We carried out this study with the purpose of contributing on the effects of the proteic desnutrition on the morphological aspects and quantitative analysis of the neurons in the myenteric plexus of the ascending colon of adult Rattus norvegicus. Twenty adult rats were divided into two groups: in one of them, we offered a normal ration with proteic level of 22% (control group) and in the other, a ration with a proteic level of 8% (experiment group) during 120 days. We did the whole-mount preparations for the ascending colon and stained them with the Giemsa technique and the histochemical technique of NADH-diaphorase. The rats with proteic desnutrition showed a body weight, on average, to be 35.1% less than those of the control group, and the colon was on average, 26.8% shorter and 6.7% narrower. Thus, it was to be expected that the colon of animals with proteic desnutrition had a neuronal density 31.62% greater than the rats of the control group. Nevertheless, the difference with the Giemsa technique was on average 18.4%, demonstrating a mean neuronal loss of 13.25%.

The purpose of this work was to study the neurons of the myenteric plexus of the cecum of rats with chronic streptozotocin-induced diabetes. We used four experimental groups of animals. In groups D2 and D8 animals were killed two and eight months, respectively, after diabetes induction and groups C2 and C8 were used as controls. We carried out whole-mount preparations stained with Giemsa and NADH-diaphorase. We verified that the diabetes did not alter the shape and disposition of the myenteric ganglia; it provoked decrease on the neuronal density and increase on the incidence of weakly basophilic neurons. The effects of streptozotocin caused dilatation of the cecum still evidenced two months after induction, but no more observed on the eight months after induction. The smaller incidence of neurons in group D8 relative to group C8 was due to the early loss related to the drug toxicity and later to the aging in diabetic condition.

-The purpose of the present study was to investigate the morphological and quantitative alterations of the myenteric plexus neurons of the stomach of rats with streptozotocin-induced chronic diabetes and compare them to those of non-diabetic animals. Samples from the body of the stomach were used for wholemount preparations stained with NADH-diaphorase and for histological sections stained with hematoxylineosin. It was observed that diabetes cause a significant decrease on the number of neurons.KEY WORDS: myenteric plexus, diabetes, rat.Estudo quantitativo do plexo mientérico do estômago de ratos com diabetes induzido por estreptozootocina RESUMO -A proposta deste trabalho foi estudar as alterações morfológicas e quantitativas dos neurônios do plexo mientérico do estômago de ratos com diabetes induzido por estreptozootocina e estabelecer uma comparação com animais não diabéticos. Amostras do corpo do estômago foram submetidas a preparados de membrana corados pelo método da NADH-diaforase e a cortes histológicos corados por hematoxilinaeosina. Observou-se que o diabetes provoca significante redução no número de neurônios. Diabetes mellitus is a pathological condition in which several physiological abnormalities are observed, such as neuropathies that affect the central nervous system, the peripheral nerves and the autonomic nervous system 1 . Streptozotocin-induced diabetes causes a cycle of events in the nerve cells of the myenteric plexus that begins within one to three days, with the development of chromatolysis followed by regenerative changes over the next six weeks, with some continuous, albeit occasional, ganglionic degeneration 2 ; changes in the innervation of the ileum and colon 3 are reported, as well as a decrease on the neuronal activity 4 . Studies on streptozotocininduced diabetic rats have emphasized the alterations that occur in the small and large intestines. However, it should be remembered that alterations in the neurons of the myenteric plexus, in addition to changing intestinal peristalsis, can affect stomach motility, leading to dilation and retarded gastric emptying, interfering with the coordination between stomach and duodenum and impairing the digestive process 5 . PALAVRAS-CHAVEIn a diabetic ketonuric Chinese hamsters examination of the gastrointestinal tract was observed that the animals had distention and atony of the stomach and intestines when compared with control animals 6 . In humans, among the clinical manifestations of autonomic neuropathy, there is motor impairment of the stomach, which can lead to anorexia, nausea, vomiting and persisting fullness, characterizing gastric debilitation 1,5 . It is also noteworthy that diabetic gastric atony is similar to that observed after vagotomy 5 .Considering the extensive development of the myenteric plexus and its importance for the control of gastric and intestinal functions, and suspecting that diabetes may affect these neurons, in this way contributing to the gastric disturbances, we undertook the present study to determine ...

-We carried out this study with the purpose of analyzing the density of neurons of the myenteric plexus in the mesenteric, intermediate and antimesenteric regions of the ileum of rats. We conclude that there is a variation of neuronal density around the intestinal circumference and this fact independs on the technique used to stain the neurons, and that in a single region the neuronal density varies with the technique employed. We also call attention for the identification of the site were countings were carried out, so that the results of research in this area are not compromised.KEY WORDS: myenteric plexus, Giemsa, NADPH-diaphorase, NADH-diaphorase, acetylcholinesterase, rat, ileum.Diferenças regionais no número e tipo de neurônios mientéricos do íleo de ratos: comparação entre técnicas de evidenciação neuronal RESUMO -Realizamos este estudo com o objetivo de analisar a densidade de neurônios do plexo mientérico nas regiões mesentérica, intermediária e antimesentérica do íleo de ratos. Empregamos preparados de membrana corados por 4 diferentes técnicas. Através de contagens sob microscópio óptico em uma área de 8,96 mm 2 encontramos com as técnicas de Giemsa, histoquímica da NADH-diaforase, NADPH-diaforase e acetilcolinesterase, respectivamente as seguintes médias neuronais: região mesentérica 2144, 40±161,05, 1657,80±88,23, 473,80±19,62, 905,25±22,40; região intermediaria 1790,60±128,24, 1265,20±141,17, 371,30±27,84, 770,25±33,12; região antimesentérica 1647,0±76,67, 981,80±68,04, 298,50±22,75, 704,50±69,38. Concluimos que há uma variação na densidade neuronal ao redor da circunferência intestinal, e este fato independe da técnica utilizada para marcar os neurônios, e que em uma mesma região, a densidade neuronal varia com a técnica utilizada. Também chamamos a atenção para que seja indicado o local onde as quantificações serão realizadas, para que não haja comprometimento dos resultados em pesquisa nesta área.

The effect of vitamin E (1 g/kg body weight) supplementation on myosin-V and neuronal nitric oxide synthase (nNOS) immunoreactive myenteric neurons from the ileum of diabetic rats was investigated in the present study. Forty animals were divided into the following groups: normoglycemics (N), normoglycemics treated with vitamin E (NE), diabetics (D), and diabetics treated with vitamin E (DE). Quantitative and morphometric analyses were performed. The area of the tertiary plexus was also determined. Diabetes produced a 24% reduction in the number of myosin-V neurons in group D compared with group N, an effect that was accompanied by an increase in the tertiary plexus area (P < 0.05). Neuronal density was 27% higher in group NE than group N (P < 0.05). Nitrergic neuronal density was not altered as a consequence of either diabetes or vitamin E treatment. Myosin-V and nNOS immunoreactive neuronal cell body area increased significantly in group NE. The area of myosin-V and nNOS myenteric neurons also increased in group D. Vitamin E treatment (group DE) increased only the size of nitrergic neurons. The present results suggest that vitamin E elicited a neuroprotective and neurotrophic effect on the natural aging process, but with regard to diabetes, vitamin E supplementation exerted a neurotrophic effect only on nitrergic neurons.

-The aim of present study was to evaluate the number and basophily of cell bodies of myenteric neurons in the ileum of rats with diabetes mellitus induced by streptozotocin. Four groups of rats were used: diabetes was induced in two (D) whereas the other two worked as controls (N). Animals were sacrificed six (6N, 6D) or nineteen (19N, 19D) weeks after diabetes induction. A segment of the terminal portion of the ileum of each rat was obtained and stained with Giemsa's solution, for whole-mount preparation studies. Forty fields were analyzed in each animal, and the number and basophily intensity of cell bodies were recorded. After counting, the following mean numbers of neurons/mm 2 were obtained: 6N=593.1 ± 95.75, 6D=639.1 ± 130.8, 19N=580.1 ± 175.6 and 19D=402.0 ± 144.8. The analysis of basophily shown that highest frequency of neurons with weak/ intermediary basophily was verified in 6D group (55.3%), whereas the groups 6N, 19N e 19D presented 38%, 36% e 40% respectively. The statistical analysis showed that a long period is necessary to decrease the number of neurons/mm 2 in the rat ileum after diabetes induction, and that there was a reduction in basophily intensity in diabetic rats after 6 weeks of treatment, and such cells do not recover after a longer period (19 weeks).KEY WORDS: myenteric plexus, streptozotocin, diabetes mellitus, ileum.A duração do diabetes induzido por estreptozootocina é importante para determinar as mudanças no número e basofilia dos neurônios mientéricos RESUMO -O objetivo deste estudo foi avaliar o número e basofilia dos corpos celulares dos neurônios mientéricos no íleo de ratos com diabetes mellitus induzido por estreptozootocina. Quatro grupos de ratos foram usados. O diabetes foi induzido em dois grupos (D), enquanto outros dois eram controles (N). Os animais foram sacrificados 6 (6N, 6D) ou dezenove (19N, 19D) semanas após a indução do diabetes. Preparados totais de um segmento do íleo terminal, de cada rato, foram corados com solução de Giemsa. Foram contados 40 campos em cada animal, e o número e a intensidade de basofilia citoplasmática foram registrados. Após a contagem, as seguintes médias no número de neurônios/mm 2 foram obtidos: 6N=593,1 ± 95, 75, 6D=693,1 ± 130,8, 19N=580,1 ± 175,6 e 19D=402,0 ± 144,8. A análise da basofilia mostrou que a maior frequência de neurônios com basofilia fraca e intermediária foi verificada no grupo 6D (55,3%), enquanto os grupos 6N, 19N e 19D apresentaram 38%, 36% e 40% respectivamente. A análise estatística mostrou que um longo período é necessário para que ocorra a redução no número de neurônios/mm 2 no íleo de ratos, após a indução do diabetes. Também demonstrou uma redução na intensidade da basofilia citoplasmática 6 semanas de tratamento com estreptozootocina, e que estas células não se recuperam após um longo período de tempo (19 semanas). PALAVRAS-CHAVE: plexo mientérico, estreptozootocina, diabetes mellitus, íleo.Among the many effects of diabetes in the human gastrointestinal tract, those which affect the intestine are ...

-The purpose of this study was to verify the effects of proteic undernutrition on the neurons of the myenteric plexus from the duodenum of Wistar rats. Twenty-four animals at the age of 60 days were divided in four groups, which were named according to the period their mothers received hypoproteic ration (8%). Some segments of duodenum were subjected to histological treatment and stained with hematoxilin-eosin and some were used for whoie mount preparations stained with Giemsa. We observed small, medium-sized and large neurons grouped in ganglia of various shapes. It was concluded that the maternal proteic undernutrition does not affect the organization of the myenteric plexus and that animals submitted to undernutrition during gestation and lactation, when normally fed, show neurons with strongly basophilic cytoplasm and larger cellular bodies than those from control animals.KEY WORDS: myenteric neurons, proteic undernutrition, myenteric plexus.Efeitos da desnutrição proteica materna sobre os neurônios do plexo mientérico do duodeno de ratos RESUMO -O propósito deste estudo foi investigar os efeitos da desnutrição proteica sobre os neurônios do plexo mientérico do duodeno de ratos Wistar. Vinte e quatro animais com 60 dias de idade foram divididos em 4 grupos e denominados de acordo com o período em que suas mães receberam ração hipoproteica (8%). Alguns segmentos de duodeno foram submetidos a tratamento histológico e corados com hematoxilina-eosinae alguns foram utilizados na elaboração dos preparados de membrana corados com Giemsa. Observamos neurônios pequenos, médios e grandes formando gânglios de formatos diversos. Concluiu-se que a desnutrição proteica materna não afeta a organização do plexo mientérico e que animais desnutridos na gestação e lactação quando voltam a receber dieta com teor proteico normal apresentam neurônios com citoplasma fortemente basofílico e geralmente maiores que o de animais normo-alimentados. PALAVRAS-CHAVE: neurônios mientéricos, desnutrição proteica, plexo mientérico.When we look up the literature concerning proteic undernutrition on different parts of the organism, we find effects on the central nervous system 3 15 -26 -27 ,but few are the works concerned with the effects of undernutrition on the peripheral nervous system, and even rarer when the neurons of the myenteric plexus are involved, which are responsible for the intestinal motility. The myenteric plexus'has morphological and quantitative features that vary on the different parts of the intestinal gut in humans and animals 810,111316 -23 . A previous study of the small intestine of rats whose mothers were submitted to proteic deprivation during gestation 20 did not find alterations on the activity of the

-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% 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% 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.KEY WORDS: enteric neurons, proteic desnutrition, ascending colon, hematology, vitamin B.Efeitos da deficiência de proteínas e vitamina B sobre parâmetros sanguíneos e neurônios mioentéricos do colo de ratos adultos RESUMO -Os objetivos deste trabalho foram avaliar as repercussões da ingestão deficiente de proteínas e vitaminas do complexo B sobre parâmetros bioquímicos e hematológicos e neurônios mientéricos NADH e NADPH-diaforase positivos. Os animais controle (n=10) receberam ração comercial e os animais experimentais (n=10) ração com teor protéico reduzido para 8% durante 120 dias. Durante o sacrifício, coletou-se o sangue dos animais para avaliação de parâmetros sanguíneos e hematológicos e o colo ascendente para a análise quantitativa dos neurônios do plexo mioentérico. Observou-se que a redução do teor de proteínas na dieta para 8% associado a redução no teor de vitaminas do complexo B em ratos adultos, não causa alterações qualitativas e quantitativas das células sanguíneas das séries vermelha e branca, não leva a redução do valor da globulina nem a formação de edema ou ao surgimento de sinais clínicos característicos das carências de proteínas e vitaminas do complexo B. Por outro lado causa: menor ganho de peso corporal; alteração da composição corporal com acúmulo de gordura; redução nos valores de proteína total e albumina; redução na área do colo e evidenciação de densidade de neurônios nitrérgicos e NADH-diaforase positivos inferior ao esperado.PALAVRAS CHAVE: neurônios entéricos, desnutrição protéica, colo ascendente, hematologia, vitamina B. The utilization of animal models in studies of food restriction with known and controlled diets has as an advantage the improved knowledge about the many aspects of the human desnutrition 1 . Research on desnutrition aimsat simulating natural conditions, which involve deficienc...