| Cardiac preload (central venous; pressure, Pcv), mean circulatory filling pressure (MCFP), dorsal aortic blood pressure (P-DA) and relative cardiac output (Q) were measured in sea bass (Dicentrarchus labrax) at rest and while swimming at 1 and 2 BL s(-1). MCFP, an index of venous capacitance and the upstream venous pressure driving the return of venous blood to the heart, was measured as the plateau in Pcv during ventral aortic occlusion. Compared with resting values, swimming at 1 and 2BL s(-1) increased Q (by 15 +/- 1.5 and 38 +/- 6.5%, respectively), Pcv (from 0.11 +/- 0.01 kPa to 0.12 +/- 0.01 and 0.16 +/- 0.02 kPa, respectively), MCFP (from 0.27 +/- 0.02 kPa to 0.31 +/- 0.02 and 0.40 +/- 0.04 kPa, respectively) and the calculated pressure gradient for... |
