The Effect of Dietary Protein Source on Renal Hemodynamics in Conscious Rats
Abstract
Renal blood flow (RBF) autoregulation is an intrinsic mechanism that stabilizes RBF and glomerular filtration rate during changes in arterial blood pressure (BP), thereby protecting glomerular capillaries from barotrauma-mediated injury. Dietary protein source (e.g., plant- vs. animal-based protein) has been implicated in kidney disease susceptibility and progression, but its effects on RBF autoregulation remain unknown. This study examined whether plant-based (i.e., wheat-gluten) versus animal-based (i.e., casein) dietary protein affects mean arterial pressure (MAP), renal blood flow, and renal autoregulation in rats. We hypothesized that a diet with casein-based protein source will impair RBF autoregulatory responses to spontaneous blood pressure (BP) fluctuations in conscious rats. Male Sprague-Dawley rats (n=11) were instrumented with BP radiotelemetry transmitters and perivascular flow probes to measure BP and RBF in the conscious state. After recovery, rats received either a plant-based diet (Harlan Teklad 2020X, n=6) or a purified casein-based diet (AIN-76A; Dyets D113755, n=5) in a crossover design. Following wash-in periods, BP and RBF were recorded for 2-4 hours/day (1000 Hz) over four consecutive days. Mean arterial pressure (MAP), RBF, and renal vascular resistance (RVR = MAP/RBF) were averaged for each diet. Autoregulatory efficiency was assessed using the short-segment autoregulatory index (SSARI), where 0 reflects complete RBF compensation to BP changes and 1 reflects no compensation. SSARI was calculated across multiple segment lengths to capture time-dependent autoregulatory dynamics. Unpaired t-tests were used to compare MAP, RBF, RVR, and SSARI’s at 2.5 and 20 seconds following a BP change of at least ± 5 mmHg between diets. No significant differences were observed between diets in MAP, RBF, RVR or SSARI (all p-values > 0.7), indicating that dietary protein source did not significantly alter renal hemodynamics or BP regulation under these conditions. Future studies may determine whether dietary protein source influences autoregulatory function during renal injury or hypertension.
Start Time
15-4-2026 9:00 AM
End Time
15-4-2026 12:00 PM
Room Number
Culp Ballroom 316
Poster Number
52
Presentation Type
Poster
Presentation Subtype
Posters - Competitive
Presentation Category
Health
Student Type
Undergraduate Student
Faculty Mentor
Aaron Polichnowski
The Effect of Dietary Protein Source on Renal Hemodynamics in Conscious Rats
Culp Ballroom 316
Renal blood flow (RBF) autoregulation is an intrinsic mechanism that stabilizes RBF and glomerular filtration rate during changes in arterial blood pressure (BP), thereby protecting glomerular capillaries from barotrauma-mediated injury. Dietary protein source (e.g., plant- vs. animal-based protein) has been implicated in kidney disease susceptibility and progression, but its effects on RBF autoregulation remain unknown. This study examined whether plant-based (i.e., wheat-gluten) versus animal-based (i.e., casein) dietary protein affects mean arterial pressure (MAP), renal blood flow, and renal autoregulation in rats. We hypothesized that a diet with casein-based protein source will impair RBF autoregulatory responses to spontaneous blood pressure (BP) fluctuations in conscious rats. Male Sprague-Dawley rats (n=11) were instrumented with BP radiotelemetry transmitters and perivascular flow probes to measure BP and RBF in the conscious state. After recovery, rats received either a plant-based diet (Harlan Teklad 2020X, n=6) or a purified casein-based diet (AIN-76A; Dyets D113755, n=5) in a crossover design. Following wash-in periods, BP and RBF were recorded for 2-4 hours/day (1000 Hz) over four consecutive days. Mean arterial pressure (MAP), RBF, and renal vascular resistance (RVR = MAP/RBF) were averaged for each diet. Autoregulatory efficiency was assessed using the short-segment autoregulatory index (SSARI), where 0 reflects complete RBF compensation to BP changes and 1 reflects no compensation. SSARI was calculated across multiple segment lengths to capture time-dependent autoregulatory dynamics. Unpaired t-tests were used to compare MAP, RBF, RVR, and SSARI’s at 2.5 and 20 seconds following a BP change of at least ± 5 mmHg between diets. No significant differences were observed between diets in MAP, RBF, RVR or SSARI (all p-values > 0.7), indicating that dietary protein source did not significantly alter renal hemodynamics or BP regulation under these conditions. Future studies may determine whether dietary protein source influences autoregulatory function during renal injury or hypertension.
