Distribution of 883-S (Ceruletide diethylamine) by autoradiography in rat and mouse

Abstract

The distribution of ¹⁴C-883-S (ceruletide diethylamine) in male rats, pregnant rats and male mice was studied using a whole body autoradiography technique. The highest radioactivity was seen in many tissues at 5min after i.v. administration of 5mg/kg. The highest level of radioactivity was found in the kidney followed by the liver, pancreas, salivary gland, thyroid, lung and blood in descending order. The radioactivity of the pancreas, bone marrow, thyroid, salivary gland, pituitary gland and mucosa of the gastrointestinal tract increased gradually for 4hr and decreased slowly thereafter.
In pregnant rat, fetal radioactivity was not detected immediately after administration but increased gradually thereafter, with the highest level being observed at 24hr after administration for fetuses of both 12 and 19 days gestation. Radioactivity was still observed in mather and fetus 8 days after administration in rat of 12 days gestaion.
The distribution pattern in male mice resembled that in rat, for example, the radioactivity of the pancreas, bone mallow, salivary gland, mucosa of gastrointestinal tract, spleen and skin increased gradually for 4hr.