Loss of a single ahr allele does not affect systolic or diastolic blood pressure or heart rate, while loss of both alleles results in significantly decreased systolic and diastolic blood pressure. (A) Systolic, diastolic and pulse arterial blood pressure, (B) heart rate, and (C) hourly mean arterial pressure over a 24 hr period of male ahr+/+, ahr+/− and ahr−/− mice as measured by radiotelemetry (n=8–10/genotype). Data represent mean ± SEM and were analyzed by one-way ANOVA, *p < 0.05, compared to ahr+/+; †p < 0.05 compared to ahr+/− (A and B), or by repeated measures two-way ANOVA, using post hoc Holm-Sidak comparisons; *p < 0.05, compared to both ahr+/+ and ahr+/−.