caa a22 4500 465826164 CHVBK 20180323112149.0 cr unu---uuuuu 170327e19901101xx s 000 0 eng 10.1007/BF00691714 doi (NATIONALLICENCE)springer-10.1007/BF00691714 Absence of adrenergic red cell pH and oxygen content regulation in American eel ( Anguilla rostrata ) during hypercapnic acidosis in vivo and in vitro [Elektronische Daten] [D. Hyde, S. Perry] Summary: American eels (Anguilla rostrata) were exposed to acute (30 min) external hypercapnia (1% CO2 or 5% CO2 in air) in order to assess the involvement of circulating catecholamines in regulating red blood cell (RBC) pH and oxygen content during whole blood acidosis. Plasma adrenaline levels increased approximately 5-fold during severe hypercapnia yet absolute levels remained below 1.0 nM; plasma noradrenaline levels were unchanged. Both RBC pH and oxygen bound to haemoglobin ([O2]/[Hb]) conformed to in vitro relationships with whole blood pH (pHe) indicating absence of regulation during hypercapnia in vivo. Pre-treatment of eels with α- or β-adrenoceptor antagonists, phentolamine or propranolol was without effect on RBC pH or [O2]/[Hb] during hypercapnia. Further, intra-arterial injection of adrenaline (final plasma concentration=134 nM) or noradrenaline (final plasma concentration = 34 nM) into hypercapnic eels 5 min prior to blood sampling did not modify any measured blood variable RBC nucleoside triphosphate (NTP) levels, RBC pH and [O2]/[Hb]. In vitro, the application of adrenaline or noradrenaline to eel RBC's during graded normoxic hypercapnia or hypoxic hypercapnia (noradrenaline only) did not affect RBC pH significantly. RBC NTP levels were depressed by noradrenaline in vitro but only during hypoxic hypercapnia. The results demonstrate adrenergic insensitivity of eel RBC's in vivo even under conditions (acidosis, hypoxemia) known to enhance catecholamine-mediated RBC responses in other species. We conclude that the American eel has no capacity to regulate RBC pH during hypercapnia and consequently [O2]/[Hb] is reduced in accordance with the in vitro Root effect. Springer-Verlag, 1990 Adrenaline nationallicence Noradrenaline nationallicence Red blood cell nationallicence Oxygen nationallicence Hypercapnia nationallicence Nucleoside triphosphate nationallicence Anguilla rostrata nationallicence Hyde D. Department of Biology, University of Ottawa, 30 Somerset St. E., K1N 6N5, Ottawa, Ontario, Canada aut Perry S. Department of Biology, University of Ottawa, 30 Somerset St. E., K1N 6N5, Ottawa, Ontario, Canada aut Journal of Comparative Physiology B Springer-Verlag 159/6(1990-11-01), 687-693 0174-1578 159:6<687 1990 159 360 https://doi.org/10.1007/BF00691714 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00691714 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hyde D. Department of Biology, University of Ottawa, 30 Somerset St. E., K1N 6N5, Ottawa, Ontario, Canada aut NATIONALLICENCE 700 1- Perry S. Department of Biology, University of Ottawa, 30 Somerset St. E., K1N 6N5, Ottawa, Ontario, Canada aut NATIONALLICENCE 773 0- Journal of Comparative Physiology B Springer-Verlag 159/6(1990-11-01), 687-693 0174-1578 159:6<687 1990 159 360 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer