QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by SATCHELL, G. H. Articles by JOHNES, M. P. Search for Related Content PubMed PubMed Citation Articles by SATCHELL, G. H. Articles by JOHNES, M. P.

Journal of Experimental Biology 46,373-382 (1967)
Published by Company of Biologists 1967

The Function of the Conus Arteriosus in the Port Jackson Shark, Heterodontus Portusjacksoni

G. H. SATCHELL ¹ and M. P. JOHNES ¹

¹ School of Biological Sciences, University of Sydney

1. Blood pressure recordings were made above and below each of the three tiers of valves in the conus of Heterodontus portusjacksoni. Flow in the ventral aorta was recorded with an electromagnetic flow-meter.

2. It was shown that the lower conal valves close first and that this closure occurred before the end of ventricular systole.

3. The middle conal valves closed before the lower ones opened. The closure of both of these sets of valves was caused in part by the circumferential decrease due to conus systole, and in part by the back flow this engendered.

4. The upper conal valves closed as the middle ones opened at the end of conal systole.

5. Paralysing the conus with topical tricain rendered the lower and middle conal valves incompetent and caused the upper conal valves to be closed following ventricular relaxation with an increase in back flow.

6. The hypothesis is advanced that the conus serves to postpone the closure of the upper tier of valves until the negative intrapericardial pressure generated by ventricular ejection has decayed to a lower value.

This article has been cited by other articles:

				A. F. M. MOORMAN and V. M. CHRISTOFFELS Cardiac Chamber Formation: Development, Genes, and Evolution Physiol Rev, October 1, 2003; 83(4): 1223 - 1267. [Abstract] [Full Text] [PDF]