Brief Article
Copyright ©2013 Baishideng. All rights reserved.
World J Nephrol. Feb 6, 2013; 2(1): 11-16
Published online Feb 6, 2013. doi: 10.5527/wjn.v2.i1.11
Pericytes synthesize renin
Alison C Berg, Catalina Chernavvsky-Sequeira, Jennifer Lindsey, R Ariel Gomez, Maria Luisa S Sequeira-Lopez
Alison C Berg, Catalina Chernavvsky-Sequeira, Jennifer Lindsey, R Ariel Gomez, Maria Luisa S Sequeira-Lopez, Department of Pediatrics, University of Virginia School of Medicine, Charlottesville, VA 22908, United States
Author contributions: Berg AC and Chernavvsky-Sequeira C contributed equally to this work; Lindsey J, Gomez RA and Sequeira-Lopez MLS designed the research; Berg AC, Chernavvsky-Sequeira C and Lindsey J performed the research; Berg AC, Chernavvsky-Sequeira C, Gomez RA and Sequeira-Lopez MLS analyzed the data; Berg AC and Chernavvsky-Sequeira C wrote the manuscript; Lindsey J reviewed the manuscript; Gomez RA and Sequeira-Lopez MLS corrected the manuscript.
Supported by National Institutes of Health Grants RO1 DK-091330 (to Sequeira-Lopez MLS) and R37 HL066242 and RO1 HL096735 and the Center of Excellence in Pediatric Nephrology P50 DK096373 (to Gomez RA)
Correspondence to: Maria Luisa S Sequeira-Lopez, MD, Department of Pediatrics, University of Virginia School of Medicine, 409 Lane Rd MR4 Bldg room 2001, Box 801334, Charlottesville, VA 22908, United States. msl7u@virginia.edu
Telephone: +1-434-9245065-1741 Fax: +1-434-9824328
Received: December 6, 2012
Revised: January 31, 2013
Accepted: February 5, 2013
Published online: February 6, 2013
Abstract

AIM: To investigate renin expression in pericytes during normal kidney development and after deletion of angiotensinogen, the precursor for all angiotensins.

METHODS: We examined the distribution of renin expressing cells by immunoshistochemistry in the interstitial compartment of wild type (WT) and angiotensinogen deficient (AGT -/-) mice at different developmental stages from embryonic day 18 (E18: WT, n = 4; AGT -/-, n = 5) and at day 1 (P1: WT, n = 5; AGT -/-, n = 5), 5 (P5: WT, n = 7; AGT -/-, n = 8), 10 (P10: WT, n = 3; AGT -/-, n = 5), 21 (P21: WT, n = 7; AGT -/-, n = 5), 45 (P45: WT, n = 3; AGT -/-, n = 3), and 70 (P70: WT, n = 2; AGT -/-, n = 2) of postnatal life. We quantified the number of pericytes positive for renin at all the developmental stages mentioned above and compared the results of AGT -/- mice to their WT counterparts.

RESULTS: In WT mice, renal interstitial pericytes synthesize renin in early life supporting a lineage relationship with renin cells in the vasculature. The number of pericytes positive for renin per area of 0.32 mm2 (density) in WT mice was maintained from fetal life till weaning age (E18 = 4.25 ± 0.63, P1 = 3.75 ± 0.48, P5 = 3.75 ± 0.48, P10 = 4 ± 0.71, P21 = 3.8 ± 0.58) and markedly decreased in adult life (P45 = 1.2 ± 0.37, P70 = 0.8 ± 0.20). On the other hand, in AGT -/- mice the density of pericytes expressing renin was not significantly different from WT mice at E18 and P1: E18 = 5.75 ± 0.50 vs 4.25 ± 0.63 (P = 0.106), P1 = 9.25 ± 3.50 vs 3.75 ± 0.48 (P = 0.175) but significantly increased from P5 till P70: P5 = 38.25 ± 5 vs 3.75 ± 0.48 (P = 0.0004), P10 = 173 ± 7.50 vs 4 ± 0.70 (P = 5.24567 × 10-7), P21 = 83 ± 6.70 vs 3.8 ± 0.58 (P = 2.97358 × 10-6), P45 = 49 ± 3.50 vs 1.2 ± 0.37 (P = 8.18274 x 10-7) and P70 = 17.8 ± 2.30 vs 0.8 ± 0.20 (P = 3.51151 × 10-5). The AGT -/- mice showed a marked increase in the number of pericytes per field studied starting from P5, reaching its peak at P10, and then a gradually decreasing until P70.

CONCLUSION: Interstitial pericytes synthesize renin during development and the number of renin-expressing pericytes increases in response to a homeostatic threat imposed early in life such as lack of angiotensinogen.

Keywords: Interstitium, Homeostasis, Angiotensinogen, Kidney, Renin angiotensin system, Development, Angiotensin deficiency, Gene deletion