Gustavo Frindt, Ph.D.

Associate Professor of Research in Physiology and Biophysics


1300 York Avenue, Room LC-510
New York, NY 10065

Research Areas

Research Summary:

Our research aim is to define the transport processes of sodium and water and their control mechanisms in the renal collecting tubule. Two areas of investigation are being pursued. First, we have recently described in freshly dissected tubules the changes in activity of single sodium channels from the apical membrane of principal cells caused by variations in the intracellular sodium level. Channel activity is decreased when the rate of sodium entry into the cell temporarily exceeds that of sodium exit through the sodium pump, and increased when the rate of sodium entry is decreased. At the present we are studying whether calcium ion-dependent kinases are involved in the regulation of these sodium channels under conditions of changes in cell sodium. Second, we have cloned a protein located in the medullary collecting duct of the rat kidney that is a water channel when it is expressed in Xenopus laevis oocytes. This protein is a member of a family of membrane intrinsic proteins. Now we are studying the exact localization of the protein in the nephron cells and other organs, the selectivity of the channel for some small organic solutes, and whether the channel is regulated by the level of vasopressin and/or the water balance of the animal.

Recent Publications:

  1. Wang, T, Liu, T, Xu, S, Frindt, G, Weinstein, AM, Palmer, LG et al.. High dietary K+ intake inhibits proximal tubule transport. Am J Physiol Renal Physiol. 2023;325 (2):F224-F234. doi: 10.1152/ajprenal.00013.2023. PubMed PMID:37318989 PubMed Central PMC10396284.
  2. Frindt, G, Meyerson, JR, Satty, A, Scandura, JM, Palmer, LG. Expression of ENaC subunits in epithelia. J Gen Physiol. 2022;154 (10):. doi: 10.1085/jgp.202213124. PubMed PMID:35939271 PubMed Central PMC9387651.
  3. Yang, L, Xu, Y, Gravotta, D, Frindt, G, Weinstein, AM, Palmer, LG et al.. ENaC and ROMK channels in the connecting tubule regulate renal K+ secretion. J Gen Physiol. 2021;153 (8):. doi: 10.1085/jgp.202112902. PubMed PMID:34143184 PubMed Central PMC8217949.
  4. Frindt, G, Shi, S, Kleyman, TR, Palmer, LG. Cleavage state of γENaC in mouse and rat kidneys. Am J Physiol Renal Physiol. 2021;320 (3):F485-F491. doi: 10.1152/ajprenal.00536.2020. PubMed PMID:33522411 PubMed Central PMC7988816.
  5. Yang, L, Frindt, G, Xu, Y, Uchida, S, Palmer, LG. Aldosterone-dependent and -independent regulation of Na+ and K+ excretion and ENaC in mouse kidneys. Am J Physiol Renal Physiol. 2020;319 (2):F323-F334. doi: 10.1152/ajprenal.00204.2020. PubMed PMID:32628540 PubMed Central PMC7473898.
  6. Frindt, G, Bertog, M, Korbmacher, C, Palmer, LG. Ubiquitination of renal ENaC subunits in vivo. Am J Physiol Renal Physiol. 2020;318 (5):F1113-F1121. doi: 10.1152/ajprenal.00609.2019. PubMed PMID:32174140 PubMed Central PMC7294337.
  7. Frindt, G, Yang, L, Bamberg, K, Palmer, LG. Na restriction activates epithelial Na channels in rat kidney through two mechanisms and decreases distal Na+ delivery. J Physiol. 2018;596 (16):3585-3602. doi: 10.1113/JP275988. PubMed PMID:29737520 PubMed Central PMC6092292.
  8. Frindt, G, Yang, L, Uchida, S, Weinstein, AM, Palmer, LG. Responses of distal nephron Na+ transporters to acute volume depletion and hyperkalemia. Am J Physiol Renal Physiol. 2017;313 (1):F62-F73. doi: 10.1152/ajprenal.00668.2016. PubMed PMID:28356292 PubMed Central PMC5538837.
  9. Yang, L, Frindt, G, Lang, F, Kuhl, D, Vallon, V, Palmer, LG et al.. SGK1-dependent ENaC processing and trafficking in mice with high dietary K intake and elevated aldosterone. Am J Physiol Renal Physiol. 2017;312 (1):F65-F76. doi: 10.1152/ajprenal.00257.2016. PubMed PMID:27413200 PubMed Central PMC5283884.
  10. Frindt, G, Gravotta, D, Palmer, LG. Regulation of ENaC trafficking in rat kidney. J Gen Physiol. 2016;147 (3):217-27. doi: 10.1085/jgp.201511533. PubMed PMID:26880754 PubMed Central PMC4772376.
  11. Frindt, G, Palmer, LG. Acute effects of aldosterone on the epithelial Na channel in rat kidney. Am J Physiol Renal Physiol. 2015;308 (6):F572-8. doi: 10.1152/ajprenal.00585.2014. PubMed PMID:25520012 PubMed Central PMC4360037.
  12. Gleason, CE, Frindt, G, Cheng, CJ, Ng, M, Kidwai, A, Rashmi, P et al.. mTORC2 regulates renal tubule sodium uptake by promoting ENaC activity. J Clin Invest. 2015;125 (1):117-28. doi: 10.1172/JCI73935. PubMed PMID:25415435 PubMed Central PMC4382226.
  13. Carattino, MD, Mueller, GM, Palmer, LG, Frindt, G, Rued, AC, Hughey, RP et al.. Prostasin interacts with the epithelial Na+ channel and facilitates cleavage of the γ-subunit by a second protease. Am J Physiol Renal Physiol. 2014;307 (9):F1080-7. doi: 10.1152/ajprenal.00157.2014. PubMed PMID:25209858 PubMed Central PMC4216988.
  14. Frindt, G, Li, H, Sackin, H, Palmer, LG. Inhibition of ROMK channels by low extracellular K+ and oxidative stress. Am J Physiol Renal Physiol. 2013;305 (2):F208-15. doi: 10.1152/ajprenal.00185.2013. PubMed PMID:23678039 PubMed Central PMC3725663.
  15. Patel, AB, Frindt, G, Palmer, LG. Feedback inhibition of ENaC during acute sodium loading in vivo. Am J Physiol Renal Physiol. 2013;304 (2):F222-32. doi: 10.1152/ajprenal.00596.2012. PubMed PMID:23171553 PubMed Central PMC3543624.
  16. Frindt, G, Palmer, LG. Effects of insulin on Na and K transporters in the rat CCD. Am J Physiol Renal Physiol. 2012;302 (10):F1227-33. doi: 10.1152/ajprenal.00675.2011. PubMed PMID:22357918 PubMed Central PMC3362065.
  17. Palmer, LG, Patel, A, Frindt, G. Regulation and dysregulation of epithelial Na+ channels. Clin Exp Nephrol. 2012;16 (1):35-43. doi: 10.1007/s10157-011-0496-z. PubMed PMID:22038262 .
  18. Frindt, G, Palmer, LG. Regulation of epithelial Na+ channels by adrenal steroids: mineralocorticoid and glucocorticoid effects. Am J Physiol Renal Physiol. 2012;302 (1):F20-6. doi: 10.1152/ajprenal.00480.2011. PubMed PMID:22012806 PubMed Central PMC3251340.
  19. Frindt, G, Houde, V, Palmer, LG. Conservation of Na+ vs. K+ by the rat cortical collecting duct. Am J Physiol Renal Physiol. 2011;301 (1):F14-20. doi: 10.1152/ajprenal.00705.2010. PubMed PMID:21454253 PubMed Central PMC3129893.
  20. Yang, L, Frindt, G, Palmer, LG. Magnesium modulates ROMK channel-mediated potassium secretion. J Am Soc Nephrol. 2010;21 (12):2109-16. doi: 10.1681/ASN.2010060617. PubMed PMID:21030597 PubMed Central PMC3014024.
Search PubMed