Sex-related factors in acute carbon monoxide intoxication in one strain of mice.

In the OF1 mouse strain, males are less resistant than females to acute carbon monoxide intoxication. Castration of males increases their resistance to carbon monoxide. For Neonates injected with four different doses of testosterone (20-500 mg per kg) or oestradiol (2-50 mg per kg), more effect on resistance to carbon monoxide in the (adult) mice was found for oestradiol than for testosterone. Pregnancy decreases resistance to carbon monoxide intoxication. Experiments performed with males and females of different ages, in various societal conditions, show the effects of sex-related dimorphism and aggressiveness. The sex-related difference in carbon monoxide resistance is not modified by a previous hypoxic stress (nitrogen hypoxia, carbon monoxide intoxication, sodium cyanide injection) but is suppressed when the CO intoxication is carried out at a low ambient temperature (13 degrees C).