RESUMEN
In randomized groups of Wistar rats, the effect inhibitor of selective NASAID over the COX-1, COX-2 and COX-3 the synchronizes inhibition of COX-1 and COX-2, COX-1 and COX-3, COX-2 and COX-3, and COX-1, COX-2 and COX-3 were studied. The conclusions were that the selective inhibition of COX-1, COX-2 and COX-3 no given gastrointestinal damage; the synchronizes inhibition of COX-1 and COX-2 given preferential gastric damage; in contrast the inhibition of COX-2 and COX-3 given massive necrosis preferential in small intestine.(AU)
Asunto(s)
Animales , Femenino , Ratas , /efectos adversos , Inhibidores de la Ciclooxigenasa , Tracto Gastrointestinal/efectos de los fármacos , Isoenzimas/antagonistas & inhibidores , Prostaglandina-Endoperóxido Sintasas , Tracto Gastrointestinal/enzimología , Tracto Gastrointestinal/patología , Enfermedades Gastrointestinales/inducido químicamente , Enfermedades Gastrointestinales/enzimologíaRESUMEN
In randomized groups of Wistar rats, the effect inhibitor of selective NASAID over the COX-1, COX-2 and COX-3 the synchronizes inhibition of COX-1 and COX-2, COX-1 and COX-3, COX-2 and COX-3, and COX-1, COX-2 and COX-3 were studied. The conclusions were that the selective inhibition of COX-1, COX-2 and COX-3 no given gastrointestinal damage; the synchronizes inhibition of COX-1 and COX-2 given preferential gastric damage; in contrast the inhibition of COX-2 and COX-3 given massive necrosis preferential in small intestine.
RESUMEN
Five experimental models were carried out in different groups of Wistar rats (n = 15) in order to study selective (cyclo-oxygenase) COX-2 non-steroid antiinflammatory inhibitors, such as celecoxib and rofecoxib, as follows: 1) Dose-dependent oral celecoxib and rofecoxib for 5 days, and 24 hours after oral indomethacin. 2) Same as 1, but subcutaneously. 3) Gastric ulcer induced by means of glacial acetic acid. 4) Duodenal ulcer induced by means of cysteamine. 5) Stress due to being kept under restraint and immersion in water at 15 degrees C for 6 hours. Celecoxib and rofecoxib, either orally or subcutaneously, did not produce necrotic injuries in healthy gastrointestinal mucosa (0
), showing normal histology. On the other hand, the injuries previously induced by indomethacin worsened (90
, p < 0.001). Total necrosis of small intestine as well as increased ulcer and perforation of gastric and duodenal ulcers induced by acetic acid and cysteamine were observed. There was also worsening of gastric necrotic area with stress (60-90
, p < 0.05). Celecoxib and rofecoxib showed neutrophilia (5,000/mm3) similar to that presented by indomethacin, but there was no leukocyte infiltration in the gastric mucosa; thus we can consider it a COX-2 selective NSAID (non-steroidal anti-inflammatory drug). CONCLUSION: Dose-dependent administration of celecoxib and rofecoxib as COX-2 inhibitors and non-COX-1 inhibitors, respectively, did not produce toxic injuries on healthy gastrointestinal mucosa, thus providing a broad therapeutic spectre. On the other hand, when administered in presence of altered gastrointestinal mucosa, they worsened and complicated gastric ulcers, and also induced necrosis in the small intestine, thereby restricting their clinical use.
RESUMEN
In 5 random groups of Wistar rats (n = 15 for each group), ulcerogenic doses of NSAIDs COX-1-COX-2 inhibitors such as indomethacin were compared with Celecoxib (COX-2 inhibitor); the production of antrum gastric ulcers and bowel and colon necrotic areas was studied. Celecoxib was given each 12 hs orally and subcutaneously during 5 days and gastrointestinal lesions were not found; in contrast, Celecoxib given after indomethacin aggravated antrum gastric ulcers (p < 0.001); intestinal massive necrosis and death were observed in all the rats. We conclude that Celecoxib does not induce gastrointestinal lesions in healthy mucosa; in contrast, Celecoxib amplifies the gastrointestinal lesions induced by indomethacin.
RESUMEN
En diferentes grupos de ratas Wistar (n=15), se estudiaron AINEs inhibidores selectivos de la COX-2, como delecoxib y refecoxib, en cinco modelos experimentales: 1) Celecoxib y rofecoxib por vía oral y dosis dependiente durante 5 días y 24 hs. Después de indometacina oral. 2) Similar a 1, pero subcutáneo. 3) Ulcera gástrica inducida por ácido acético glacial. 4) Ulcera duodenal por cisteamina. 5) Estrés por inmovilización e inmersión en agua a 15 grados Celsius durante 6 horas. Celecoxib y rofecoxib por vía oral o SC en mucosa gastrointestinal sana no provaron lesiones necróticas en una superficie del 0 grados Celsius, presentanto histología normal; en cambio, agravaron y complicaron lesiones inducidas en forma previa por indometacina en más del 90 por ciento (p<0,001), con necrosis masiva del intestino delgado, así como ampliaron y causaron perforaciones en las úlceras gástricas y duodenales inducidas por ácido acético y cisteamina. Se produjo asimismo agravación de la zona necrótica gástrica por estrés en un 60-90 por ciento (p<0,05). Celecoxib y rofecoxib condujeron a una neutrofilia de 5000/mm3, similar a la inducida por la indometacina; en cambio, no produjeron infiltración leucocitaria en mucosa gástrica (MPO), siendo un marcador de AINE selectivo COX-2. Se concluyó que celecoxib y rofecoxib, administrados en dosis dependiente como inhibidores de COX-2 y no COX-1, no provocaron en mucosa gastrointestinal sana ninguna lesión por toxicidad, observándose un amplio margen terapéutico. En cambio, suministrados en mucosa gastrointestinal dañada agravaron y complicaron las lesiones ulcerosas gástricas y necróticas intestinales, limitando su uso en clínica. (AU)