Pentoxifylline Does Not Spare Acute Radiation Reactions in Rat Lung and Skin

• Published in: Radiation research 1992-01, Vol.129 (1), p.107-111
• Main Authors: Ward, William F., Kim, Yoon T., Molteni, Agostino, Chung-hsin Ts'ao, Hinz, Joann M.
• Format: Article
• Language: English
• Subjects: Acute lung injury; Administration, Oral; Animals; Biological and medical sciences; Biological effects of radiation; Diet; Dosage; Enzymes; Fundamental and applied biological sciences. Psychology; Hair removal; Ionizing radiations; Irradiation; Lung - drug effects; Lung - radiation effects; Lungs; Male; Necrosis; Pentoxifylline - administration & dosage; Pentoxifylline - therapeutic use; Radiation dosage; Radiation Injuries, Experimental - prevention & control; Rats; Rats, Inbred Strains; Short Communications; Skin - drug effects; Skin - radiation effects; Tissues, organs and organisms biophysics
• ISSN: 0033-7587; 1938-5404
• DOI: 10.2307/3577910

Male rats were exposed to single doses (0-30 Gy) of 60 Co γ rays to the right hemithorax. Half of each dose group consumed only control powdered chow after irradiation, and half consumed feed containing 0.10% (w/w) pentoxifylline (50 mg/kg/day). The severity of epilation and desquamation in the field of the radiation port was scored weekly. Two months after irradiation the animals were killed, and pulmonary endothelial function was monitored by the activity of lung angiotensin converting enzyme (ACE) and plasminogen activator (PLA), and by production of prostacyclin ( PGI2) and thromboxane ( TXA2). The amount of hydroxyproline (HP) in the lung served as an index of pulmonary fibrosis. Radiation produced a dose-dependent decrease in ACE and PLA activity in the right lung and an increase in the production of PGI2 and TXA2. This endothelial dysfunction was accompanied by an increase in wet weight and in protein and HP content in the irradiated lung. Pentoxifylline spared only the increase in lung wet weight and protein content, and actually elevated the radiation-induced hyperproduction of PGI2 and TXA2. The severity of the epilation and desquamation reactions increased with increasing radiation dose and time but was independent of diet. These data indicate that pentoxifylline, despite some promising pharmacological actions, has no beneficial effect on acute radiation reactions in rat lung and skin.