Abstract | STUDY HYPOTHESIS: We attempted to determine whether the reduced egress of mRNA from brain nuclei following in vivo ischemia and reperfusion is caused by direct damage to the nuclear pore-associated NTPase that impairs the system for nuclear export of polyadenylated, or poly(A)+, mRNA. DESIGN: Prospective animal study. INTERVENTIONS:
NTPase activity and poly(A)+ mRNA transport were studied in nuclear envelope vesicles (NEVs) prepared from canine parietal cortex isolated after 20 minutes of ischemia or 20 minutes of ischemia and 2 or 6 hours of reperfusion. RESULTS: Brain NEV NTPase Michaelis-Menten constant (Km) and maximum uptake velocity (Vmax) and the ATP-stimulated poly(A)+ mRNA egress rates were not significantly affected by ischemia and reperfusion. In vitro exposure of the NEVs to the OH. radical-generating system completely abolished NTPase activity. CONCLUSION: We conclude that brain ischemia and reperfusion do not induce direct inhibition of nucleocytoplasmic transport of poly(A)+ mRNA. This suggests that the nuclear membrane is not exposed to significant concentrations of OH. radical during reperfusion.
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Authors | B R Tiffany, B C White, G S Krause |
Journal | Annals of emergency medicine
(Ann Emerg Med)
Vol. 25
Issue 6
Pg. 809-17
(Jun 1995)
ISSN: 0196-0644 [Print] United States |
PMID | 7755206
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Review)
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Chemical References |
- RNA, Messenger
- Hydroxyl Radical
- Acid Anhydride Hydrolases
- Nucleoside-Triphosphatase
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Topics |
- Acid Anhydride Hydrolases
(pharmacokinetics)
- Animals
- Biological Transport
- Brain Ischemia
(metabolism)
- Dogs
- Heart Arrest
(metabolism)
- Hydroxyl Radical
(metabolism)
- Nuclear Envelope
(metabolism)
- Nucleoside-Triphosphatase
- Prospective Studies
- RNA, Messenger
(metabolism)
- Reperfusion
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