TY - JOUR
T1 - Effect of intravenous administration of sodium-lactate on retinal blood flow in healthy subjects
AU - Garhöfer, Gerhard
AU - Zawinka, Claudia
AU - Resch, Hemma
AU - Menke, Marcel
AU - Schmetterer, Leopold
AU - Dorner, Guido T.
PY - 2003/9/1
Y1 - 2003/9/1
N2 - PURPOSE. The present study was designed to investigate the effect of intravenously administered sodium lactate on ocular blood flow. METHODS. Twelve healthy male volunteers received either sodium lactate (0.6 mol/L) or physiologic saline solution in a randomized, double-masked, two-way crossover study. Sodium lactate or placebo were administered at an infusion speed of 500 and 1000 mL/h for 30 minutes each. Blood flow measurements were performed in the last 10 minutes of the infusion periods. Retinal blood flow was calculated based on the measurement of maximum erythrocyte velocity, assessed with bidirectional laser Doppler velocimetry, and retinal vessel diameter obtained with a retinal vessel analyzer. Choroidal blood flow was assessed with laser Doppler flowmetry and laser interferometric measurement of fundus pulsation amplitude, RESULTS. Administration of lactate increased blood lactate concentration from 1.3 ± 0.4 to 3.9 ± 0.7 mmol/L (P < 0.001) and to 7.1 ± 1.4 mmol/L (P < 0.001) at infusion speeds of 500 and 1000 mL/h, respectively. At these blood lactate concentrations, retinal blood flow increased by 15% ± 20% and by 24% ± 37% (ANOVA, P = 0.01). Fundus pulsation amplitude increased by 3% ± 6% and 10% ± 5% (ANOVA, P = 0.04) at the two plasma lactate concentrations. Subfoveal choroidal blood flow measured with laser Doppler flowmetry tended to increase by 10% ± 15% and 13% ± 20% (ANOVA, P = 0.19), but this effect was not significant. Infusion of sodium lactate induced alkalosis in arterial blood taken from the earlobe (7.41 ± 0.03 at baseline; 7.50 ± 0.03 during lactate infusion; P = 0.001). CONCLUSIONS. The data indicate that intravenously administered sodium lactate increases retinal blood flow. Whether this is related to a cytosolic redox impairment or to other hitherto unidentified mechanism remains to be clarified. Further studies are needed to determine whether lactate plays a role in regulation of choroidal blood flow.
AB - PURPOSE. The present study was designed to investigate the effect of intravenously administered sodium lactate on ocular blood flow. METHODS. Twelve healthy male volunteers received either sodium lactate (0.6 mol/L) or physiologic saline solution in a randomized, double-masked, two-way crossover study. Sodium lactate or placebo were administered at an infusion speed of 500 and 1000 mL/h for 30 minutes each. Blood flow measurements were performed in the last 10 minutes of the infusion periods. Retinal blood flow was calculated based on the measurement of maximum erythrocyte velocity, assessed with bidirectional laser Doppler velocimetry, and retinal vessel diameter obtained with a retinal vessel analyzer. Choroidal blood flow was assessed with laser Doppler flowmetry and laser interferometric measurement of fundus pulsation amplitude, RESULTS. Administration of lactate increased blood lactate concentration from 1.3 ± 0.4 to 3.9 ± 0.7 mmol/L (P < 0.001) and to 7.1 ± 1.4 mmol/L (P < 0.001) at infusion speeds of 500 and 1000 mL/h, respectively. At these blood lactate concentrations, retinal blood flow increased by 15% ± 20% and by 24% ± 37% (ANOVA, P = 0.01). Fundus pulsation amplitude increased by 3% ± 6% and 10% ± 5% (ANOVA, P = 0.04) at the two plasma lactate concentrations. Subfoveal choroidal blood flow measured with laser Doppler flowmetry tended to increase by 10% ± 15% and 13% ± 20% (ANOVA, P = 0.19), but this effect was not significant. Infusion of sodium lactate induced alkalosis in arterial blood taken from the earlobe (7.41 ± 0.03 at baseline; 7.50 ± 0.03 during lactate infusion; P = 0.001). CONCLUSIONS. The data indicate that intravenously administered sodium lactate increases retinal blood flow. Whether this is related to a cytosolic redox impairment or to other hitherto unidentified mechanism remains to be clarified. Further studies are needed to determine whether lactate plays a role in regulation of choroidal blood flow.
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U2 - 10.1167/iovs.02-1272
DO - 10.1167/iovs.02-1272
M3 - Article
C2 - 12939317
AN - SCOPUS:18244417061
SN - 0146-0404
VL - 44
SP - 3972
EP - 3976
JO - Investigative Ophthalmology and Visual Science
JF - Investigative Ophthalmology and Visual Science
IS - 9
ER -