Modification of Late Radiation Damage in the Rectum of Rats by Deproteinized Calf Blood Serum (ActoHorm) and Pentoxifylline (PTX)

Purpose: Prevention and treatment of radiation-induced late rectal ulcer using deproteinized calf blood serum (ActoHorm) or pentoxifylline.

Materials And Methods: Rectal ulcers were induced in Wistar rats using single X-ray doses of 20, 22 and 24 Gy. ActoHorm or pentoxifylline were given at various times after irradiation. The induced rectal damage was assessed by clinical examination, rectoscopy and histology of the post-mortem specimens.

Results: Neither ActoHorm nor pentoxifylline affected the incidence or latency or had any pronounced effect on healing of late rectal ulcers. Histological examination showed increased regenerative activity of the mucosal epithelium in all ActoHorm treated animals.

Conclusion: Neither ActoHorm nor pentoxifylline prevented the development of radiation-induced rectal ulcers. The stimulation of mucosal epithelium with ActoHorm might, however, be effective in healing of superficial erosions of the intestinal mucosa.