Table 2.
H1RKO-vWFH1R Tg mice are resistant to Bphs
| Strain | Histamine (mg/kg) | No. affected/ Total |
| C57BL/6J | 100 | 4/4 |
| 50 | 4/4 | |
| 25 | 2/2 | |
| 12.5 | 2/2 | |
| H1RKO | 100 | 0/15 |
| H1RKO-vWFH1R Tg | 100 | 0/24 |
Mice were sensitized with 200 ng of purified PTX by i.v. injection on day 0. On day 3, animals were challenged with the indicated doses of histamine (mg/kg) by i.v. injection, and deaths were recorded at 30 min postchallenge. The results are expressed as the number of animals dead divided by the number of animals studied.