Effects of nitrite exposure on blood respiratory properties, acid-base and electrolyte regulation in the carp (Cyprinus carpio) (original) (raw)

Summary

Adult carp were subjected to 1 m_M_ environmental nitrite for 48 h and nitrite uptake and changes in blood respiratory properties, extracellular electrolyte composition and acid-base status were examined.

A constant influx of nitrite caused an accumulation of NO −2 in plasma to 5.4 m_M_ in 48 h. The fraction of methaemoglobin rose with plasma [NO −2 ] to 83%, and the arterial oxygen content decreased to extremely low values. Arterial\(P_{{\text{O}}_2 }\) increased as a compensation to this O2-shortage, whereas the O2 saturation of the functional (unoxidized) haemoglobin decreased, revealing a reduction in its O2 affinity.

Blood haematocrit decreased as a result of red cell shrinkage, which caused very high red cell haemoglobin (Hb) concentrations. The erythrocytic nucleoside triphosphate (NTP) concentration showed a parallel increase whereby NTP/Hb, as well as the relative contributions of ATP and GTP to NTP, remained unchanged.

Plasma [Cl−] declined by 15 m_M_ in 48 h, off-setting the plasma [NO −2 ] increase, minor changes in plasma [HCO −3 ] and a considerable increase in plasma [lactate]. Arterial pH and [HCO −3 ] rose slightly during the first 24 h of nitrite exposure, but returned to control values at 48 h. The rise in plasma [lactate] was not reflected in an extracellular metabolic acidosis. Plasma [K+] increased by 94% in 48 h, revealing an uncompensated extracellular hyperkalemia, whereas plasma [Na+] decreased, and plasma [Ca++] was unchanged. Plasma osmolality remained essentially constant.

The NO −2 accumulation could be reversed by transfer of the fish to NO −2 -free water, but nitrite ‘off-loading’ was slower than the preceding NO −2 loading.

Access this article

Log in via an institution

Subscribe and save

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

Abbreviations

Hb:

hemoglobin

NTP :

nucleoside triphosphate

Hct :

hematocrit

\(S_{{\text{O}}_2 }\) :

fractional saturation of Hb with oxygen

References

Download references

Author information

Author notes

  1. Frank B. Jensen
    Present address: Institute of Biology, Odense University, DK-5230, Odense M, Denmark

Authors and Affiliations

  1. Abteilung Physiologie, Max-Planck-Institut für experimentelle Medizin, D-3400, Göttingen, Federal Republic of Germany
    Frank B. Jensen, Niels A. Andersen & Norbert Heisler

Authors

  1. Frank B. Jensen
    You can also search for this author inPubMed Google Scholar
  2. Niels A. Andersen
    You can also search for this author inPubMed Google Scholar
  3. Norbert Heisler
    You can also search for this author inPubMed Google Scholar

Rights and permissions

About this article

Cite this article

Jensen, F.B., Andersen, N.A. & Heisler, N. Effects of nitrite exposure on blood respiratory properties, acid-base and electrolyte regulation in the carp (Cyprinus carpio).J Comp Physiol B 157, 533–541 (1987). https://doi.org/10.1007/BF00700972

Download citation

Keywords