Abstract | BACKGROUND AND PURPOSE:
Subarachnoid hemorrhage frequently leads to a long-term cerebral artery narrowing called vasospasm. Recently, the involvement of myosin light chain kinase has been found in experimental vasospasm in our laboratory. We therefore measured the activity of serine/ threonine protein phosphatases 1 and 2A in the rabbit basilar artery in vasospasm and in vasocontraction to study their role, particularly in regard to vasospasm compared with vasocontraction. METHODS: RESULTS: Values of mean activity of protein phosphatase 1 in myofibrillar extract were 3.58 +/- 0.26 nmol/min per milligram in the control group, 3.22 +/- 0.12 nmol/min per milligram in the spastic group on day 2, and 3.01 +/- 0.16 nmol/min per milligram in the spastic group on day 4 (a significant decrease in protein phosphatase 1 activity in the spastic group on days 2 and 4). In contrast, these values did not show any significant changes in the KCl and serotonin groups. Values of mean activity of protein phosphatase 2A in cytosolic extract were 0.90 +/- 0.07 nmol/min per milligram in the control group, 0.75 +/- 0.10 nmol/min per milligram in the spastic group on day 2, and 0.62 +/- 0.17 nmol/min per milligram in the spastic group on day 4 (a significant reduction in protein phosphatase 2A in the spastic group on days 2 and 4). There was no evidence of significant changes of protein phosphatase 2A in cytosolic extract in the KCl and serotonin groups. CONCLUSIONS:
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Authors | M Fukami, E Tani, A Takai, I Yamaura, N Minami |
Journal | Stroke
(Stroke)
Vol. 26
Issue 12
Pg. 2321-7
(Dec 1995)
ISSN: 0039-2499 [Print] United States |
PMID | 7491658
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Serotonin Receptor Agonists
- Serotonin
- Potassium Chloride
- Phosphoprotein Phosphatases
- Protein Phosphatase 1
- Protein Phosphatase 2
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Topics |
- Animals
- Basilar Artery
(enzymology, physiopathology)
- Ischemic Attack, Transient
(enzymology, physiopathology)
- Muscle Contraction
(drug effects)
- Muscle, Smooth, Vascular
(enzymology, physiopathology)
- Phosphoprotein Phosphatases
(metabolism)
- Potassium Chloride
(pharmacology)
- Protein Phosphatase 1
- Protein Phosphatase 2
- Rabbits
- Serotonin
(pharmacology)
- Serotonin Receptor Agonists
(pharmacology)
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