VASCULAR PERIPHERAL RESISTANCE AND COMPLIANCE IN THE LOBSTER HOMARUS AMERICANUS
Date
1996-10-24
Journal Title
Journal ISSN
Volume Title
Publisher
Blackwell Publishing, Inc.
Abstract
The peripheral resistance to flow through each arterial
bed (in actuality, the entire pathway from the heart back
to the pericardial sinus) and the mechanical properties of
the seven arteries leaving the lobster heart are measured
and compared. Resistance is inversely proportional to
artery radius and, for each pathway, the resistance falls
non-linearly as flow rate increases. The resistance of the
hepatic arterial system is lower than that predicted on the
basis of its radius. Body-part posture and movement may
affect the resistance to perfusion of that region. The total
vascular resistance placed on the heart when each artery
is perfused at a rate typical of in vivo flow rates is
approximately 1.93 kPa s ml−1. All vessels exhibit
adluminal layers of fibrils and are relatively compliant at
pressures at or below heart systolic pressure. Arteries
become stiffer at pressures greater than peak systolic
pressure and at radii greater than twice the unpressurized
radius. The dorsal abdominal artery possesses striated
muscle in the lateral walls. This artery remains compliant
over the entire range of hemolymph pressures expected in
lobsters. These trends are illustrated when the
incremental modulus of elasticity is compared among
arteries. All arteries should function as Windkessels to
damp the pulsatile pressures and flows generated by the
heart. The dorsal abdominal artery may also actively
regulate its flow.
Description
Keywords
Biology
Citation
JERREL L. WILKENS, GLEN W. DAVIDSON AND MICHAEL J. CAVEY "VASCULAR PERIPHERAL RESISTANCE AND COMPLIANCE IN THE LOBSTER HOMARUS AMERICANUS" The Journal of Experimental Biology 200, 477–485 (1997)