New aspects of the renin-angiotensin system in blood pressure regulation

Institute of Applied Biochemistry, University of Tsukuba, Tsukuba, Ibaraki 305, Japan.
Trends in Endocrinology and Metabolism (Impact Factor: 9.39). 11/1995; 6(8):279-84. DOI: 10.1016/1043-2760(95)00156-5
Source: PubMed


The renin-angiotensin system, composed of enzymatic and signal-transduction cascades, plays a key role in the regulation of arterial blood pressure and in the development of certain forms of experimental and human hypertension. The products of this system, angiotensin peptides, exert a wide range of physiologically important effects on many tissues, including those of the cardiovascular system, through their actions on angiotensin receptors. Molecular genetic and transgenic studies have begun to implicate some of the genes encoding components of the renin-angiotensin system in the development of cardiovascular diseases. Recently, we succeeded in generating mice homozygous for a targeted disruption of the angiotensinogen gene (the only known precursor of angiotensins), resulting in the complete loss of angiotensin signals in vivo. Here, we review new developments related to the functional analysis of the renin-angiotensin system, in particular, by focusing on transgenic approaches including gene targeting.

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    • "Coupled with the presence of chymosin (Foltmann 1992) and pepsins (Ryle & Porter 1959) in the stomach to aid digestion and the presence of cathepsin D in the lysosome to aid protein degradation (Erickson & Blobel 1979), it was generally believed that aspartic proteases fell within a group classified as 'non-specific' degradation enzymes. However, this is not the case for all aspartic proteases, as evident from the specific processing roles that aspartic proteases play; for example, memapsin 2 (BACE; Vassar et al. 1999, Lin et al. 2000) and g-secretase (Wolfe et al. 1999) in the pathogenesis of Alzheimer's disease, or from the role of renin in the generation of angiotensin I (Fukamizu & Murakami 1995) and its function in the regulation of blood pressure. The yapsins (Cawley & Loh 2011) may also represent an exception to this classification. "
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