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 Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by JONES, D. R. Articles by MENSE, D. C. Search for Related Content PubMed Articles by JONES, D. R. Articles by MENSE, D. C.

Journal of Experimental Biology 120,201-213 (1986)
Published by Company of Biologists 1986

The Influence of Blood Gas Properties on Gas Tensions and pH of Ventral and Dorsal Aortic Blood in Free-Swimming Tuna, Euthynnus Affinis

DAVID R. JONES ¹, RICHARD W. BRILL ², and DENNIS C. MENSE ¹

¹ Department of Zoology, University of British Columbia, Vancouver, B.C., Canada V6T2A9
² Southwest Fisheries Center Honolulu Laboratory, National Marine Fisheries Service, National Oceanographic and Atmospheric Administration, Honolulu, Hawaii 96182, U.S.A.

We have developed a technique for capture, anaesthetization, instrumentation and release of tuna and have made the first determinations of blood gas values in dorsal and ventral aortae of free-swimming tuna. Dorsal aortic P_o2 varied from 34.5 to 91.7 mmHg, and P_coco2 ranged from 3.7 to 7mmHg. Dorsal aortic blood [pHa = 7.77 ± 0.04 (8), mean ± one S.E.M. (N)] was more alkaline than ventral aortic blood [pHv = 7.65 ± 0.02 (7)]. Warming dorsal aortic blood from 25 to 35 °C in a closed system caused Po₂ and P_COCO2 to rise and pH to fall. Oxygen-combining curves forwhole blood were sigmoid [mean Hill's number = 1.72 ± 0.05 (11), range 1.57-2.0]and P₅₀ over the pH range found in free-swimming animals was 21 ± 1.75(8) mmHg. The CO₂-induced Bohr coefficient (logP₅₀/ pH) was -0.59 ± 0.046(30). Unusual features of CO₂-combining curves are attributed to a significant Rooteffect. Although these in vitro properties of tuna whole blood are at variance withother published data on tuna they nevertheless substantiate our determinations madein vivo.