Table 1.
Implantation of wild-type blastocysts transferred into pseudopregnant wild-type or COX2−/− mice treated with various agonists
|
Genotype
|
Treatment
|
Day
of sacrifice
|
No. of blastocysts transferred
|
No.
of recipients
|
No. of mice with IS (%)
|
No. of
mice without IS
|
No. of IS
(%)
|
|---|---|---|---|---|---|---|---|
| (+/+) | vehicle | 6 | 112 | 9 | 9 (100) | 0 | 55 (49.1) |
| (+/+) | 8 | 199 | 12 | 12 (100) | 0 | 83 (41.7) | |
| (−/−) | vehicle | 6 | 139 | 10 | 3 (30) | 7a | 7 (5) |
| (−/−) | 8 | 120 | 10 | 3 (30) | 7a | 27 (22.5) | |
| (−/−) | cPGI | 6 | 98 | 6 | 6 (100) | 0 | 32 (32.7) |
| (−/−) | 8 | 99 | 8 | 8 (100) | 0 | 44 (44.4) | |
| (−/−) | cicaprost | 6 | 64 | 4 | 0 (0) | 4a | 0 (0) |
| (−/−) | L-165,041 | 8 | 107 | 7 | 7 (100) | 0 | 43 (40.2) |
| (−/−) | PGE2 | 6 | 98 | 6 | 4 (66.7) | 2 | 16 (16.3) |
| (−/−) | 8 | 57 | 5 | 3 (60) | 2a | 10 (17.5) | |
| (−/−) | L-165,041 + 9-cis-RA | 6 | 95 | 8 | 8 (100) | 0 | 59 (62.1) |
| (−/−) | cPGI + PGE2 | 8 | 124 | 10 | 9 (90) | 1 | 60 (48.4) |
| (−/−) | L-165,041 + PGE2 | 8 | 80 | 6 | 5 (83.3) | 1 | 36 (45) |
Day 4 wild-type blastocysts were transferred into day 4 pseudopregnant uteri of wild-type or COX2−/− recipients. Mice were injected (ip) with the vehicle, cPGI, cicaprost, L-165,041, PGE2, L-165,041 plus 9-cis-RA, cPGI plus PGE2, or L-165,041 plus PGE2 at 1700 hr on the day of blastocyst transfers and each day thereafter until sacrificed. Recipients were examined for implantation sites (IS) on days 6 or 8 by the blue dye method. The doses of various agonists are described in Materials and Methods. Uteri from mice without IS were flushed with saline to recover unimplanted blastocysts. All COX2−/− recipients received progesterone (2 mg/mouse) from day 3 until sacrificed.
A number of delayed blastocysts was recovered from uterine flushings