liu.seSearch for publications in DiVA
Change search
ReferencesLink to record
Permanent link

Direct link
Ontogeny of baroreflex control in the American alligator Alligator mississippiensis
University of California at Irvine.
University of California at Irvine.
Linköping University, Department of Physics, Chemistry and Biology, Zoology . Linköping University, The Institute of Technology.
2003 (English)In: Journal of Experimental Biology, ISSN 0022-0949, Vol. 206, 2895-2902 p.Article in journal (Refereed) Published
Abstract [en]

 Baroreflex regulation appears in different species at different points in embryonic development. This study was designed to understand the development of the baroreflex in embryos of the American alligator at four different points of embryonic development (60%, 70%, 80% and 90% of a total incubation period of 72 days) and in 1-week-old hatchlings. Data from a separate study on 1-year-old alligators were included for comparison. The gain of the cardiac limb of the baroreflex was calculated from heart rate changes triggered by pharmacological manipulation of arterial pressure with sodium nitroprusside and phenylephrine. The results demonstrated that a vagally mediated hypertensive baroreflex was present during the final 30% of alligator development. A hypotensive baroreflex was not present in embryos but appeared in hatchlings, mediated by a combined effect of vagal and sympathetic efferents. Absolute baroreflex gain was maximal at 80% of incubation (41.22 beats kPa–1 min–1) and dropped thereafter, reaching a minimum in 1-year-old alligators (9.69 beats kPa–1 min–1). When the baroreflex gain was normalized to resting arterial pressure and heart rate, the maximum gain was observed in 1-year-old alligators (normalized index of 2.12 versus 0.75 in hatchlings and 0.69 as the highest gain in embryos). In conclusion, baroreflex regulation appeared during embryonic development with a substantial gain. These findings indicate that embryonic development is a period of preparation for cardiovascular regulatory mechanisms that will be necessary in adult life and that the baroreflex control mechanism is required for cardiovascular control during ontogeny.   

Place, publisher, year, edition, pages
2003. Vol. 206, 2895-2902 p.
National Category
Natural Sciences
URN: urn:nbn:se:liu:diva-39749DOI: 10.1242/jeb.00486Local ID: 51113OAI: diva2:260598
baroreflex regulation, embryonic development, baroreflex gain, cardiovascular regulation, American alligator, Alligator mississippiensis
Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2010-04-14

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Altimiras, Jordi
By organisation
Zoology The Institute of Technology
In the same journal
Journal of Experimental Biology
Natural Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 38 hits
ReferencesLink to record
Permanent link

Direct link