Table 1.

Concentrations of urea and glucose in plasma and organs of Rana sylvatica administered saline or saline containing urea, and sampled before or after freezing at –4°C

Urea Glucose
Saline treatedUrea loadedSaline treatedUrea loaded
Unfrozen
   Plasma9.8±0.869.6±2.5*1.9±0.42.4±0.2
   Heart14.6±1.580.6±5.3*1.7±0.41.7±0.3
   Liver15.7±2.872.1±5.3*3.9±0.44.1±0.3
   Muscle12.1±1.747.8±5.9*1.0±0.21.3±0.1
Frozen/thawed
   Plasma11.7±1.560.4±2.0*28.1±2.042.3±3.8*
   Heart18.7±3.556.2±1.1*18.6±2.153.7±3.9*
   Liver21.1±3.657.2±1.6*19.9±2.169.9±10.9*
   Muscle19.5±3.356.1±2.2*18.1±2.640.9±2.9*
  • Concentrations of urea and glucose in plasma are μmol ml-1 and in organs are μmol g–1 fresh tissue. Values are means± s.e.m.; N=5 frogs per group

    Asterisk denotes that the mean for the urea-loaded group differed significantly (P<0.05) from its saline-treated counterpart