Rat modelinde sevofluran ve izofluran'ın akciğer dokusu üzerine etkilerinin biyokimyasal ve histopatolojik olarak incelenmesi
Investigation of biochemical and histopathological effects of Sevoflurane and Isoflurane on lung in rat model
Yazar: FATMA ACIL
Danışman: DOÇ. DR. UĞUR KOCA
Dokuz Eylül Üniversitesi / Tıp Fakültesi / Anesteziyoloji ve Reanimasyon Ana Bilim Dalı
Derece: Tıpta Uzmanlık, 2008
Konu: Anestezi ve Reanimasyon = Anesthesiology and Reanimation

Özet:
Amaç: Son yıllarda inhalasyon anesteziklerinin genel anestezi sırasında yaşanan pulmoner komplikasyonlardan sorumlu olabileceği savı gündeme gelmiştir. Bu ajanlara bağlı akciğer hasarının mekanizmasında aktive nötrofillerin yol açtığı endoteliyal hücre zedelenmesinin, üretilen serbest oksijen radikallerinin ve/veya proteazların rol aldığı düşünülmektedir. Bu deneysel çalışmada, sevofluran ve izofluranın akciğer dokusu üzerine etkilerinin rat modelinde incelenmesi amaçlanmıştır.Yöntem: Deney Hayvanları Etik Kurulu onamı alındıktan sonra 21 adet erişkin erkek Wistar Albino rat rastgele üç gruba ayrıldı, Kontrol Grubu (n=6); %50 oksijen + %50 hava; İzofluran Grubu (n=7) % 1.2 İzofluran (1 MAK) + %50 oksijen + %50 hava, Sevofluran Grubu (n=6) % 2.4 Sevofluran (1 MAK) + %50 oksijen + %50 hava ile 2 saat boyunca mekanik ventilatör ile solutuldu. Çalışma bitiminde ratlar mediyan sternotomi sonrası akciğerleri çıkartılarak sakrifiye edildi. Sol akciğer miyeloperoksidaz (MPO) aktivitesi ve thiobarbituric acid reactive substance (TBARS) düzeyinin incelenmesi ve sağ akciğer histopatolojik incelemeler için kullanıldı. Histopatolojik değerlendirmede hematoksilen-eosin ile ışık mikroskobu istatistiksel analizinde, alveoler makrofaj sayısı ve M-30 immun histokimya ile apoptozis değerlendirildi. Veriler Kruskal Wallis ve Mann ? Whitney U testleri kullanıldı. p < 0.05 anlamlı olarak kabul edildi.Bulgular: Gruplar arasında hemodinamik veriler ve kan gazları parametreleri açısından fark saptanmadı. Sevofluran Grubu'nda, Kontrol ve İzofluran Grubu'na göre MPO aktivitesi (sırasıyla; p:0.041, p:0.001) ve TBARS düzeyi (sırasıyla; p:0.041, p:0.035) anlamlı derecede düşük saptandı.İzofluran Grubu'nda, Kontrol ve Sevofluran Grubu'na göre alveoler makrofaj sayısı (sırasıyla; p:0.001, p:0.001) ve M-30 pozitif hücre sayısı (sırasıyla; p:0.001, p:0.001) anlamlı yüksek, Sevofluran Grubu'nda ise Kontrol Grubu'na göre anlamlı yüksek olarak saptandı (sırasıyla; p:0.002, p:0.002). Işık mikroskobik incelemede Sevofluran grubu ve daha fazla olmak üzere İzofluran Grubu'nda yaygın mononükleer hücre infiltrasyonu, diffüz alveoler hasar, alveoler ödem, alveoler septumlarda kalınlaşma, alveol lümeninde yoğun alveoler makrofaj ve daha az miktarda nötrofil ve tip II pnömositler gözlendi. Parankimde ise yaygın hemoraji, mononükleer hücre infiltrasyonu, ödem ve vasküler konjesyon saptandı.Sonuç: Bu çalışmanın sonuçlarına göre sevofluranın, izoflurana göre daha az pulmoner makrofaj aktivasyonu ve apoptozise neden olduğu saptanmıştır. Sevofluran Grubu'nda Kontrol Grubu'na göre daha düşük pulmoner MPO aktivitesi ve TBARS düzeyinin bulunması, sevofluranın antiinflamatuvar etkinlik gösterdiği şeklinde yorumlanabilir. Bununla birlikte hasarlı akciğer dokusu ile gerçekleştirilecek çalışmalara gereksinim vardır.Anahtar Kelimeler: izofluran, sevofluran, akciğer hasarı, apoptozis, inhalasyon ajanı, genel anestezi

Abstract:
Objective:In recent years, the thesis on inhalational anesthetics can be the reason for pulmonary complications during general anesthesia has come into a question. The probable mechanism of lung injury due to these agents has been considered as; endothelial cell injury caused by activated neutrophils, formation of reactive oxygen radicals and/or proteases. In this trial, it has been aimed to investigate the effects of sevoflurane and isoflurane on lung tissue in rat model.Method:After the approval of ethics committee for Research Animals, 21 adult male Wistar Albino rats were randomly allocated into three groups. The subjects were mechanically ventilated for 2 hours in Control group (n=7) with 50 % oxygen + 50 % air mixture; in Isoflurane group (n=7) with % 1.2 ( 1 MAC) isoflurane + 50 % oxygen + 50 % air and in Sevoflurane Group (n=7) with %2.4 ( 1 MAC) sevoflurane + 50 % oxygen + 50 % air mixture. At the end of the study, a median sternotomy was performed, lungs were removed and rats were sacrified. Left lung was used for pulmonary tissue myeloperoxidase activity and thiobarbituric acid reactive substances (MPO and TBARS ) determinations, right lung was used for histopathological determinations. Histopathological determinations were included, light microscope image analysis, alveolar macrophage count and M-30 immune histochemical analysis of apoptosis. Data were analyzed using Kruskal Wallis and Mann - Whitney U tests and p< 0.05 were regarded as statistically significant.Results: There were no statistical significance between groups when hemodynamic (heart rate, systolic blood pressures- diastolic blood pressures) and blood gases parameters (pH, PaO2, PaCO2) were compared. MPO activity in Sevoflurane group compared to isoflurane and control groups (p:0.001, p:0.041, respectively.) were significantly low. Furthermore, TBARS levels in Sevoflurane group compared to the other groups (p:0.035, p:0.041, respectively) were also significantly low. MPO activity in Isoflurane group were significantly high compared to control group.Alveolar macrophage counts (p:0.001, p:0.001, respectively) and M-30 positive cell counts (p:0.001, p:0.001, respectively) in Isoflurane group were significantly high compared to sevoflurane and control groups. On the other hand, the alveolar macrophage counts (p:0.002) and M-30 positive cell counts (p:0.002) in sevoflurane group were significantly high compared to control group. Light microscopic findings observed in sevoflurane group and any more in isoflurane group were; diffuse mononuclear cell infiltration, diffuse alveolar injury, alveolary oedema, thickening of alveolar septums, dense alveolar macrophage and light neutrophil and type II pneumocytes infiltration in alveol lumen. Furthermore, the paranchimal changes were diffuse hemorrhage, mononuclear cell infiltration, oedema and vascular congestion.Conclusion:This study is concluded as, sevoflurane produces pulmonary macrophage activation and apoptosis less than isoflurane does and since sevoflurane group has lower pulmonary tissue MPO activity and TBARS levels than control group, it can be pronounced that sevoflurane has an anti-inflammatory activity. Nevertheless, more studies should be made on injured lung tissue.Keywords: isoflurane, sevoflurane, lung injury, apoptosis, inhalational agent, general anesthesiaObjective:In recent years, the thesis on inhalational anesthetics can be the reason for pulmonary complications during general anesthesia has come into a question. The probable mechanism of lung injury due to these agents has been considered as; endothelial cell injury caused by activated neutrophils, formation of reactive oxygen radicals and/or proteases. In this trial, it has been aimed to investigate the effects of sevoflurane and isoflurane on lung tissue in rat model.Method:After the approval of ethics committee for Research Animals, 21 adult male Wistar Albino rats were randomly allocated into three groups. The subjects were mechanically ventilated for 2 hours in Control group (n=7) with 50 % oxygen + 50 % air mixture; in Isoflurane group (n=7) with % 1.2 ( 1 MAC) isoflurane + 50 % oxygen + 50 % air and in Sevoflurane Group (n=7) with %2.4 ( 1 MAC) sevoflurane + 50 % oxygen + 50 % air mixture. At the end of the study, a median sternotomy was performed, lungs were removed and rats were sacrified. Left lung was used for pulmonary tissue myeloperoxidase activity and thiobarbituric acid reactive substances (MPO and TBARS ) determinations, right lung was used for histopathological determinations. Histopathological determinations were included, light microscope image analysis, alveolar macrophage count and M-30 immune histochemical analysis of apoptosis. Data were analyzed using Kruskal Wallis and Mann - Whitney U tests and p< 0.05 were regarded as statistically significant.Results: There were no statistical significance between groups when hemodynamic (heart rate, systolic blood pressures- diastolic blood pressures) and blood gases parameters (pH, PaO2, PaCO2) were compared. MPO activity in Sevoflurane group compared to isoflurane and control groups (p:0.001, p:0.041, respectively.) were significantly low. Furthermore, TBARS levels in Sevoflurane group compared to the other groups (p:0.035, p:0.041, respectively) were also significantly low. MPO activity in Isoflurane group were significantly high compared to control group.Alveolar macrophage counts (p:0.001, p:0.001, respectively) and M-30 positive cell counts (p:0.001, p:0.001, respectively) in Isoflurane group were significantly high compared to sevoflurane and control groups. On the other hand, the alveolar macrophage counts (p:0.002) and M-30 positive cell counts (p:0.002) in sevoflurane group were significantly high compared to control group. Light microscopic findings observed in sevoflurane group and any more in isoflurane group were; diffuse mononuclear cell infiltration, diffuse alveolar injury, alveolary oedema, thickening of alveolar septums, dense alveolar macrophage and light neutrophil and type II pneumocytes infiltration in alveol lumen. Furthermore, the paranchimal changes were diffuse hemorrhage, mononuclear cell infiltration, oedema and vascular congestion.Conclusion:This study is concluded as, sevoflurane produces pulmonary macrophage activation and apoptosis less than isoflurane does and since sevoflurane group has lower pulmonary tissue MPO activity and TBARS levels than control group, it can be pronounced that sevoflurane has an anti-inflammatory activity. Nevertheless, more studies should be made on injured lung tissue.Keywords: isoflurane, sevoflurane, lung injury, apoptosis, inhalational agent, general anesthesiaObjective:In recent years, the thesis on inhalational anesthetics can be the reason for pulmonary complications during general anesthesia has come into a question. The probable mechanism of lung injury due to these agents has been considered as; endothelial cell injury caused by activated neutrophils, formation of reactive oxygen radicals and/or proteases. In this trial, it has been aimed to investigate the effects of sevoflurane and isoflurane on lung tissue in rat model.Method:After the approval of ethics committee for Research Animals, 21 adult male Wistar Albino rats were randomly allocated into three groups. The subjects were mechanically ventilated for 2 hours in Control group (n=7) with 50 % oxygen + 50 % air mixture; in Isoflurane group (n=7) with % 1.2 ( 1 MAC) isoflurane + 50 % oxygen + 50 % air and in Sevoflurane Group (n=7) with %2.4 ( 1 MAC) sevoflurane + 50 % oxygen + 50 % air mixture. At the end of the study, a median sternotomy was performed, lungs were removed and rats were sacrified. Left lung was used for pulmonary tissue myeloperoxidase activity and thiobarbituric acid reactive substances (MPO and TBARS ) determinations, right lung was used for histopathological determinations. Histopathological determinations were included, light microscope image analysis, alveolar macrophage count and M-30 immune histochemical analysis of apoptosis. Data were analyzed using Kruskal Wallis and Mann - Whitney U tests and p< 0.05 were regarded as statistically significant.Results: There were no statistical significance between groups when hemodynamic (heart rate, systolic blood pressures- diastolic blood pressures) and blood gases parameters (pH, PaO2, PaCO2) were compared. MPO activity in Sevoflurane group compared to isoflurane and control groups (p:0.001, p:0.041, respectively.) were significantly low. Furthermore, TBARS levels in Sevoflurane group compared to the other groups (p:0.035, p:0.041, respectively) were also significantly low. MPO activity in Isoflurane group were significantly high compared to control group.Alveolar macrophage counts (p:0.001, p:0.001, respectively) and M-30 positive cell counts (p:0.001, p:0.001, respectively) in Isoflurane group were significantly high compared to sevoflurane and control groups. On the other hand, the alveolar macrophage counts (p:0.002) and M-30 positive cell counts (p:0.002) in sevoflurane group were significantly high compared to control group. Light microscopic findings observed in sevoflurane group and any more in isoflurane group were; diffuse mononuclear cell infiltration, diffuse alveolar injury, alveolary oedema, thickening of alveolar septums, dense alveolar macrophage and light neutrophil and type II pneumocytes infiltration in alveol lumen. Furthermore, the paranchimal changes were diffuse hemorrhage, mononuclear cell infiltration, oedema and vascular congestion.Conclusion:This study is concluded as, sevoflurane produces pulmonary macrophage activation and apoptosis less than isoflurane does and since sevoflurane group has lower pulmonary tissue MPO activity and TBARS levels than control group, it can be pronounced that sevoflurane has an anti-inflammatory activity. Nevertheless, more studies should be made on injured lung tissue.Keywords: isoflurane, sevoflurane, lung injury, apoptosis, inhalational agent, general anesthesia