ABSTRACT
Boron is an essential element for life and intake via different sources into the body. Because effects of boron and compounds on the body has not been studied enough especially in tissue level, we planned this study to evaluate the effects of borax the most intaken form of boron compound on different intraabdominal organs histologically and also clinically. 42 male rats divided into equal 7 groups and different toxicological doses consistent with its LD50 dose (5000 mg/kg/d) were administered by gavage except control and sham groups. In the study, 2 different kinds of borax one of which was produced for research and the other for agriculture but the same formulation, were used and their effects were also compared. As a result it was found that borax did not cause any histological changes in kidney, large intestine, liver and stomach in lower doses. But if doses were increased, a slightly inflammatory cell migration was detected without clinical signs in liver and large intestine. However, when a single very high dose of borax was administered, very high edema, inflammatory cell migration and neovascularization was observed and clinically 2 out of 6 rats died within 5 hours. We suggested that very high dose intake of borax may cause sudden death and also during long periods and higher dose intake may pave the way of inflammatory bowel diseases. At the same time, in boron related studies we advice that the kind of boron and also their source should be evaluated carefully and the most suitable compound should be chosen in case of faulty results.
El boro es un elemento esencial para la vida e ingresa a través de diferentes fuentes al cuerpo. Dado que los efectos del boro y sus compuestos en el cuerpo no se han estudiado lo suficiente, especialmente a nivel tisular, se planificó este estudio para evaluar sus efectos y la forma de consumo más común del compuesto de boro sobre diferentes órganos intraabdominales a nivel histológico y clínico. Cuarenta y dos ratas macho divididas en 7 grupos, con diferentes dosis toxicológicas de acuerdo con su dosis DL50 (5000 mg/kg/d) administradas por sonda, excepto en los grupos control y simulado. En el estudio fueron usados 2 tipos diferentes de boro, uno producido para la investigación y el otro para la agricultura, pero de la misma formulación, y sus efectos fueron comparados. Se encontró que el boro no causó cambios histológicos en el riñón, intestino grueso, hígado y estómago en dosis bajas. Sin embargo, al aumentar la dosis, se detectó una leve migración de células inflamatorias, sin signos clínicos, en el hígado e intestino grueso. Por otra parte, cuando se administró una sola dosis muy alta de boro, se observó un amplio edema, migración de células inflamatorias y neovascularización; clínicamente 2 de 6 ratas murieron dentro de 5 horas. Sugerimos que la ingesta de dosis muy altas de bórax pueden causar la muerte súbita, además la ingesta de dosis altas y durante periodos de tiempo prolongado puede causar enfermedades inflamatorias del intestino. Es recomendable que en los estudios relacionados con el boro, el tipo de boro así como su fuente sean evaluados cuidadosamente, eligiendo el compuesto más adecuado en caso de resultados erróneos.
Subject(s)
Animals , Male , Rats , Boron/toxicity , Digestive System/drug effects , Digestive System/pathology , Intestine, Large/drug effects , Intestine, Large/pathology , Kidney/drug effects , Kidney/pathology , Liver/drug effects , Liver/pathology , Rats, Sprague-Dawley , Stomach/drug effects , Stomach/pathologyABSTRACT
PURPOSE: To analyse histopathological alterations characterized by the mitotic index in the mucosa of the large intestine in Wistar rats submitted to jejunoileal bypass operation after continued administration of sodium nitrite and vitamin C to different groups. METHODS: Eighty male Wistar rats were employed and separated into 12 groups. In the control group (20 rats): five animals ingested only water; five animals received vitamin C; five animals received sodium nitrite and five received sodium nitrite + vitamin C. In the sham group (20 rats), the animals were anesthetized and underwent midline laparotomy and only intestinal manipulation was performed: five animals ingested only water; five animals received vitamin C; five animals received sodium nitrite and five received sodium nitrite + vitamin C. In the operated group 40 rats underwent a jejunoileal bypass surgery: ten animals ingested only water; ten animals received vitamin C; ten animals received sodium nitrite and ten received sodium nitrite + vitamin C. The mean weight of the animals was measured weekly. The large intestine was subdivided into cecum (S1), ascending colon (S2), transverse colon (S3), descending colon (S4) and rectum (S5) for histopathological analysis and mitotic counts. The statistical analysis was used to compare the mitotic indices. The level of significance was 5%. RESULTS: The mean of all the segments indicates that the sodium nitrite+vitamin C group obtained the lowest mitotic index compared to the other treatments in the control group. The segments S1 and S2 showed a statistical difference with the vitamin C treatment: a higher mitotic index and better preservation of the mucosa in the operated group. In the sham group the main statistical difference occurred only in the sodium nitrite+vitamin C group between the means of the segments. CONCLUSIONS: The comparison of all the colonic segments of the various groups revealed a lower mitotic index in the animals treated with sodium nitrite+vitamin C. In addition, it was found that vitamin C did not present a statistically significant inhibiting effect on the preservation of the mucosa and the mitotic index.
OBJETIVO: Analisar as alterações histopatológicas caracterizada pelo índice mitótico na mucosa do intestino grosso em ratos Wistar submetidos a operação de bypass jejunoileal após a administração continuada de nitrito de sódio e vitamina C para diferentes grupos. MÉTODOS: Oitenta ratos Wistar foram utilizados e separados em 12 grupos. No grupo controle (20 ratos): cinco animais ingeriram apenas água; cinco animais receberam vitamina C, cinco animais receberam nitrito de sódio e cinco receberam nitrito de sódio + vitamina C. No grupo sham (20 ratos), os animais foram anestesiados e submetidos a laparotomia mediana e só a manipulação intestinal foi realizada: cinco animais ingeriram apenas água; cinco animais receberam vitamina C, cinco animais receberam nitrito de sódio e cinco receberam nitrito de sódio + vitamina C. No grupo operado 40 ratos foram submetidos a uma cirurgia de bypass jejunoileal: dez animais ingeridos apenas água; dez animais receberam vitamina C, dez animais receberam nitrito de sódio e dez nitrito de sódio + vitamina C. O peso médio dos animais foi medido semanalmente. O intestino grosso foi subdividido em ceco (S1), cólon ascendente (S2), cólon transverso (S3), cólon descendente (S4) e reto (S5) para análise histopatológica e contagem das mitoses. A análise estatística foi utilizado para comparar os índices mitóticos. O nível de significância foi de 5%. RESULTADOS: A média de todos os segmentos indica que o grupo que ingeriu nitrito de sódio + vitamina C obteve o menor índice mitótico em relação aos demais tratamentos no grupo controle. Os segmentos S1 e S2 mostraram uma diferença estatística com a vitamina C de tratamento: um maior índice mitótico e melhor preservação da mucosa no grupo operado. No grupo sham a principal diferença estatística ocorreu apenas no grupo que ingeriu nitrito de sódio + vitamina C entre as médias dos segmentos. CONCLUSÕES: A comparação de todos os segmentos do colon dos vários grupos revelaram um menor índice de mitose nos animais tratados com nitrito de sódio + vitamina C. Além disso, a vitamina C não apresentou efeito inibidor, estatísticamente significativo, na preservação da mucosa e do índice de mitoses.
Subject(s)
Animals , Male , Rats , Ascorbic Acid/pharmacology , Food Preservatives/pharmacology , Intestine, Large/pathology , Jejunoileal Bypass/adverse effects , Mitosis/drug effects , Sodium Nitrite/pharmacology , Antioxidants/pharmacology , Intestinal Mucosa/drug effects , Intestinal Mucosa/pathology , Intestine, Large/drug effects , Mitotic Index , Mitosis/physiology , Rats, WistarABSTRACT
MK-212 (1 x 10(-7)M -- 1 x 10(-5)M) produced dose-dependent contractions of guinea pig ileum, taenia coil and rat fundus strip. The responses to MK-212 in all three preparations were blocked competitively by cyproheptadine (1 x 10(-8)M) a 5-HT receptor antagonist. Mepyramine (1 x 10(-8)M)-H1 receptor antagonist also inhibited competitively the responses of guinea pig ileum and taenia coli to MK-212. However, it failed to block significantly the responses of rat fundus strip to MK-212. Metiamide (1 x 10(-6)M), propranolol (1 x 10(-6)M) or atropine (1 x 10(-6)M) did not produce any significant effects on MK-212 induced contractile responses of guinea pig ileum, taenia coli and rat fundus strip. Our findings suggest that MK-212 produces both 5-HT as well as histamine like effects on the guinea-pig ileum, taenia coli and rat fundus strip.