Histochemical and Immunocytochemical Investigations of the Fetal Extravascular and Vascular Contractile System in the Normal Placenta and During Preeclampsia
In the normal human placenta, angiotensin II is generated in the fetoplacental vascular bed and is thought to be important in the local modulation of vascular resistance (Maguire et al. 1988). The angiotensin II-degrading peptidase aminopeptidase A (L-α-aspartyl (L-α-glutamyl)-peptide hydrolase, EC 18.104.22.168, formerly angiotensinase A, now glutamyl aminopeptidase, EAP) has been separated biochemically and its angiotensinase activity confirmed (Mizutani et al. 1981). Therefore, it may be assumed that in analogy to the kidney renin-angiotensin system, placental angiotensin may also be cleaved by EAP. Histochemically, low activities of this enzyme have been demonstrated in the media of fetal placental blood vessels (Gossrau et al. 1987).
KeywordsHydrolysis EDTA Neral Catalysis CaCl2
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