Table 2.

Haemodynamic effects of ET-1, ETB-antagonist, tezosentan and ET-1 before and after ETB- and general ET-receptor blockade in the freshwater turtle, Trachemys scripta (Protocol 2)

Psys (kPa)sys (ml min-1 kg-1)Gsys (ml kPa-1 min-1 kg-1)Ppul (kPa)pul (ml min-1 kg-1)Gpul (ml kPa-1 min-1 kg-1)fh (min-1)tot (ml min-1 kg-1)Vstot (ml kg-1)
Resting4.0±0.442.7±10.410.7±2.32.9±0.384.7±23.726.3±9.935.9±5.6128.3±36.94.5±1.6
ET-12.5±0.2*65.0±15.825.2±5.3*2.0±0.4*59.1±21.8*26.1±9.639.7±3.0126.7±40.73.3±0.9
Resting4.1±0.433.1±7.68.3±1.52.8±0.479.7±21.326.5±9.731.5±6.4114.6±29.65.3±2.1
ETB-antagonist4.4±0.4*35.1±7.17.9±1.33.0±0.489.0±23.5*28.2±9.731.5±5.5126.0±31.7*5.1±1.6
Resting4.5±0.435.0±7.07.8±1.22.9±0.486.8±22.427.7±9.431.1±5.4123.7±30.45.1±1.6
ET-14.4±0.437.6±8.38.6±1.53.0±0.389.5±24.527.6±9.131.4±5.4129.1±33.95.2±1.6
Resting4.7±0.227.7±7.06.0±1.52.9±0.384.3±17.127.1±7.729.6±6.3114.8±21.46.3±2.7
Tezosentan4.5±0.230.5±7.67.0±2.13.0±0.379.0±5.825.6±4.632.4±6.4112.3±13.45.3±2.1
Resting4.5±0.230.1±7.56.9±2.03.0±0.279.0±6.125.7±4.732.2±6.3111.9±13.65.3±2.1
ET-14.5±0.131.2±7.26.9±1.73.0±0.282.6±8.326.8±4.931.9±6.1116.4±16.15.3±2.0
N 555343544
  • Values are mean ± s.e.m.

    Psys, mean systemic arterial pressure; sys, systemic blood flow; Gsys, systemic conductance; Ppul, mean pulmonary arterial pressure; pul, pulmonary blood flow; Gpul, pulmonary conductance; fh, heart rate; tot, total cardiac output; Vstot, total stroke volume.

    ET-1, endothelin-1 (120 pmol kg-1); ETB-antagonist (0.15 μmol kg-1); tezosentan (15.4 μmol kg-1).

  • * denotes a significant difference from resting values (P<0.05)