Figure 4.

Blood cell counts and Bleeding assays. (a) Red blood cell counts are reduced in randomly selected 8–12-week-old β3-null mice. Means and standard errors of the means for wild-type, β3-het and β3-null animals are as follows: 8.9 ± 0.15, 9.0 ± 0.16 and 6.0 ± 0.3 (× 10⁶/mm³), a significant difference (P < 0.005) between β3-null and others. (b) Tail bleeding times. β3-null mice all show bleeding times of at least 10 min (at which time bleeding was stopped by cauterization). This was significantly greater than that for either wild-type or β3-heterozygous mice (P < 0.005). (c–f) Localized Shwartzman reactions. Gross hemorrhage in wild-type (c), but not β3-null (d) skin after LPS and TNFα challenge. Histology of blood vessels in the skin after LPS and TNFα challenge in wild-type dermis (e) and β3-null dermis (f).