Son yıllarda angiotensin konverting enzim (ACE) inhibitörlerinin nitrik oksit (NO) ile ilişkili olarak aterosklerozdan koruyucu etkileri olduğu bildirilmiştir. Bu amaçla ülkemizde bulunan kaptopril (K), enalapril (E), silazapril (S)'in normotensif annelerin sağlıklı bebeklerinin umbilikal arter segmentleri kullanılarak NO ile ilişkisi araştırıldı. Önceden 10-1 M konsantrasyonda BaCl2 ile kasılan umbilikal arter şeritlerinin 10-8'den 10-4 M konsantrasyonlarda K, E ve S ile tek başına ve bir guanilat siklaz inhibitörü olan metilen mavisi (MV) eklenerek maksimum gevşeme cevapları ölçüldü. K ile maksimum gevşeme cevabı 10-7, 10-6, 10-5, 10-4 konsantrasyonlarında MV eklenerek elde edilenlerden anlamlı şekilde daha fazlaydı (p
Recently, it was reported that atherosclerosis is associated with vascular endothelial dysfunction and reduced nitric oxide (NO) activity. Enhancement of NO activity may have an antiatherogenic action. This study was performed to investigate the role of NO on the vasodilatory effect of captopril (K), enalapril (E), cilazapril (S) on isolated human umbilical artery strips. Umbilical artery strips were precontracted by 10-1 M BaCl2 and then angiotensin converting enzyme inhibitors (ACEIs) alone were added in 10-8 to 10-4 M concentrations, and relaxation responses for ACEIs were measured. The same investigations and measurements were repeated after incubation of artery strips with methylene blue (MV) for 30 minutes. Maximum relaxation responses with K were stronger at consentrations of 10-7, 10-6, 10-4 than those of incubated with MV (p<0.05). Maximum relaxation responses with E were stronger at consentrations of 10-6, 10-5, 10-4 than those of incubated with MV (p<0.05). Similarly, Maximum relaxation responses with S were stronger at consentrations of 10-5, 10-4 than those of incubated with MeB (p<0.05). K's mazimum relaxation responses were more stronger than those of other ACEIs (p<0.05). We think that the sulfhydryl-containing ACEIs, such as captopril, have stronger relaxation effect compared to other ones. To determine effects of ACEI on atherosclerosis development, comperative studies should be done.
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