Landolt R, Arn D. Increased radiosensitivity of cerebral capillaries in neonatal Gunn rats as compared to Sprague-Dawley rats.
INTERNATIONAL JOURNAL OF RADIATION BIOLOGY AND RELATED STUDIES IN PHYSICS, CHEMISTRY, AND MEDICINE 1979;
35:529-37. [PMID:
314428 DOI:
10.1080/09553007914550641]
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Abstract
The extent of petechial haemorrhages of the cerebral cortex examined between 14 hours and 4 days after X-irradiation to the head was compared in Sprague-Dawley and homozygous Gunn rats with congenital hyperbilirubinaemia. Animals 1 to 2 days old received single doses of either 250, 500 or 750 rad. By means of a special scoring scale the degree of the damage to the microvasculature was semi-quantitatively estimated. In both strains a significant difference in effect was obtained between 250 and 500 rad, but not between 500 and 750 rad. The shape of the dose-effect curve in Gunn rats was similar to that of Sprague-Dawley rats, but displaced upwards. In Gunn rats the effect of 250 rad was greater than that of 750 rad in Sprague-Dawley rats. Possible radiosensitizing mechanisms are discussed with reference to the literature and our results.
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