RT Journal Article SR Electronic(1) A1 Cantell, K. A1 Pyhälä, LiisaYR 1973 T1 Circulating Interferon in Rabbits after Administration of Human Interferon by Different Routes JF Journal of General Virology, VO 20 IS 1 SP 97 OP 104 DO https://doi.org/10.1099/0022-1317-20-1-97 PB Microbiology Society, SN 1465-2099, AB SUMMARY Human leucocyte interferon was rapidly cleared from the circulation of rabbits receiving 3 million units intravenously, but the clearance rate was greatly decreased after 1 h. The early half-time was 13 min and the late half-time 73 min. No circulating interferon was detected beyond 6 h. Repeated injections did not affect the clearance rate. Intramuscular injection of 3 million units of human or rabbit interferon maintained a relatively stable interferon level in the serum for 12 h. Higher doses raised the level and prolonged the persistence of circulating interferon. A single intramuscular injection of 30 million units of human interferon maintained a detectable interferon level in the serum for 48 h. Subcutaneous injections resulted in even longer persistence of measurable interferon in the blood. No interferon was detected in the serum after oral administration of 6 million units of human interferon., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-20-1-97