Abstract
KUGIMIYA, T., FUJISAWA, M., SUWA, K., YAMAMURA, H., MINOHARA, K. and KASAMA, T. Effects of Ortho-Iodo-Sodium Benzoate (OISB) on Oxygen-Hemoglobin Affinity and Its Relation to Plasma Concentrations in Dogs. Tohoku J. exp. Med., 1982, 136 (1), 35-41-Effects of ortho-iodo-sodium benzoate (OISB) on oxygen-hemoglobin affinity were studied in unanesthetized beagles with simultaneous measurement of its plasma concentrations. Oxygen-hemoglobin affinity changes correlated well with the plasma concentrations of the drug. Intravenous administration of 100mg/kg of OISB increased P50 significantly from the control value of 28.6±0.8mmHg to 29.5±0.7mmHg and 30.0±0.5mmHg, 5min and 30min after the infusion, respectively. P50 gradually decreased thereafter, and after 1hr period, elevation was no longer significant. Administration of 200mg/kg of OISB caused a significant increase in P50 from the control of 29.3±0.3 mmHg to 30.5±0.4mmHg, 31.1±0.3mmHg, 31.1±0.3mmHg and 30.5±0.5 mmHg, at 5min, 30min, 1hr and 3hr, respectively. P50 elevation declined thereafter to control levels. Plasma concentrations of the drug reached its highest level 5min after the administration and declined gradually thereafter. All significant elevations of P50 were accompanied by the plasma concentrations of the drug more than 200μg/ml. Biological half-life of the drug was found to be about 5.5hr.
