[Activity and role of tryptase after entrance of amniotic fluid into blood in rats].
OBJECTIVE
To investigate the activity and role of tryptase after entrance of amniotic fluid into blood in rats.


METHODS
Thirty female Wistar rats (20 day pregnancy) were divided into the control group (10, injected with normal saline), amniotic group (10, injected with amniotic fluid), meconium group (10, injected with 1% meconium). After injection, pulmonary tissue was taken out. Tryptase activity was measured by special substrate. The histology of pulmonary tissue was determined by immunohistochemistry (HE).


RESULTS
(1) Dropsy, hemorrhage, and infiltration of neutrophil (PMN), macrophage, leukomonocyte were observed in two experimental groups, but no such changes were found in control group. (2) After injection, tryptase activity in meconium group 176.4 +/- 8.6 and amniotic fluid group 165.4 +/- 7.4 was significantly higher than preexperimental groups 146.8 +/- 8.9 and 147.8 +/- 9.5, respectively (t = 7.58 and t = 4.64, P < 0.01); tryptase activity in control group was 145.3 +/- 10.6 before injection and 146.9 +/- 9.4 after injection, respectively, there was no difference (t = 0.37, P > 0.05). After injection, tryptase activity in meconium and amniotic fluid groups was significantly increased than that in control group (F = 30.66, P < 0.05).


CONCLUSIONS
The activity of tryptase was significantly increased after entrance of amniotic fluid into blood in rats. Degranulation of mast cells to release tryptase may be the important cause of the pathophysiologic change after entrance of amniotic fluid into blood. These results suggest a role for mast cell activation in the mechanism of amniotic fluid embolism. This method is sensitive and effective for diagnosis of amniotic fluid embolism in clinic.
Zhou
Xue-wu
XW
Department of Obstetrics and Gynecology, Second Hospital Affiliated to China Medical University, Shenyang 110004, China.
Shang
Tao
T
Tang
Ying
Y
Tian
Shi
S
Du
Shao-min
SM
Feng
Li-yan
LY
D000653:Amniotic Fluid / Q000378:metabolism; D000818:Animals; D004619:Embolism, Amniotic Fluid / Q000175:diagnosis / Q000378:metabolism*; D005260:Female; D008470:Meconium / Q000378:metabolism; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D053802:Tryptases / Q000378:metabolism* / Q000502:physiology
D053802:Tryptases