PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Alves G.E.S., Mendes H.M.F., Alves T.G.S., Faleiros R.R., Vasconcelos A.C., Santos R.L. & Rio Tinto J.J.M. 2011. Hydrocortisone decreases apoptosis in jejunum of horses subjected to experimental ischemia and reperfusion. Pesquisa Veterinária Brasileira 31(6):471-476. Departamento de Clínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, MG 31270-901, Brazil. E-mail: geraldo@vet.ufmg.br In order to evaluate the effect of hydrocortisone on apoptosis in the jejunum of horses subjected to ischemia and reperfusion, ten horses were paired and grouped into two groups - treated (n=5) and non treated (n=5). Segments of the jejunum were used as controls (C), or as venous ischemia (VIsc), which were subjected to 2h of ischemia followed by 2 or 12h of reperfusion. C samples were collected at time zero (prior to ischemia) and VIsc samples were collected at 2h of ischemia and at 2 and 12h of reperfusion. TUNEL positive apoptotic cells were counted in 10 microscopical fields in deep mucosa from each horse throughout the time course. After 12h of reperfusion, the number of apoptotic cells in treated group were significantly lower than in untreated animals, indicating that hydrocortisone inhibits apoptosis. These results indicate that hydrocortisone has a beneficial effects favoring the maintenance of jejunal integrity in horses with ischemia and reperfusion injuries by preventing apoptotic cell death.

• Hydrocortisone ischemia reperfusion apopitosis isquemia reperfusão apopitose

Abstract in Portuguese:

RESUMO.- Alves G.E.S., Mendes H.M.F., Alves T.G.S., Faleiros R.R., Vasconcelos A.C., Santos R.L. & Rio Tinto J.J.M. 2011. Hydrocortisone decreases apoptosis in jejunum of horses subjected to experimental ischemia and reperfusion. [Hidrocortisona diminui a apoptose no jejuno de equinos sujeitos a isquemia e reperfusão experimentais.] Pesquisa Veterinária Brasileira 31(6):471-476. Departamento de Clínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, MG 31270-901, Brazil. E-mail: geraldo@vet.ufmg.br Com o objetivo de avaliar o efeito da hidrocortisona sobre a apoptose no jejuno de equinos submetidos à is-quemia e reperfusão, dez cavalos foram agrupados em dois grupos: tratado (n=5) e não-tratado (n=5). Foi utilizado um segmento do jejuno como controle (C) e outro foi submetido a isquemia venosa (VIsc) por 2h seguida de 2 ou 12 h de re-perfusão. Amostras de C foram coletadas no tempo zero (antes da isquemia) e amostras de VIsc foram coletadas após 2h de isquemia e a 2 e 12h de reperfusão. Células apoptóticas TUNEL positivas foram contadas em 10 campos microscópicos da mucosa na região das criptas de cada animal em cada tempo. Após 12h de reperfusão, o número de células apoptóticas no grupo tratado foram significativamente menores do que no grupo não-tratado, indicando que a hidrocortiso-na inibe a apoptose. Esses resultados mostram que a hidro-cortisona tem efeito benéfico favorecendo a manutenção da integridade do jejuno em cavalos com lesão de isquemia e reperfusão por prevenir a morte celular por apoptose.

Abstract in English:

ABSTRACT.- Mendes H.M.F., Faleiros R.R., Vasconcelos A.C., Alves G.E.S. & Moore R.M. 2009. [Apoptosis in equine small colon subjected to experimental ischemia and reperfusion.] Apoptose no cólon menor eqüino submetido à isquemia e reperfusão experimentais. Pesquisa Veterinária Brasileira 29(3):198-204. Departamento de Clínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, Pampulha, Belo Horizonte, MG 31270-901, Brazil. E-mail: faleiros@ufmg.br Intestinal ischemia and reperfusion are important factors for mortality in horses. The objective of this study was to detect and to quantify apoptosis in the mucosa of equine small colon in a model of ischemia and reperfusion. The small colon was surgically exposed in twelve horses, and two intestinal segments were demarcated and subjected to 90 (SI) or 180 (SII) minutes of complete arteriovenous ischemia. Intestinal samples were collected before ischemia (control), at its end and after 90 and 180 minutes of reperfusion. Samples were histological processed and stained by hematoxylin and eosin (SI and SII) and by the technique of TUNEL (SI). Digitized histological images were analyzed morphometrically to detect apoptotic cells and to determine the apoptotic index (AI). After 90 or 180 minutes of arteriovenous ischemia, an increase in apoptotic cells was verified when compared with the control group, although no difference could be detected between the different periods of ischemia (P<0.05). After the first 90 minutes of reperfusion, a decrease in AI occurred, similar in both segments, possibly due to lack of energy source promoted by ischemia. AI was maximized after 180 minutes of reperfusion (sample harvested only in SI) (P<0.05). In conclusion, apoptosis is an important cause of cellular mucosal death in equine small colon ischemic obstruction, occurring early in ischemia, and later (after 90 minutes) in the reperfusion period.

• Horse small colon apoptosis ischemia and reperfusion

Abstract in Portuguese:

ABSTRACT.- Mendes H.M.F., Faleiros R.R., Vasconcelos A.C., Alves G.E.S. & Moore R.M. 2009. [Apoptosis in equine small colon subjected to experimental ischemia and reperfusion.] Apoptose no cólon menor eqüino submetido à isquemia e reperfusão experimentais. Pesquisa Veterinária Brasileira 29(3):198-204. Departamento de Clínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, Pampulha, Belo Horizonte, MG 31270-901, Brazil. E-mail: faleiros@ufmg.br Intestinal ischemia and reperfusion are important factors for mortality in horses. The objective of this study was to detect and to quantify apoptosis in the mucosa of equine small colon in a model of ischemia and reperfusion. The small colon was surgically exposed in twelve horses, and two intestinal segments were demarcated and subjected to 90 (SI) or 180 (SII) minutes of complete arteriovenous ischemia. Intestinal samples were collected before ischemia (control), at its end and after 90 and 180 minutes of reperfusion. Samples were histological processed and stained by hematoxylin and eosin (SI and SII) and by the technique of TUNEL (SI). Digitized histological images were analyzed morphometrically to detect apoptotic cells and to determine the apoptotic index (AI). After 90 or 180 minutes of arteriovenous ischemia, an increase in apoptotic cells was verified when compared with the control group, although no difference could be detected between the different periods of ischemia (P<0.05). After the first 90 minutes of reperfusion, a decrease in AI occurred, similar in both segments, possibly due to lack of energy source promoted by ischemia. AI was maximized after 180 minutes of reperfusion (sample harvested only in SI) (P<0.05). In conclusion, apoptosis is an important cause of cellular mucosal death in equine small colon ischemic obstruction, occurring early in ischemia, and later (after 90 minutes) in the reperfusion period.