Effect of Serum Unbound Iron-Binding Capacity on the Tissue Distribution of ⁶⁷Ga in Abscess-Bearing Rabbits

Summary

The effect of serum unbound iron-binding capacity (UIBC) on the blood clearance and tissue distribution in abscessbearing rabbits was studied. In rabbits with low serum UIBC (95 ± 28 μg/dl), the blood clearance of ⁶⁷Ga was much faster than that of rabbits with high serum UIBC (306 ± 27 μg/dl). The ⁶⁷Ga uptake by the liver, spleen, kidney, muscle, bone marrow or abscess 24 hrs after injection was also much lower in rabbits with low serum UIBC. In contrast, the ⁶⁷Ga deposition in bone was much higher in rabbits with low serum UIBC. Since the amounts of ⁶⁷Ga in muscle and blood were disproportionally lower than that in the abscess, the abscess-to-muscle or abscess-to-blood ratio was much higher in rabbits with low serum UIBC than that of rabbits with high serum UIBC.

Zusammenfassung

Es wurde der Einfluß der ungebundenen Eisen-Bindungs-Kapazität des Serums (UEBK) auf die Blut-Clearance sowie die Verteilung von ⁶⁷Ga in verschiedenen Geweben von Kaninchen mit experimentellen Abszessen untersucht. Die ⁶⁷Ga Blut-Clearance war bei Tieren mit niedriger UEBK (95 ± 28 μg/dl) bedeutend schneller als bei solchen mit hoher UEBK (306 ± 27 μg/dl). Die ⁶⁷Ga-Aufnahme in Leber, Milz, Nieren, Muskeln, Knochenmark und im Abszeß war 24 Std. nach der Injektion ebenfalls bedeutend niedriger bei Kaninchen mit niedriger UEBK. In Knochen hingegen war bei Tieren mit niedriger UEBK die ⁶⁷Ga-Ablagerung sehr viel größer. Da die ⁶⁷Ga-Konzentration in Muskel und Blut unverhältnismäßig niedriger als im Abszeß war, war das Verhältnis Abszeß zu Muskel bzw. Abszeß zu Blut bedeutend höher bei Kaninchen mit niedriger als bei solchen mit hoher UEBK.

* Dr. Tsan is a recipient of a Research Career Development Award (AI-00194) from the National Institute of Allergy and Infectious Diseases.

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