Go to JCI Insight
  • About
  • Editors
  • Consulting Editors
  • For authors
  • Publication ethics
  • Publication alerts by email
  • Advertising
  • Job board
  • Contact
  • Clinical Research and Public Health
  • Current issue
  • Past issues
  • By specialty
    • COVID-19
    • Cardiology
    • Gastroenterology
    • Immunology
    • Metabolism
    • Nephrology
    • Neuroscience
    • Oncology
    • Pulmonology
    • Vascular biology
    • All ...
  • Videos
    • Conversations with Giants in Medicine
    • Video Abstracts
  • Reviews
    • View all reviews ...
    • Clinical innovation and scientific progress in GLP-1 medicine (Nov 2025)
    • Pancreatic Cancer (Jul 2025)
    • Complement Biology and Therapeutics (May 2025)
    • Evolving insights into MASLD and MASH pathogenesis and treatment (Apr 2025)
    • Microbiome in Health and Disease (Feb 2025)
    • Substance Use Disorders (Oct 2024)
    • Clonal Hematopoiesis (Oct 2024)
    • View all review series ...
  • Viewpoint
  • Collections
    • In-Press Preview
    • Clinical Research and Public Health
    • Research Letters
    • Letters to the Editor
    • Editorials
    • Commentaries
    • Editor's notes
    • Reviews
    • Viewpoints
    • 100th anniversary
    • Top read articles

  • Current issue
  • Past issues
  • Specialties
  • Reviews
  • Review series
  • Conversations with Giants in Medicine
  • Video Abstracts
  • In-Press Preview
  • Clinical Research and Public Health
  • Research Letters
  • Letters to the Editor
  • Editorials
  • Commentaries
  • Editor's notes
  • Reviews
  • Viewpoints
  • 100th anniversary
  • Top read articles
  • About
  • Editors
  • Consulting Editors
  • For authors
  • Publication ethics
  • Publication alerts by email
  • Advertising
  • Job board
  • Contact
In hypertension, the kidney is not always the heart of the matter
Michael E. Mendelsohn
Michael E. Mendelsohn
View: Text | PDF
Commentary

In hypertension, the kidney is not always the heart of the matter

  • Text
  • PDF
Abstract

Blood pressure abnormalities are thought to originate from intrinsic changes in the kidney, a concept that has been largely unchallenged for more than 4 decades. However, recent molecular, cellular, and transgenic mouse studies support an alternative hypothesis: primary abnormalities in vascular cell function can also directly cause abnormalities of blood pressure. In this issue of the JCI, Crowley and coworkers describe the application of an elegant cross-renal transplant model to type 1A angiotensin (AT1A) receptor–deficient mice and their wild-type littermates to explore the relative contributions of renal and extrarenal tissues to the low blood pressure seen in the AT1A receptor–deficient animals. Their studies further support the emerging paradigm that primary abnormalities of the vasculature can make unique, nonredundant contributions to blood pressure regulation; the findings have potentially important implications for the ways we diagnose and treat blood pressure diseases in humans.

Authors

Michael E. Mendelsohn

×

Figure 2

Options: View larger image (or click on image) Download as PowerPoint
Vascular tone is dynamically regulated by MLC phosphorylation and dephos...
Vascular tone is dynamically regulated by MLC phosphorylation and dephosphorylation in VSMCs. Increases in VSMC intracellular calcium level via receptor-activated (pharmacomechanical) or ion channel–activated (electromechanical) pathways lead to MLCK activation. MLCK phosphorylates MLCs (MLC-P), activating the myosin ATPase, actinomyosin cross-bridging, and an increase in tension. PP1M dephosphorylates MLC-P, decreasing cell tension. PP1M is activated by the NO and nitrovasodilator effector PKGI, which has 2 isoforms (PKGIα and PKGIβ). RGS2, which is essential for normal blood pressure, causes VSMC relaxation by attenuating Gq protein–coupled receptor activation and associated rises in intracellular calcium concentration; it too is activated by PKGIα. PP1M is inhibited by Rho/Rho kinase (ROCK). The calcium-activated potassium channel, BKCa2+, is activated by PKG and by local calcium sparks, hyperpolarizing the cell, decreasing calcium entry, and decreasing MLCK activity. This shifts the equilibrium between MLC and MLC-P, causing relaxation. Blue, relaxant pathway; red, contractile pathway. GPCR, G protein–coupled receptor; IP3R, IP3 receptor; SR, sarcoplasmic reticulum; PLC, phospholipase C; CaM, calmodulin; IRAG, IP3R-associated cGMP kinase substrate.

Copyright © 2026 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)

Sign up for email alerts