Localized hyperthermia and X-irradiation of murine jejunum in situ: a new method.
In C3H mice, preparative surgery apposed a 15 mm length of jejunum to the peritoneal surface of the ventral abdominal wall. After the mice healed, manipulation of the abdominal wall made possible selective hyperthermic treatment and X-irradiation of the immobilized jejunal segment (IJS) while it remained within the peritoneal cavity and in continuity with the rest of the intestines. For hyperthermia, the ventral abdominal wall and attached IJS was flattened between two aluminium plates immersed in a standard water bath. The temperature at the mesenteric attachment of the IJS was within 0.5 degrees C of a 44 degrees C bath 100 s after immersion and within 0.3 degrees C at steady-state. Xenon-133 washout studies showed that the treatment technique did not compromise blood flow to the IJS. The preparative surgery left the IJS normally responsive to X-irradiation as determined by crypt microcolony assay. Hyperthermia treatment by itself at 44 degrees C for up to 20 min caused no loss of crypts or villi; however, adjuvant 5-15 min 44 degrees C hyperthermia displaced the X-ray crypt-survival curves towards lower doses without changing their slopes. Nevertheless, formal statistical analyses admitted both additive and multiplicative interpretations of the effects of X-irradiation and adjuvant hyperthermia on intestinal crypt survival. After adjuvant hyperthermia, the surviving crypts were preferentially clustered near the mesenteric attachment to a greater extent than was expected from the asymmetry of the heat dose.
D000818:Animals; D002470:Cell Survival / Q000528:radiation effects; D005260:Female; D005336:Fiber Optic Technology; D006979:Hyperthermia, Induced / Q000379:methods*; D007583:Jejunum / Q000473:pathology / Q000528:radiation effects / Q000601:surgery; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D011878:Radiotherapy / Q000379:methods*; D011879:Radiotherapy Dosage; D013821:Thermometers; D014964:X-Ray Therapy / Q000379:methods*; D014980:Xenon Radioisotopes
D014980:Xenon Radioisotopes