Gülnar VATANDAŞ GÜLAÇTI, Cemil AKGÜL, Pervin VURAL, At ALL.

MENOPOZUN VE HORMON REPLASMAN TEDAVİSİNİN PLAZMA NİTRAT/NİTRİT VE ENDOTELİN-1 DÜZEYLERİNE ETKİSİ

Amaç: Bu çalışmanın amacı menopoz sonrası (postmenopozda) plazma nitrat/nitrit (NOx) ve endotelin-1 (ET-1) düzeylerinde meydana gelen değişiklikleri, ve farklı hormon replasman tedavilerinin (HRT) bu vazoaktif maddeler üzerindeki etkisini incelemekti. Gereç ve yöntem: Çalışmaya 50 sağlıklı postmenopozal (PMW) ve 25 sağlıklı premenopozal kadın dahil edildi. Postmenopozal kadınlar rastgele iki alt gruba ayrıldı: siklik HRT ve kesintisiz HRT alan alt gruplar. 1. grup (siklik HRT) 2 ay boyunca siklüsün 1-28 günleri arasında 0,625mg konjuge estojen (CEE) + 18-28 günleri arasında 5mg medroksiprogesteron asetat (MPA) alan kadınlardan oluşturuldu. 2. grup (kesintisiz HRT) ise 2 ay boyunca siklüsün 1-28 günleri arasında 0,625mg CEE + 2,5mg MPA alan kadınlardan oluşturuldu. Sonuçların istatiksel değerlendirilmesinde Kruskal-Wallis, Mann-Whitney U, Wilcoxon signed ranks, ve Spearman korelasyon testleri kullanıldı. Bulgular: Premenopozal olanlara kıyasla postmenopozal kadınlarda NOx konsantrasyonları azalırken, ET-1 konsantrasyonları artmaktadır. Premenopozal kadınlarda NOx ve ET-1 arasında görülen pozitif korelasyon, bu iki parametre arasında bir denge olduğunu göstermektedir. Bu denge menopozda değişmektedir. İki aylık HRT menopozla azalan NOx’nın artmasına neden olurken, ET-1 üzerine bir etkisi yoktur, böylece HRT NOx ve ET-1 arasındaki dengeyi düzenlemektedir. Siklik HRT’ye kıyasla kesintisiz HRT endotel fonksiyonu ve NOx/ET-1 arasındaki kritik dengenin sürdürülmesinde daha başarılı olduğunu söyleyebiliriz. Sonuç: Sonuçlarımızdan da görüldüğü gibi, HRT’ye cavaben postmenopozal kadınların bir kısmında (3/4) plazma NOx düzeyleri artmakta, bir kısmında ise (1/4) azalmaktadır; bu da, hepsi olmasa da postmenopozal kadınların çoğunun HRT'nin pozitif etkilerinden yararlandığını söyleyebiliriz.

Anahtar Kelimeler:

Nitrik oksit, endotelin-1, hormon replasman tedavisi (HRT), estrojen, progestin, menopoz

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