BMAL1 in Renal Distal Segments Does Not Contribute to Variations in Beat-to-Beat Heart Rate but a Low Potassium Diet Increases Heart Rate Variability

Emilio Roig

Authors:  Emilio M. Roig, G. Ryan Crislip, I Jeanette Lynch, Charles S. Wingo, and Michelle L. Gumz

Faculty Mentor: Michelle L. Gumz

College:  College of Medicine


Heart rate variability (HRV) is an indicator of cardiovascular health. The circadian clock regulates a variety of physiological functions such as HR. The goal of this study was to determine 1) if knockout male mice (KO) lacking a core circadian transcription factor, BMAL1, within distal segments of the kidney affects HRV and 2) if dietary potassium depletion affects HRV. HR in male mice, measured via telemetry, was higher during the active period vs. inactive. Furthermore, KO exhibited a faster HR than control mice. HRV determined by Fourier analysis (Kubios software) demonstrated that there was greater variability during the inactive period vs. active in high frequency bands (PTIME<0.0001) but no genotype differences were found. Additionally, there were no differences in the ratio of low:high frequency regardless of active period or genotype (PTIME=0.4; PGENOTYPE=0.3). HRV was higher during the active period following 5 days of potassium depletion compared to baseline (PTREATMENT<0.01). BMAL1 in renal distal segments does not contribute to variations in beat-to-beat BP. KO exhibit a faster heart rate independent of variability. Potassium depletion increases HRV in this experimental setting. Using this analysis software, changes in BP variability reflected changes in heart rate with faster heart rates correlating with less variability.

Poster Pitch

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9 Responses
  1. Valerie Prytkova


    What a phenomenal person… What a phenomenal project!! You absolutely rock, and I hope life has been treating you well! 🙂

  2. Jonathan Smith

    Hi Emilio!

    You did an amazing job with your presentation and poster! I agree that the study should be repeated with a low potassium and high sodium diet. You may have mentioned this somewhere, but was sodium kept constant in this experiment? Thanks!


  3. Emilio

    Hi Jonathan,

    Yes, sodium was kept constant for this experiment at 0.2% Na. If this were to be repeated with a high Na diet, I believe we would do a 2% Na diet with 0% K.