Transgenic mice expressing an intracellular fluorescent fusion of angiotensin II demonstrate renal thrombotic microangiopathy and elevated blood pressure. Am J Physiol Heart Circ Physiol 2010 Jun;298(6):H1807-18
Date
04/07/2010Pubmed ID
20363893Pubmed Central ID
PMC2886647DOI
10.1152/ajpheart.00027.2010Scopus ID
2-s2.0-77952623456 (requires institutional sign-in at Scopus site) 39 CitationsAbstract
We have generated transgenic mice that express angiotensin II (ANG II) fused downstream of enhanced cyan fluorescent protein, expression of which is regulated by the mouse metallothionein promoter. The fusion protein, which lacks a secretory signal, is retained intracellularly. In the present study, RT-PCR, immunoblot analyses, whole-animal fluorescent imaging, and fluorescent microscopy of murine embryonic fibroblasts confirm expression of the fusion protein in vivo and in vitro. The transgene is expressed in all tissues tested (including brain, heart, kidney, liver, lung, and testes), and radioimmunoassay of plasma samples obtained from transgenic mice indicate no increase in circulating ANG II over wild-type levels, consistent with intracellular retention of the transgene product. Kidneys from transgenic and corresponding wild-type littermates were histologically evaluated, and abnormalities in transgenic mice consistent with thrombotic microangiopathy were observed; microthrombosis was frequently observed within the glomerular capillaries and small vessels. In addition, systolic and diastolic blood pressures, measured by telemetry (n = 8 for each group), were significantly higher in transgenic mice compared with wild-type littermates. Blood pressure of line A male transgenic mice was 125 + or - 1.7 over 97 + or - 1.6 compared with 109 + or - 1.7 over 83 + or - 1.4 mmHg in wild-type littermates (systolic over diastolic). In summary, overexpression of an intracellular fluorescent fusion protein of ANG II correlates with elevated blood pressure and kidney pathology. This transgenic model may be useful to further explore the intracellular renin-angiotensin system and its implication in abnormal kidney function and hypertension.
Author List
Redding KM, Chen BL, Singh A, Re RN, Navar LG, Seth DM, Sigmund CD, Tang WW, Cook JLAuthor
Curt Sigmund PhD Chair, Professor in the Physiology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Angiotensin IIAnimals
Blood Pressure
Cells, Cultured
Disease Models, Animal
Female
Fibroblasts
Green Fluorescent Proteins
Hypertension
Kidney
Male
Mice
Mice, Inbred C57BL
Mice, Transgenic
RNA, Messenger
Thrombotic Microangiopathies