Influência do octreotide subcutâneo na cicatrização de sutura gástrica em ratos Effect of octreotide administered subcutaneously on the healing of gastric sutures in rats

Abstract

RACIONAL: Octreotide, análogo sintético da somatostatina, é potente inibidor da secreção gástrica, intestinal e pancreática. Reduz fluxo sangüíneo esplâncnico, acelera esvaziamento gástrico e prolonga tempo de trânsito intestinal, estimulando a absorção de água e eletrólitos. Freqüentemente é utilizado no tratamento das fístulas digestivas pela sua capacidade de reduzir o débito da fístula, porém a redução do fluxo sangüíneo poderia interferir negativamente na cicatrização. OBJETIVO: Avaliar a influência do octreotide na cicatrização de sutura gástrica em ratos. MÉTODOS: Foram utilizados 39 ratos Wistar machos, divididos em dois grupos, controle e octreotide, subdivididos em 4 e 7 dias, de acordo com o dia da morte do animal. Todos foram submetidos à gastrotomia e fechamento com pontos seromusculares interrompidos. Os animais do grupo octreotide receberam dose única diária do medicamento por via subcutânea. O grupo controle recebeu solução salina a 0,9%. Foram determinados o percentual de colágeno maduro e imaturo, pela técnica de picrosirius-red F3BA. O cálculo do índice de maturação do colágeno e determinação da força de ruptura (FRT) e força máxima de tração (FMT), foi testada em tensiômetro computadorizado. Utilizou-se para análise estatística, os testes t de Student e Kruskal-Wallis com nível de significância de PBACKGROUND: Octreotide, a somatostatin synthetic analogue, is a potent inhibitor of gastric intestinal and pancreatic secretions. It also inhibits many trophic and anabolics hormones, decreases splanchnic blood flow, accelerates gastric emptying and prolongs intestinal transit time, increasing the absorption of water and electrolytes. AIM: Evaluate the effects of octreotide on gastric sutures in rats. METHODS: Thirty-nine male adult Wistar rats were used, divided into control group and octreotide group. They were further subdivided into two subgroups, according to the day they were killed, the 4th or the 7th postoperative day. All animals were submitted to gastric longitudinal incisions, were closed using seromuscular interrupted stitches. The animals from the octreotide group received subcutaneous injections of octreotide. Control group received 0,9% isotonic saline. The samples of the stomach were obtained in order to determine the percentage of mature collagen and immature collagen, by picrosirius-red F3BA technique, the collagen maturation index and to determine the breaking strength and maximum strength force, tested in a computerized tensiometer. For statistical analysis, Student's t and Kruskall-Wallis' tests were applied, with the level of significance set at P<0.05. RESULTS: There was no difference in the percentage of immature collagen beeween the groups. The deposition of mature colagen was higher in the control group on the 7th postoperative day (21,43±1,06 vs.11,26±1,44, P=0,0000); in the octreotide group there was no difference. Comparing control and octreotide groups the deposition of mature collagen is higher in the octreotide group on the 4th postoperative day (19,13±1,38 vs.11,26±1,44, P=0,001). The collagen maturation index was higher in the octreotide group on the 4th postoperative day (1,07±0,07 vs 0,65±0,05, P=0,0001). The maximum strength force and the breaking strength were similar between control and octreotide groups. CONCLUSIONS: Octreotide given subcutaneously in rats is associated with higher proportion of mature collagen and does not influence the maximum strength force and the breaking strength of gastric sutures in rats.

Keywords

• Octreotide
• Colágeno
• Sutura
• Octreotide
• Collagen