Perfusion of the renal medulla plays an important role in salt and water balance. Pericytes are smooth muscle-like cells that impart contractile function to descending vasa recta (DVR), the arteriolar segments that supply the medulla with blood flow. DVR contraction by ANG II is mediated by depolarization resulting from an increase in plasma membrane Cl(-) conductance that secondarily gates vol...

The discovery of aquaporin-1 (AQP1) by Agre and associates answered the longstanding biophysical question of how water specifically crosses biological membranes. In the kidney at least 7 aquaporins are expressed at distinct sites. AQP1 is extremely abundant in the proximal tubule and descending thin limb and is essential for urinary concentration. AQP2 is exclusively expressed in the principal ...

Elżbieta Kompanowska-Jezierska, Helle Wolff, Marta Kuczeriszka, Jan B. Gramsbergen, Agnieszka Walkowska, Edward J. Johns, and Peter Bie Department of Physiology and Pharmacology, University of Southern Denmark, Odense, Denmark; Laboratory of Renal and Body Fluid Physiology, M. Mossakowski Medical Research Centre of the Polish Academy of Sciences, Warsaw, Poland; Department of Anatomy and Neurob...

All the world's religions recommend a period of fasting, and of these, one whole month of intermittent fasting every year is particular to Islam. Muslims have two meals, one immediately after sunset and the other just before dawn with a period of fasting ranging from 11-18 hours. Therefore, we can assume that physiological changes occurring during Ramadan would be different from those occurring...

Michel Baum, Katherine Twombley, Jyothsna Gattineni, Catherine Joseph, Lin Wang, Qiuyu Zhang, Vangipuram Dwarakanath, and Orson W. Moe Department of Pediatrics, University of Texas Southwestern Medical Center at Dallas; Dallas, Texas; Department of Internal Medicine, University of Texas Southwestern Medical Center at Dallas; Dallas, Texas; Department of Physiology, University of Texas Southwest...

Renal proximal tubules secrete various organic anions, including drugs and p-aminohippurate (PAH). Uptake of PAH from blood into tubule cells occurs by exchange with intracellular alpha-ketoglutarate and is mediated by the organic anion transporter 1. PAH exit into tubule lumen is species specific and may involve ATP-independent and -dependent transporters.

FIRST OF ALL, I WOULD LIKE TO THANK Tom Kleyman for his service as Editor-in-Chief of AJP-Renal Physiology for the last six years. Tom has shown exemplary leadership during his tenure, and the journal has grown and increased in recognition as one of the leaders in publishing outstanding renal research. Also, I would like to thank my fellow Associate Editors, Gerry Apodaca, Jeff Garvin, Lisa Sta...