|
|
||||||||
AJP - Regulatory, Integrative and Comparative Physiology, Vol 268, Issue 5 1273-R1280, Copyright © 1995 by American Physiological Society
ARTICLES |
G. Y. Oudit and D. G. Butler
Department of Zoology, University of Toronto, Ontario, Canada.
The effects of 150 ng/kg iv injections of arginine vasotocin (AVT), eel atrial natriuretic peptide (ANP), and epinephrine (Epi) on the cardiovascular dynamics of resting freshwater eels, Anguilla rostrata were studied. Injection of AVT into the caudal vein significantly increased cardiac output (CO) from 15.3 to 23.6 ml.min-1.kg-1 primarily by increasing stroke volume. Mean dorsal aortic pressure (PDA) also increased. Estimated branchial shunting (2.54 ml.min-1.kg-1) was elevated by 130% because of an increased proportion of CO, indicating a vasoconstriction of the branchial arterioarterial pathway. In contrast, Epi reduced the fraction of CO perfusing the arteriovenous pathway. Epi also produced a positive chronotropic effect, increased CO and systemic vasoconstriction, resulting in a vasopressor response. These changes occurred earlier than those of AVT and ANP. Pressor responses triggered by AVT and Epi preceded the increases in CO. Injections of 150 and 200 ng/kg ANP caused a reduction in PDA due to a decrease in CO (and SV) but failed to modulate systemic resistance. The change in CO was the primary contributor to the pressor (and depressor) responses elicited by the three hormones.
This article has been cited by other articles:
![]() |
S. Nobata, M. Ogoshi, and Y. Takei Potent cardiovascular actions of homologous adrenomedullins in eels Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2008; 294(5): R1544 - R1553. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. H. Evans, P. M. Piermarini, and K. P. Choe The Multifunctional Fish Gill: Dominant Site of Gas Exchange, Osmoregulation, Acid-Base Regulation, and Excretion of Nitrogenous Waste Physiol Rev, January 1, 2005; 85(1): 97 - 177. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Tervonen, H. Ruskoaho, T. Lecklin, M. Ilves, and O. Vuolteenaho Salmon cardiac natriuretic peptide is a volume-regulating hormone Am J Physiol Endocrinol Metab, August 1, 2002; 283(2): E353 - E361. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |