Fig. 5
From: Non-invasive quantification of cardiac stroke volume in the edible crab Cancer pagurus
Time courses of heart rate of C. pagurus under different levels of water PO2. Heart rates were recorded with IR photo-plethysmographs at 12 °C water temperature. After at least 15 h of normoxic control, water PO2 was reduced to 15% air saturation by adding N2 gas. Hypoxic conditions were maintained for 6 h, after which the aeration was switched back to ambient air. a and b are two runs on animal 1, separated by one week of recovery; c = animal 2; d = animal 3. Note, the different/variable pattern under normoxic conditions, in contrast to hypoxia