Zenobiyotiklerin Metabolizması

Organizmaların karşılaştığı yabancı kimyasal maddeler veya ilaçlar zenobiyotikler olarak adlandırılır. Zenobiyotikler, vücut için toksik maddeler olup, vücuda alındıktan sonra etki yerlerine dağılırlar ve çeşitli yollarla elimine edilmeye çalışılırlar. Bunların metabolize edildiği ana organ karaciğerdir. Yaklaşık 30 farklı enzim zenobiyotik metabolizmasına katılan tepkimeleri kataliz eder. Metabolizasyon işlemi iki aşamada gerçekleşir. Birinci aşamanın ana tepkimesi sitokrom P450 olarak bilinen bir grup monooksigenaz tarafından kataliz edilen hidroksillenmedir. İkinci aşamada hidroksilenmiş ürünler glukuronik asit, sülfat veya glutatyon gibi bir grup hidrofilik bileşikle konjuge edilir. Böylece lipofilik maddeler vücuttan atılabilecek suda çözünür bileşikler haline çevrilir. Zenobiyotik metabolizmasının daha iyi anlaşılması, zenobiyotiklerin zararlı etkilerinden korunmak için yapılacak olan çalışmalara zemin oluşturacaktır

Anahtar Kelimeler:

Zenobiyotik, Biyotransformasyon, Sitokrom P450

Zenobiyotiklerin Metabolizması

Keywords:

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