[Changes of ATPase in fetal rat's cerebral mitochondria and endoplasmic reticulum subsequent intrauterus ischemia and hypoxia].
OBJECTIVE
To investigate the mechanism of intracellular calcium and other ions disturbance by measuring the activity of Ca(2+)-adenosine triphosphatase (Ca(2+)-ATPase) and Na(+)-K(+) adenosine triphosphatase (Na(+)-K(+) ATPase).


METHODS
Model of fetal rats ischemia and reperfusion was established. The duration of ischemia was 15, 30, 45 and 60mins respectively; after ischemia for 15 mins, reperfusion for 1, 4, 8, 15 and 24 hours. There were 7 - 11 fetal rats sacrificed at different time points respectively, 12 rats in sham for control. The mitochondria and endoplasmic reticulium (microsomia) were estracted and the activity of the enzyme was measured.


RESULTS
In the ischemia group: with the development of ischemia, the activity of Ca(2+)-ATPase in mitochondria decreased gradually (P < 0.01), but there was no obvious changes in endoplasmic reticulum. The activity of Na(+)-K(+) ATPase in the two organelles decreased progressively (P < 0.01). While in the reperfusion group: during the 24 hours of reperfusion, the activity of Ca(2+)-ATPase in mitochondria decreased obviously (P < 0.01), but no obvious change in endoplasmic reticulum. Meanwhile Na(+)-K(+) ATPase in this two organelles increased to normal level after reperfusion, but 8 hours later, it decreased for the second time.


CONCLUSIONS
The changes of Ca(2+)-ATPase in mitochondria play an important role in the overload of intracellular Ca(2+) during ischemia and reperfusion, but in endoplasmic reticulium it needs further investigation. Na(+)-K(+) ATPase in the two organelles may be related with their edema.
Song
Weiwei
W
Department of Obstetrics and Gynecology, Second Hospital of China Medical University, Shenyang 110004, China.
Fu
Jianhua
J
Jia
Xianjing
X
Han
Yukun
Y
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000201:enzymology; D005311:Fetal Hypoxia / Q000378:metabolism*; D020925:Hypoxia-Ischemia, Brain / Q000378:metabolism*; D008928:Mitochondria / Q000201:enzymology; D023421:Models, Animal; D051381:Rats; D015424:Reperfusion / Q000379:methods; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*
D000252:Calcium-Transporting ATPases; D000254:Sodium-Potassium-Exchanging ATPase; D002118:Calcium