal.

Immunohistochemical localization of calcium binding proteins and some neurotransmitters in myenteric plexus of goat stomach

To understand the neurochemical properties of the gastric myenteric plexus of ruminants, the expression patterns of calbindin D-28k (CB), calretinin (CR), substance P (SP) and calcitonin gene-related peptide (CGRP) were explored in the Korean native goat. In gastric myenteric plexus, CB and SP immunoreactivity were observed in round- or ovalshaped neurons. CR and CGRP immunoreactivity were detected only in the nerve fibers. This immunohistochemical localization of CB, CR, CGRP and SP in the myenteric plexus of the goat stomach exhibited species-specific patterns. These findings suggest that these substances may be directly or indirectly related to the gastric functions of the goat stomach.

Effects of protein and vitamin B deficiency on blood parameters and myenteric neurons of the colon of rats

The aims of this work were to evaluate the effects of the deficient ingestion of protein and vitamin B on the biochemical and hematologic parameters and on the NADH- and NADPH-diaphorase positive myenteric neurons. The control animals (n=10) received commercial chow and the experimental rats (n=10) received chow with protein level reduced to 8 percent during 120 days. At the time of killing blood was collected for assessment of the blood and hematologic parameters and the ascending colon for quantitative analysis of the neurons of the myenteric plexus. It was observed that the reduction of the protein level to 8 percent coupled to the reduction of the levels of vitamin B in adult rats neither led to qualitative or quantitative changes on red or white blood cells, nor decreased globulin levels, induced the formation of edema or gave rise to clinical signs typical of protein or vitamin B deficiency. On the other hand, the experimental protocol led to less weight gain, change on the body composition with fat deposition; decrease of the values of serum total protein and albumin; reduction of the area of colon and density of nitrergic and NADH-diaphorase myenteric neurons inferior to the expected