Transportation of dynamic biochemical signals in non-reversing oscillatory flows in blood vessels

Biological processes and behaviors of endothelial cells on the inner surfaces of blood vessels are regulated by the stimulation from biochemical signals contained in the blood. In this paper, the transportation of dynamic biochemical signals in non-reversing oscillatory flows in blood vessels is analyzed by numerically solving a nonlinear governing equation for the time-dependent Taylor-Aris dispersion. Results show that the nonlinear frequency-amplitude modulation of the transportation of biochemical signals is more (less) significant when the frequency of an oscillatory flow is close to (higher than) that of an oscillatory signal. Under steady flow, the transfer function for the signal transmission system is obtained, showing that the system is a low-pass filter. Lower inner radius or higher center-line velocity of a blood vessel increases the cutoff frequency of the transportation system. These results suggest the possibility and condition for the 'remote' transmission of low-frequency dynamic biochemical signals in pulsatile blood flows.