Intravascular Circulation and Distribution of Human 51CR-DBBF Stroma-Free Hemoglobin, 51CR-Plasma, 51-CR-Saline, 59FE-Plasma, and 125I-Albumin in the Mouse.

Male B6C3HFl mice were infused with 51Cr labeled DBBF bis 3,5-dibromosalicyl fumarate crosslinked stroma-free hemoglobin SFH. The intravascular halftime T50 of SFH, determined from plasma hemoglobin levels, was 0.5 hours in the first 10 minutes and 4.3 hours during the next 50 minutes. Twenty-four hours post-infusion, less than 5 of the SFH remained. Elution on of 51Cr was reflected in a lower T50 determined from the radioactivity levels during the first 10 minutes the T50 was 0.3 hours in the next 50 minutes it was 1 hour. In the first hour following SFH infusion, 11.2 of the infused radioactivity was sequestered in the skin, 11.4 in muscle, 9.1 in the skeleton, and 5 in the liver. Twenty-four hours after infusion, 15.4 of the radioactivity was sequestered in the skin, 10.3 in the muscle, 16.6 in the skeleton and 6.7 in the liver. Within the first 24 hours after infusion, the percentages of infused radioactivity in the gastrointestinal tract and kidney ranged from 3.5 to 5.5, less than 0.4 was found in the spleen and lung, 25 was found in the urine, and 3 in feces. The circulation and distribution of 51Cr-labeled DBBF-SFH were compared to the values for 51Cr labeled plasma, 51Cr in saline, 59Fe labeled plasma, and 125I albumin. The radioactivity in the intravascular circulation was similar for 51Cr-DBBF-SFH, 51Cr-plasma, and 59Fe-plasma. Within the 24-hour post-transfusion period, the percentage of 125I-albumin in the circulation was significantly higher than that of 51Cr-DBBF-SFH. Only 10 of the 51Cr radioactivity was present in the plasma ten minutes following the infusion. During the 24-hour post-infusion period, extravascular distribution of the 51Cr-saline, 51Cr-plasma, and 125I-albumin within the organs was similar to that of 51Cr-DBBF-SFH levels were highest in skin, muscle, skeleton and liver levels in lung and spleen were not increased.