Swimming performance, venous oxygen tension and cardiac performance of coronary-ligated rainbow trout, Oncorhynchus mykiss, exposed to progressive hypoxia.

J F Steffensen; A P Farrell

Swimming performance, venous oxygen tension and cardiac performance of coronary-ligated rainbow trout, Oncorhynchus mykiss, exposed to progressive hypoxia.

J F Steffensen, A P Farrell

Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › peer review

72 Citationer (Scopus)

Abstract

Udgivelsesdato: 1998-Feb

Originalsprog	Engelsk
Tidsskrift	Comparative Biochemistry and Physiology A
Vol/bind	119
Udgave nummer	2
Sider (fra-til)	585-92
Antal sider	7
ISSN	1095-6433
Status	Udgivet - 1998

Bibliografisk note

Keywords: Animals; Anoxia; Aorta; Blood Pressure; Body Weight; Coronary Circulation; Coronary Disease; Fatigue; Heart Rate; Ligation; Oncorhynchus mykiss; Oxygen; Partial Pressure; Swimming; Veins

Citationsformater

@article{3a2f15b0893111dd9c20000ea68e967b,

title = "Swimming performance, venous oxygen tension and cardiac performance of coronary-ligated rainbow trout, Oncorhynchus mykiss, exposed to progressive hypoxia.",

abstract = "We performed in vivo studies to examine the idea that cardiac work is impaired in rainbow trout (Oncorhynchus mykiss) below a certain venous PO2 threshold. We hypothesized that coronary-ligated fish, swimming continuously at a reasonably high water velocity (1.5 body lengths x s(-1)) and exposed to progressive hypoxia, would fatigue at higher venous PO2 and ambient water PO2 compared with sham-operated fish. However, we found that both the lowest venous PO2 that supported hypoxic swimming (9.9 torr for coronary-ligated fish and 11.1 torr for sham-operated fish) and the venous PO2 at fatigue (7.8 torr and 8.6 torr, respectively) were the same for coronary-ligated and sham-operated fish. Also, both groups quit swimming at the same water PO2 heart rate and hematocrit. Nevertheless, significant differences in cardiac performance did exist between the two groups. Whereas ventral aortic blood pressure (Pva) increased significantly with hypoxic swimming in sham-operated fish, there was no such increase in coronary-ligated fish. In addition, cardiac arrhythmias occurred in coronary-ligated fish at fatigue, and these fish were slower to recover from exhaustion. We believe that the venous PO2 threshold to support cardiac performance in the absence of a coronary supply was between 7.8 and 9.9 torr. Furthermore, we suspect that the low PO2 in coronary-ligated fish effectively lowered their myocardial O2 demand. Uncertainty still exists regarding whether or not the venous PO2 threshold lies between 8.6 and 11.1 torr in sham-operated fish.",

author = "Steffensen, {J F} and Farrell, {A P}",

note = "Keywords: Animals; Anoxia; Aorta; Blood Pressure; Body Weight; Coronary Circulation; Coronary Disease; Fatigue; Heart Rate; Ligation; Oncorhynchus mykiss; Oxygen; Partial Pressure; Swimming; Veins",

year = "1998",

language = "English",

volume = "119",

pages = "585--92",

journal = "Comparative biochemistry and physiology. Part A, Molecular & integrative physiology",

issn = "1095-6433",

publisher = "Elsevier",

number = "2",

}

TY - JOUR

T1 - Swimming performance, venous oxygen tension and cardiac performance of coronary-ligated rainbow trout, Oncorhynchus mykiss, exposed to progressive hypoxia.

AU - Steffensen, J F

AU - Farrell, A P

N1 - Keywords: Animals; Anoxia; Aorta; Blood Pressure; Body Weight; Coronary Circulation; Coronary Disease; Fatigue; Heart Rate; Ligation; Oncorhynchus mykiss; Oxygen; Partial Pressure; Swimming; Veins

PY - 1998

Y1 - 1998

N2 - We performed in vivo studies to examine the idea that cardiac work is impaired in rainbow trout (Oncorhynchus mykiss) below a certain venous PO2 threshold. We hypothesized that coronary-ligated fish, swimming continuously at a reasonably high water velocity (1.5 body lengths x s(-1)) and exposed to progressive hypoxia, would fatigue at higher venous PO2 and ambient water PO2 compared with sham-operated fish. However, we found that both the lowest venous PO2 that supported hypoxic swimming (9.9 torr for coronary-ligated fish and 11.1 torr for sham-operated fish) and the venous PO2 at fatigue (7.8 torr and 8.6 torr, respectively) were the same for coronary-ligated and sham-operated fish. Also, both groups quit swimming at the same water PO2 heart rate and hematocrit. Nevertheless, significant differences in cardiac performance did exist between the two groups. Whereas ventral aortic blood pressure (Pva) increased significantly with hypoxic swimming in sham-operated fish, there was no such increase in coronary-ligated fish. In addition, cardiac arrhythmias occurred in coronary-ligated fish at fatigue, and these fish were slower to recover from exhaustion. We believe that the venous PO2 threshold to support cardiac performance in the absence of a coronary supply was between 7.8 and 9.9 torr. Furthermore, we suspect that the low PO2 in coronary-ligated fish effectively lowered their myocardial O2 demand. Uncertainty still exists regarding whether or not the venous PO2 threshold lies between 8.6 and 11.1 torr in sham-operated fish.

AB - We performed in vivo studies to examine the idea that cardiac work is impaired in rainbow trout (Oncorhynchus mykiss) below a certain venous PO2 threshold. We hypothesized that coronary-ligated fish, swimming continuously at a reasonably high water velocity (1.5 body lengths x s(-1)) and exposed to progressive hypoxia, would fatigue at higher venous PO2 and ambient water PO2 compared with sham-operated fish. However, we found that both the lowest venous PO2 that supported hypoxic swimming (9.9 torr for coronary-ligated fish and 11.1 torr for sham-operated fish) and the venous PO2 at fatigue (7.8 torr and 8.6 torr, respectively) were the same for coronary-ligated and sham-operated fish. Also, both groups quit swimming at the same water PO2 heart rate and hematocrit. Nevertheless, significant differences in cardiac performance did exist between the two groups. Whereas ventral aortic blood pressure (Pva) increased significantly with hypoxic swimming in sham-operated fish, there was no such increase in coronary-ligated fish. In addition, cardiac arrhythmias occurred in coronary-ligated fish at fatigue, and these fish were slower to recover from exhaustion. We believe that the venous PO2 threshold to support cardiac performance in the absence of a coronary supply was between 7.8 and 9.9 torr. Furthermore, we suspect that the low PO2 in coronary-ligated fish effectively lowered their myocardial O2 demand. Uncertainty still exists regarding whether or not the venous PO2 threshold lies between 8.6 and 11.1 torr in sham-operated fish.

M3 - Journal article

C2 - 11249006

VL - 119

SP - 585

EP - 592

JO - Comparative biochemistry and physiology. Part A, Molecular & integrative physiology

JF - Comparative biochemistry and physiology. Part A, Molecular & integrative physiology

SN - 1095-6433

IS - 2

ER -