Dataset Information

The effects of recruitment of renal functional reserve on renal cortical and medullary oxygenation in non-anesthetized sheep.

ABSTRACT:

Aim

Recruitment of renal functional reserve (RFR) with amino acid loading increases renal blood flow and glomerular filtration rate. However, its effects on renal cortical and medullary oxygenation have not been determined. Accordingly, we tested the effects of recruitment of RFR on renal cortical and medullary oxygenation in non-anesthetized sheep.

Methods

Under general anesthesia, we instrumented 10 sheep to enable subsequent continuous measurements of systemic and renal hemodynamics, renal oxygen delivery and consumption, and cortical and medullary tissue oxygen tension (PO₂ ). We then measured the effects of recruitment of RFR with an intravenous infusion of 500 ml of a clinically used amino acid solution (10% Synthamin® 17) in the non-anesthetized state.

Results

Compared with baseline, Synthamin® 17 infusion significantly increased renal oxygen delivery mean ± SD maximum increase: (from 0.79 ± 0.17 to 1.06 ± 0.16 ml/kg/min, p < 0.001), renal oxygen consumption (from 0.08 ± 0.01 to 0.15 ± 0.02 ml/kg/min, p < 0.001), and glomerular filtration rate (+45.2 ± 2.7%, p < 0.001). Renal cortical tissue PO₂ increased by a maximum of 26.4 ± 1.1% (p = 0.001) and medullary tissue PO₂ increased by a maximum of 23.9 ± 2.8% (p = 0. 001).

Conclusions

In non-anesthetized healthy sheep, recruitment of RFR improved renal cortical and medullary oxygenation. These observations might have implications for the use of recruitment of RFR for diagnostic and therapeutic purposes.

SUBMITTER: Jufar AH

PROVIDER: S-EPMC10909474 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature

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Publications

The effects of recruitment of renal functional reserve on renal cortical and medullary oxygenation in non-anesthetized sheep.

Jufar Alemayehu H AH Evans Roger G RG May Clive N CN Hood Sally G SG Betrie Ashenafi H AH Trask-Marino Anton A Bellomo Rinaldo R Lankadeva Yugeesh R YR

Acta physiologica (Oxford, England) 20230112 4

<h4>Aim</h4>Recruitment of renal functional reserve (RFR) with amino acid loading increases renal blood flow and glomerular filtration rate. However, its effects on renal cortical and medullary oxygenation have not been determined. Accordingly, we tested the effects of recruitment of RFR on renal cortical and medullary oxygenation in non-anesthetized sheep.<h4>Methods</h4>Under general anesthesia, we instrumented 10 sheep to enable subsequent continuous measurements of systemic and renal hemodyn ...[more]

PMID: 36598336

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Dataset Information

The effects of recruitment of renal functional reserve on renal cortical and medullary oxygenation in non-anesthetized sheep.

Aim

Methods

Results

Conclusions

Publications

The effects of recruitment of renal functional reserve on renal cortical and medullary oxygenation in non-anesthetized sheep.

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