Functional morphology of the vascular plexuses associated with the cetacean uterus
Version of Record online: 8 FEB 2005
Copyright © 1993 Wiley-Liss, Inc.
The Anatomical Record
Volume 237, Issue 4, pages 538–546, December 1993
How to Cite
Rommel, S. A., Ann Pabst, D. and McLellan, W. A. (1993), Functional morphology of the vascular plexuses associated with the cetacean uterus. Anat. Rec., 237: 538–546. doi: 10.1002/ar.1092370414
- Issue online: 8 FEB 2005
- Version of Record online: 8 FEB 2005
- Manuscript Accepted: 26 JUL 1993
- Manuscript Received: 21 APR 1993
- Countercurrent heat exchange;
- Fetal development;
- Reproductive system;
- Vascular plexus
The cetacean reproductive system is surrounded by thermogenic locomotory muscle and insulating blubber. This arrangement suggests elevated temperatures at the uterus that could induce detrimental effects on fetal development. We present anatomical evidence for a complex countercurrent heat exchange system that could function to regulate the thermal environment of the uterus and a developing fetus. Cooled venous blood from the surfaces of the dorsal fin and flukes enters the abdominal cavity via the lumbo-caudal venous plexus. This plexus is juxtaposed to the arterial and venous plexuses associated with the uterus. The morphology of the lumbo-caudal venous plexus suggests that it acts as a “heat sink” for the adjacent tissues. Heat may be transferred to the cool, lumbo-caudal venous plexus from the warm blood in the arterial and venous plexuses supplying the uterus. Heat may also be transferred from adjacent locomotory muscles to the cool lumbo-caudal venous plexus. The countercurrent heat exchanger created by the juxtaposition of the lumbo-caudal venous plexus with the uterovarian arterial plexus is similar in design to that of the countercurrent heat exchanger described for male cetaceans. The functional implications of introducing cool superficial blood into the abdominal cavity of a diving, and locomoting female cetacean are discussed. © 1993 Wiley-Liss, Inc.