PORTAL CIRCULATIONS AND THEIR RELATION TO COUNTERCURRENT SYSTEMS
Open Access
- 10 October 1978
- journal article
- research article
- Published by Wiley in Quarterly Journal of Experimental Physiology and Cognate Medical Sciences
- Vol. 63 (4) , 355-369
- https://doi.org/10.1113/expphysiol.1978.sp002448
Abstract
We have reviewed the distribution of portal circulations throughout the animal body; they are commoner than is generally supposed. Most portal circulations consist of two serial capillary beds connected by one or more larger vessels. We have called these ‘convergent’ portal circulations: examples are hepatic portal, placental, hypophysial, renal, ovarian and testicular circulations, as are parts of the lymphatic circulation. A second type of portal circulation, which is less common, consists of two serial capillary beds that are not connected by larger vessels. These we have called ‘continuous’ portal circulations: adrenal and pancreatic circulations are examples of this type. When a countercurrent concentrating mechanism exists in the body it is always part of the primary or secondary bed of a convergent portal circulation, though some convergent portal circulations are not associated with countercurrent mechanisms.This publication has 0 references indexed in Scilit: