Electrolytes Concentration Reference Limits in Amniotic Fluid of Rabbits on 27-28 Day of Gestation

Abstract

THE AIM: to determine reference limits of volume, osmolality and concentration of Na+, K+, Cl−, non-organic phosphate (Pi ), and Ca2+ in amniotic fluid (AF) of rabbits on 27-28 day of gestation. MATERIALS AND METHODS: during research on first-pregnant rabbits (n=6), received 37 samples of AF, determined fetal mass, fetal part of placenta mass, volume, osmolality and concentration of Na+, K+, Cl−, Pi , and Ca2+. RESULTS: obtained reference limits of volume (0,09–1,63 ml), osmolality (210,0–267,0, mOsmol/kg), concentration of ions Na+ (110,0–146,0 mmol/l), K+ (6,0–12,4 mmol/l), Cl– (87,0–117,0 mmol/l), Ca2+ (1,88– 2,89 mmol/l) and Pi (0,56–1,57 mmol/l) in AF. Reverse correlation of AF volume with fetus mass (r = -0,525, p < 0,001) and positive correlation between fetus mass and AF osmolality (r = 0,375, p = 0,022) were determined. Concentrations of Na+, K+, Cl− are correlated with placenta mass (r = 0,368, p = 0,025; r = 0,353, p = 0,032; r = 0,381, p = 0,020, respectively). AF osmolality correlated with concentrations of Na+ (r = 0,514, p < 0,001) and Cl(r = 0,510, p < 0,001). CONCLUSION: results could be used for developing animal models of medicamental influence on AF volume, osmolality and ion composition on late gestation.