Endomucin selectively regulates vascular endothelial growth factor receptor-2 endocytosis through its interaction with AP2.

The endothelial glycocalyx, located at the luminal surface of the endothelium, plays an important role in the regulation of leukocyte adhesion, vascular permeability, and vascular homeostasis. Endomucin (EMCN), a component of the endothelial glycocalyx, is a mucin-like transmembrane glycoprotein selectively expressed by venous and capillary endothelium. We have previously shown that knockdown of EMCN impairs retinal vascular development in vivo and vascular endothelial growth factor 165 isoform (VEGF165)-induced cell migration, proliferation, and tube formation by human retinal endothelial cells in vitro and that EMCN is essential for VEGF165-stimulated clathrin-mediated endocytosis and signaling of VEGF receptor 2 (VEGFR2). Clathrin-mediated endocytosis is an essential step in receptor signaling and is of paramount importance for a number of receptors for growth factors involved in angiogenesis. In this study, we further investigated the molecular mechanism underlying EMCN's involvement in the regulation of VEGF-induced endocytosis. In addition, we examined the specificity of EMCN's role in angiogenesis-related cell surface receptor tyrosine kinase endocytosis and signaling. We identified that EMCN interacts with AP2 complex, which is essential for clathrin-mediated endocytosis. Lack of EMCN did not affect clathrin recruitment to the AP2 complex following VEGF stimulation, but it is necessary for the interaction between VEGFR2 and the AP2 complex during endocytosis. EMCN does not inhibit VEGFR1 and FGFR1 internalization or their downstream activities since EMCN interacts with VEGFR2 but not VEGFR1 or FGFR1. Additionally, EMCN also regulates VEGF121-induced VEGFR2 phosphorylation and internalization.

Inflammation-induced sialin mediates nitrate efflux in dysfunctional endothelium affecting NO bioavailability.

AIM: The mechanism of NO bioavailability in endothelial dysfunction, the trigger for atherogenesis is still unclear as exogenous nitrate therapy fails to alleviate endothelial dysfunction. Recently, sialin, a nitrate transporter, has been linked to affect tissue nitrate/nitrite levels. Hence, we investigated the role of sialin in NO bioavailability in endothelial dysfunction. METHODS: Serum-starved HUVECs were stimulated with either TNFα or AT-2 for 24 h either alone or in the presence of autophagy inducer or autophagy inhibitor alone. Nitric oxide, nitrite, and nitrate levels were measured in cell supernatant and cell lysate. Quantitative real-time PCR, Annexin V-PI, and monocyte adhesion assays were performed. Immunofluorescence staining for sialin, vWF, and LC3 was performed. STRING database was used to create protein interacting partners for sialin. RESULTS: Sialin is strongly expressed in activated EC in vitro and atherosclerotic plaque as well as tumor neo-vessel ECs. Sialin mediates nitrate ion efflux and is negatively regulated by autophagy via mTOR pathway. Blocking sialin enhances NO bioavailability, autophagy, cell survival, and eNOS expression while decreasing monocyte adhesion. PPI shows LGALS8 to directly interact with sialin and regulate autophagy, cell-cell adhesion, and apoptosis. CONCLUSION: Sialin is a potential novel therapeutic target for treating endothelial dysfunction in atherosclerosis and cancer.

Differential Expression of Mucin in Salivary Gland Tumours.

Background and Objectives: Mucin has been implicated via various mechanisms in the development and growth of tumour cells. However, mucin expression studies in salivary gland tumours are limited, especially with samples from minor salivary glands. This study aims to investigate and compare mucin expression in benign and malignant salivary gland tumours of minor and major salivary gland origins. Materials and Methods: Special stains were used to stain neutral mucin (Periodic acid Schiff), sialomucin (Alcian Blue) and sulfomucin (Aldehyde Fuschin) within tissues from six normal salivary glands and 73 salivary gland tumours including 31 pleomorphic adenomas, 27 mucoepidermoid carcinomas, and 15 adenoid cystic carcinomas. A semi-quantitative approach was used to evaluate mucin expression within ductal lumens. Sialomucin was the most expressed mucin in all salivary gland tumours, regardless of origin. Results: A significant difference was observed in the mucin expression between benign and malignant salivary gland tumours, as pleomorphic adenoma showed three times significantly higher expression of sialomucin compared to mucoepidermoid carcinoma and adenoid cystic carcinoma (p = 0.028). Pleomorphic adenomas of major glands showed 42 times significantly higher expression of sialomucin compared to those of minor glands (p = 0.000). Conclusions: Sialomucin content in pleomorphic adenomas of major glands was vastly increased compared to that in minor glands. Differential sialomucin expression in benign and malignant salivary gland tumours suggests a role in diagnosing of borderline salivary gland tumours.

Tissue sulfomucin and sialomucin content in colon mucosa without intestinal transit subjected to intervention with Curcuma longa (curcumin)

Abstract Purpose: To measure the tissue sulfomucin and sialomucin content of the colon mucosa without fecal flow, subjected to intervention with curcumin, and the influence of the concentration used and the intervention time. Methods: Thirty-six rats were subjected to proximal right colostomy and distal mucous fistula. They were divided into two groups according to whether sacrifice was performed two or four weeks after the intervention. Each group was divided into three subgroups according to the enema applied daily: saline alone; curcumin at 50 mg/kg/day or curcumin at 200 mg/kg/day. Acid mucins were diagnosed using the Alcian blue technique. The mucin content was quantified by means of computer-assisted image analysis. The significance level of 5% was used throughout (p < 0.05). Results: There were dose-related increases in the quantities of sulfomucins in the animals subjected to interventions with curcumin, both after two weeks (p < 0.00001) and after four weeks (p < 0.00001). There were increases in sialomucin quantity that were concentration-related (p < 0.00001) and time-related (p < 0.00001). Conclusion: Curcumin enemas increase the quantity of acid mucins in the intestinal flow in the excluded colon, with dose and time dependency.

Análise morfométrica da parede intestinal e dinâmica de mucinas secretadas no jejuno de frangos suplementados com probiótico Bacillus subtilis cepa C3102 / Morphometric analysis of the intestinal wall and the dynamic of mucins secreted in the jejunum of broilers supplemented with Bacillus subtilis strain C3102

O objetivo deste estudo foi analisar a morfometria da parede intestinal e a dinâmica de mucinas secretadas no jejuno de frangos de corte suplementadas com probiótico Bacillus subtilis cepa C3102. Foram utilizados 720 pintinhos com um dia de vida, divididos em dois grupos: GA (Grupo controle) - aves alimentadas com ração sem suplementação de Bacillus subtilis cepa C3102 (1º ao 35º dia) e GB (Grupo tratado) - aves alimentadas com ração com suplementação de Bacillus subtilis cepa C3102 (1º ao 35º dia). Aos 7 e 35 dias 2cm do jejuno foram coletados e submetidos à rotina de processamento histológico. Cortes transversais de 1μm foram corados pela técnica do Alcian Blue (AB) para detecção de sialomucinas (pH 0,5) e sulfomucinas (pH 2,5), como também para contagem de células caliciformes presentes. A análise histoquímica revelou uma maior quantidade de sialomucinas presentes no jejuno dos animais que foram suplementados com probiótico Bacillus subtilis cepa C3102 (GB), quando comparados com os animais do grupo controle (GA). O número de células caliciformes presentes no grupo tratado (GB) foi superior ao grupo controle (GA).

The aim of this study was to analyze the morphology of the intestinal wall and the dynamics of mucins secreted in the jejunum of broilers supplemented with probiotic Bacillus subtilis strain C3102. We used 720 chicks with a day of life, divided into two groups: GA (control group) - birds fed diet without supplementation of Bacillus subtilis strain C3102 (1 to 35 days) and GB (treated group) - birds fed with supplementation of Bacillus subtilis strain C3102 (1 to 35 days). On the 7th and the 35th day, 2cm of jejunum were collected and submitted to histological processing. 1μm cross sections were stained by Alcian blue (AB) for detecting of sialomucins (pH 0.5) and sulphomucins (pH 2.5) as well as to count goblet cells. Histochemical analysis revealed a greater amount of sialomucins in the jejunum of animals that were supplemented with probiotic Bacillus subtilis strain C3102 (GB), when compared with the control group (GA). The number of goblet cells in the treated group (GB) was higher than the control group (GA).

Tissue content of sulfomucins and sialomucins in the colonic mucosa, without fecal stream, undergoing daily intervention with sucralfate

PURPOSE: To measure the content of acidic mucin, sialomucin, and sulfomucins in the colonic mucosa without fecal stream submit to intervention with sucralfate (SCF). METHODS: Thirty-six rats were submitted to a right colostomy and a distal mucous fistula and divided into two groups according to sacrifice to be performed two or four weeks. Each group was divided into three subgroups according daily application of enemas containing saline, SCF at 1.0 g/kg/day or 2.0 g/kg/day. Colitis was diagnosed by histological analysis. Acid mucins were determined with the Alcian-Blue and sulfomucin and sialomucin by high iron diamine-alcian blue (HID-AB) techniques. The mucins were quantified by computer-assisted image analysis. Mann-Whitney and ANOVA tests were used to analyze the results establishing the level of significance of 5% for both (p<0.05). RESULTS: SCF enemas decreased the inflammation score and was related to the concentration used and time of the intervention. SCF at both concentrations increased the content of acid mucin, which was related to the concentration used and to the improvement in the inflammatory score. There was an increase in the content of sulfomucins and sialomucins in SCF groups. SCF increased sulfomucins from 2 weeks of intervention, which was not related to the dose or time of application. The increase in sialomucin content was related to the time and dose used in the intervention. CONCLUSION: Sucralfate increased the content of acidic mucins, primarily at the expense of sialomucin, which was affected by the dose and time of intervention. .

Quantification by computerized morphometry of tissue levels of sulfomucins and sialomucins in diversion colitis in rats / Quantificação por morfometria computadorizada dos níveis teciduais de sulfomucinas e sialomucinas na colite de exclusão em ratos

PURPOSE: To quantify the intensity of sulfomucin and sialomucin expression in the colon mucosa, by means of computer-assisted image processing, comparing segments with and without fecal stream and correlating with the duration of fecal transit exclusion. METHODS: Forty-five Wistar rats were subjected to diversion of the fecal stream in the left colon by means of constructing a proximal colostomy and distal mucosal fistula. They were distributed randomly into three experimental groups of 15 animals, of which 10 were subjected to colon diversion (experimental subgroup) and five were only subjected to laparotomy, without colon diversion (control subgroup). The three experimental groups were formed according to the sacrifice date, which was to be performed six weeks after the surgical procedure (Group A), 12 weeks (Group B) and 18 weeks (Group C). The sulfomucin and sialomucin expression in the colon mucosa was evaluated using the histochemical technique of high iron diamine-alcian blue (HID-AB). The tissue expression was quantified for each animal, in the segments with and without fecal stream, at a location where there were four complete contiguous crypts in two random fields, with the aid of the computer-assisted image analysis software. The final value was taken to be the mean reading from the two fields selected, in the segments with and without fecal stream. To compare the expressions of the two mucin subtypes in the segments with and without fecal stream, the paired Student t test was used. To analyze variance according to duration of exclusion, ANOVA with the Newman-Keuls post-test was used, setting the significance level at 5 percent (p<0.05). RESULTS: There were significant reductions in tissue sulfomucin and sialomucin content in the colon without fecal stream, independent of the duration of exclusion considered. There was increased tissue sulfomucin content and decreased tissue sialomucin in the segments without fecal stream, ...

OBJETIVO: Quantificar, por meio de processamento de imagem assistida por computador, a intensidade de expressão de sulfomucinas e sialomucinas na mucosa cólica comparando segmentos com e sem trânsito e relacionando-a ao tempo de exclusão de trânsito fecal. MÉTODOS: Quarenta e cinco ratos Wistar machos foram submetidos à derivação do trânsito no cólon esquerdo pela confecção de colostomia proximal e fístula mucosa distal. Foram divididos de forma randomizada em três grupos experimentais de 15 animais, nos quais 10 foram submetidos à derivação do trânsito cólico (subgrupo experimental) e cinco somente a laparotomia exploradora sem desvio do trânsito fecal (subgrupo controle). Os três grupos experimentais foram formados segundo o sacrifício ter sido realizado em seis (grupo A), 12 (Grupo B) e 18 semanas (Grupo C). A avaliação da expressão de sulfomucinas e sialomucinas na mucosa cólica foi realizada pela técnica histoquímica da diamina de ferro alto alcian-blue (HID-AB). A quantificação da expressão tecidual foi determinada, para cada animal, nos segmentos com e sem trânsito, em local onde existiam quatro criptas contíguas e íntegras em dois campos aleatórios com auxílio de programa de análise de imagem assistida por computador. Adotou-se como valor final a média das leituras dos dois campos selecionados, nos segmentos providos e desprovidos de trânsito fecal. Na comparação entre a expressão dos dois subtipos de mucinas nos segmentos com e sem trânsito fecal utilizou-se o teste t de Student pareado. Para análise de variância segundo o tempo de exclusão utilizou-se o teste de ANOVA com o pós-teste de Newmann-Keuls, estabelecendo-se nível de significância de 5 por cento (p<0,05). RESULTADOS: Houve redução significante no conteúdo tecidual de sulfomucinas e sialomucinas no cólon desprovido de trânsito fecal, independente do tempo de exclusão considerado. Houve aumento no conteúdo tecidual de sulfomucinas e diminuição de sialomucinas nos segmentos ...

Tissue quantification of neutral and acid mucins in the mucosa of the colon with and without fecal stream in rats / Quantificação tecidual de mucinas neutras e ácidas na mucosa do cólon com e sem trânsito intestinal em ratos

PURPOSE: To quantify the intensity of the expression of neutral and acids mucins in mucosa of the colon with and without fecal stream and to correlate this with the duration of fecal transit diversion. METHODS: Thirty male Wistar rats were subjected to fecal transit deviation in the left colon by a proximal colostomy and a distal mucous fistula. The animals were divided into three experimental groups, according to whether sacrificing would be performed six, 12 or 18 weeks after surgery. The expression of neutral and acid mucins was evaluated using the histochemical techniques of Periodic Acid Schiff and Alcian Blue, respectively. The tissue mucins expression was quantified by computer-assisted image analysis software (NIS-Elements) in the segments with and without fecal stream. Student's paired t test was used to compare the quantities of mucins in colon with or without fecal stream and variance between the experimental groups by ANOVA and Newman-Keuls post-test, establishing level of signification of 5 percent (p<0.05). RESULTS: There were significant decreased quantities of acid and neutral mucins in the colon without transit, compared with the colon with fecal stream, independent of the duration of exclusion. There was increased expression of neutral mucins in the colon with fecal stream after 12 and 18 weeks of exclusion. There was no increase in the expression of acid mucins in the colon with transit as the duration of fecal transit exclusion progressed. There was increased production of acid mucins in the animals submitted to diversion of the fecal stream for 18 weeks, compared with those subjected to diversion for 6 and 12 weeks. In the colon without fecal stream, there was increased expression of neutral mucins after 12 and 18 weeks of exclusion. CONCLUSIONS: Deviation of the fecal stream decreased the expression of acid and neutral mucins in the segments without fecal transit, compared with segments with transit. Regardless of ...

OBJETIVO: Quantificar a intensidade de expressão de mucinas neutras e ácidas na mucosa cólica provida e desprovida de trânsito intestinal relacionando-a ao tempo de exclusão fecal. MÉTODOS: Trinta ratos Wistar machos foram submetidos à derivação do trânsito no cólon esquerdo por colostomia proximal e fístula mucosa distal. Os animais foram divididos em três grupos experimentais segundo o sacrifício ter sido realizado seis, 12 e 18 semanas após a cirurgia. A avaliação da expressão de mucinas neutras e ácidas na mucosa cólica foi realizada com as técnicas histoquímicas do Periódico Ácido de Schiff e Azul de Alcian, respectivamente. A quantificação da expressão tecidual das mucinas foi com auxílio de programa de análise de imagem assistida por computador (NIS-Elements) nos segmentos providos e desprovidos de trânsito fecal. Utilizou-se o teste t de Student pareado na comparação da expressão de mucinas nos segmentos com e sem trânsito e a variação na expressão entre os grupos experimentais pelo teste ANOVA e pós-teste de Newmann-Keuls, estabelecendo-se nível de significância de 5 por cento (p<0,05). RESULTADOS: Houve redução na quantidade de mucinas neutras e ácidas no cólon desprovido de trânsito quando comparado ao cólon provido de trânsito, independente do tempo de exclusão. Ocorreu aumento na expressão de mucinas neutras no cólon provido de trânsito intestinal após 12 e 18 semanas de exclusão. Não houve aumento na expressão de mucinas ácidas no cólon provido de trânsito com o progredir do tempo exclusão de trânsito fecal. Ocorreu aumento na produção de mucinas ácidas nos segmentos com exclusão de trânsito por 18 semanas quando comparados aos animais submetidos à exclusão por seis e 12 semanas. No cólon desprovido de trânsito ocorreu aumento na expressão de mucinas neutras após 12 e 18 semanas de exclusão. CONCLUSÕES: A derivação do trânsito fecal diminui a expressão de mucinas ácidas e neutras nos segmentos desprovidos de trânsito fecal ...

Early morphological and histochemical alterations in rats subjected to ileocystoplasty / Alterações morfológicas e histoquímicas precoces em ratos submetidos à ileocistoplastia

PURPOSE: To study morphologic and histochemical alterations arising at the ileocystoplasty site. METHODS: Sixteen Wistar female rats were subjected to ileocystoplasty and sacrificed after eight weeks. Material collected was divided into four groups for histological and histochemical studies: Group I (control) - isolated ileum segment removed during ileocystoplasty; Group II - ileoileal anastomosis; Group III - ileovesical anastomosis and Group IV - ileal segment from the neobladder. Histological and histochemical study assessed dysplasia, metaplasia, acute and chronic inflammation, fibrosis, atrophy, hypertrophy, total mucins, sialomucins and sulfomucins. The non-parametric Wilcoxon and Mann-Whitney tests were employed in statistical analysis. RESULTS: None of the groups presented dysplasia. Acute inflammation and atrophy occurred in Groups II, III and IV, not reaching statistical significance. Metaplasia was significant only in Group III (p=0.012). Chronic inflammation, fibrosis and hypertrophy were significant in Groups II, III and IV. There was a significant increase in total mucin content in Group IV (p=0.014) and a reduction in Group III (p=0.016). Increases in sialomucins were observed in samples for Groups III (p=0.003) and IV (p=0.002) along with reduced sulfomucins in samples from Groups III (p=0.013) and IV (p=0.008). CONCLUSION: Ileocystoplasty in female rats caused squamous metaplasia, chronic inflammatory infiltration, fibrosis, hypertrophy, increase in sialomucin content, reduction in sulfomucins, and alterations in total mucin content with statistical significance, as well acute inflammatory infiltration and muscular atrophy with less intensity.

OBJETIVO: Estudar alterações morfológicas e histoquímicas nas ileocistoplastias em ratos fêmea. MÉTODOS: 16 ratos fêmea foram submetidos à ileocistoplastia, sacrificadas após oito semanas. O material coletado foi e dividido em quatro grupos para análise morfológica e histoquímica: Grupo I (controle) biópsia intestinal no momento da cirurgia; Grupo II - anastomose íleo-ileal; Grupo III - anastomose íleo-vesical e Grupo IV - segmento intestinal da neobexiga. Os parâmetros avaliados foram: displasia, metaplasia, processo inflamatório agudo e crônico, fibrose, atrofia, hipertrofia, conteúdo total de mucinas, sialomucinas e sulfomucinas. Utilizou-se os testes não-paramétricos de Wilcoxon e Mann-Whitney para estudo estatístico. RESULTADOS: Não houve displasia. Processo inflamatório agudo e atrofia ocorreram nos grupos II, III e IV, sem significância estatística. Metaplasia com significância estatística ocorreu somente no grupo III (p=0.012). Processo inflamatório crônico, fibrose e hipertrofia foram significantes nos grupos II, III e IV. Observou-se aumento significante no conteúdo total de mucinas no grupo IV (p=0.014) e redução no grupo III (p=0.013). Aumento significante de sialomucinas foi observado nos grupos III (p=0.003) e IV (p=0.002) e redução significante das sulfomucinas nos grupos III (p=0.013) e IV (p=0.008). CONCLUSÃO: Nas ileocistoplastias em ratos fêmea observou-se metaplasia escamosa, processo inflamatório crônico, fibrose, hipertrofia, aumento do conteúdo de sialomucinas, redução das sulfomucinas e alterações no conteúdo total de mucinas com significância estatística, bem como atrofia e processo inflamatório agudo em menor intensidade.

A inter-relação das sialomucinas (antígenos Tn e Stn) com o adenocarcinoma no esôfago de Barrett / Relationship of the sialomucins (Tn and Stn antigens) with adenocarcinoma in Barrett's esophagus

OBJETIVO: O esôfago de Barrett (EB) é conseqüência do refluxo gastroesofágico crônico e considerado fator de risco para o desenvolvimento de adenocarcinoma. Estudos do muco, em especial das mucinas ácidas representadas pelas sialomucinas presentes nas células caliciformes, mostraram que na metaplasia do tipo intestinal, o epitélio do órgão pode expressar antígenos denominados Tn e Stn. Estes antígenos já foram analisados em tumores gástricos e colônicos, porém não foram encontradas referências à sua utilização no EB. Este trabalho objetivou analisar estes antígenos em doentes com EB e em adenocarcinoma associado ao EB. MÉTODOS: Foram estudados, utilizando testes imunohistoquímicos, os antígenos Tn e Stn, nas biópsias endoscópicas de 29 doentes com EB, sete com adenocarcinoma no EB, além de oito indivíduos com epitélio esofágico normal. RESULTADOS: Nas células caliciformes, foi observada positividade para Stn em 100 por cento dos casos e para Tn em 48 por cento dos casos. Nas células colunares, o Stn foi sempre negativo, enquanto o Tn foi positivo em 100 por cento dos casos. Entretanto, nos doentes com adenocarcinoma no EB, a positividade para ambos os antígenos foi de 100 por cento. Nos indivíduos normais, houve positividade para o antígeno Tn e negatividade para Stn em todos os casos (100 por cento). CONCLUSÃO: É provável que nos doentes com EB a positividade para o Tn, à semelhança do ocorrido quanto à positividade do mesmo antígeno nos portadores de adenocarcinoma, possa significar maior suscetibilidade para ocorrência futura de câncer. Assim, a pesquisa das sialomucinas poderá ser rotineiramente utilizada, contribuindo como fator prognóstico para desenvolvimento de adenocarcinoma no EB.

OBJECIVE: Barrett's esophagus (BE) is a consequence of chronic gastroesophageal reflux and is considered a risk factor for adenocarcinoma. The study of the mucus, especially acid mucins, such as the sialomucins in the goblet cells which characterize BE, showed that in intestinal metaplasia, frequent in the digestive tract, the organ's original epithelium could express Tn and Stn antigens. These antigens have already been detected in gastric and colonic tumors, however references in BE were not found. This research aimed to analyze these antigens in patients with BE and in adenocarcinoma associated with BE. METHODS: Utilizing immunohistochemistry tests, Tn and Stn antigens were studied in the endoscopic biopsies of 29 patients with BE and seven with adenocarcinoma in BE, as well as eight individuals with normal esophageal epithelium at upper digestive endoscopy.. RESULTS: The Stn antigen was positive in the goblet cells of patients with BE in 100 percent of the cases and the Tn was positive in 48 percent. In the columnar cells, Stn was always negative, while Tn was positive in 100 percent of the cases. However, in adenocarcinoma in BE, both antigens were 100 percent positive. In normal individuals, the Tn antigen was positive and the antigen Stn negative in all cases. CONCLUSION: It is probable that the BE group in which the Tn antigens in the goblet cells are positive, similarly to the same antigen in the adenocarcinoma group, might indicate a higher susceptibility for potential occurrence of cancer. In the future, trials with sialomucins could be used routinely, thereby contributing as a prognostic factor of adenocarcinoma in BE.

Histological and histochemical changes of the intestinal mucosa at the urothelial-enteric anastomotic site

OBJECTIVE: The incorporation of bowel segments for urinary tract reconstruction may induce intestinal mucosal changes with the development of metabolic, nutritional, gastrointestinal and carcinogenic complications. The early histological and histochemical changes of the intestinal mucosa in contact with the feces-urine mixture, are evaluated in the present study. MATERIALS AND METHODS: Twelve rats (operated group) were submitted to a vesico-colonic anastomosis, and 10 rats (control group) underwent a sham operation (the colon was opened and immediately sutured). On the operated group, the left colon was divided into 3 equal portions and the middle segment was used for the bladder-colonic anastomosis. After 20 weeks, the animals were sacrificed and the entire left colon in each group, as well as the bladder and the vesico-colonic anastomosis in the operated group, was removed. The proximal, middle (anastomotic site in the operated group and sutured portion in the control group) and distal colon were used for histological and histochemical studies. RESULTS: Metaplasia, chronic inflammatory process and fibrosis were significantly greater at the anastomotic site compared to the middle segment of the control group. There were no differences in both groups in terms of dysplasia, atrophy and hypertrophy either on the proximal, middle or anastomotic area and distal portion of the left colon. All animals in the operated group showed a reduced presence of sulfomucin and an increase in the sialomucin content. CONCLUSION: The histological changes observed in this study may suggest a precancerous phenomenon.

Mucinas del aparato genital masculino de la baba (caiman crocodilus crocodilus) / Mucins of the male genital tract of the spectacled cayman (caiman crocodilus crocodilus)

Se realizó el estudio histoquímico de mucinas en las vías espermáticas de nueve babas adultas, utilizando las coloraciones Hematoxilina-Eosina, PAS, PAS-Digerido (Diastasa) y PAS-Azul de Alcian a pH 1,0 y 2,5. Los hallazgos encontrados fueron: reacción PAS. positiva en el epidídimo caudal; reacción positiva a PAS y PAS-Azul de Alcian a pH 2,5 y 1,0 en el colículo seminal, surco eyaculador del pene y superficie dorsal del pene, evidenciando la presencia de mucinas neutras, sialomucinas y sulfomucinas, respectivamente; reacción positiva a PAS y PAS-Azul de Alcian a pH 2,5 en la superficie dorsal y ventral del pene, evidenciando la presencia de mucinas neutras y sialomucinas. Se analizan las posibles correlaciones fisiológicas, tomando en cuenta la ausencia de glándulas sexuales anexas en esta especie.