催產素酶

催產素酶Oxytocinase)是一種可以代謝催產素[1]。最著名的催產素酶是Leucyl-cystinyl氨肽酶英語leucyl/cystinyl aminopeptidase[1][2],本身也是腦啡肽酶,已知也有其他的催產素酶[1][3]。懷孕時,催產素酶可以平衡催產素的濃度,因為隨著胎兒成長,胎兒分泌的催產素會增加,催產素酶會分解胎兒分泌的催產素,以維持平衡[2]。有研究發現催產素酶的濃度會隨胎齡漸漸增加,直到分娩為止,因此胎兒的發育可以用催產素酶濃度進行評估[4]

抑制劑

阿嗎他定英語Amastatin短整合蛋白英語lebestatin(ubenimex)及嘌呤黴素英語puromycin都可以抑制催產素的代謝,不過他們也會抑制其他多肽(像是後葉加壓素甲硫腦素英語met-enkephalin強啡肽英語dynorphin A等)的分解,[5][3][6]EDTA、L-甲硫氨酸鄰二氮菲磷酸阿米酮英語phosphoramidon也會抑制催產素的代謝[7]

相關條目

參考資料

  1. ^ 1.0 1.1 1.2 Tsujimoto M, Hattori A. The oxytocinase subfamily of M1 aminopeptidases. Biochim. Biophys. Acta. 2005, 1751 (1): 9–18. PMID 16054015. doi:10.1016/j.bbapap.2004.09.011. 
  2. ^ 2.0 2.1 Nomura S, Ito T, Yamamoto E, Sumigama S, Iwase A, Okada M, Shibata K, Ando H, Ino K, Kikkawa F, Mizutani S. Gene regulation and physiological function of placental leucine aminopeptidase/oxytocinase during pregnancy. Biochim. Biophys. Acta. 2005, 1751 (1): 19–25. PMID 15894523. doi:10.1016/j.bbapap.2005.04.006. 
  3. ^ 3.0 3.1 Mizutani S, Yokosawa H, Tomoda Y. Degradation of oxytocin by the human placenta: effect of selective inhibitors. Acta Endocrinol. 1992, 127 (1): 76–80. PMID 1355623. doi:10.1530/acta.0.1270076. 
  4. ^ Klimek, Marek. Comparative analysis of ACTH and oxytocinase plasma concentration during pregnancy. Neuro Endocrinology Letters. August 2005, 26 (4): 337–341. ISSN 0172-780X. PMID 16136013. 
  5. ^ Meisenberg G, Simmons WH. Amastatin potentiates the behavioral effects of vasopressin and oxytocin in mice. Peptides. 1984, 5 (3): 535–9. PMID 6540873. doi:10.1016/0196-9781(84)90083-4. 
  6. ^ Stancampiano R, Melis MR, Argiolas A. Proteolytic conversion of oxytocin by brain synaptic membranes: role of aminopeptidases and endopeptidases. Peptides. 1991, 12 (5): 1119–25. PMID 1800950. doi:10.1016/0196-9781(91)90068-z. 
  7. ^ Itoh C, Watanabe M, Nagamatsu A, Soeda S, Kawarabayashi T, Shimeno H. Two molecular species of oxytocinase (L-cystine aminopeptidase) in human placenta: purification and characterization. Biol. Pharm. Bull. 1997, 20 (1): 20–4. PMID 9013800. doi:10.1248/bpb.20.20.