Abstract:
:To understand whether the NO-dependent vasodilator L-arginine was effective upon a chronically hypertensive cerebral capillary endothelium, dynamic susceptibility contrast MRI was used to measure the relative cerebral blood volume (rCBV) changes in nonischemic spontaneously hypertensive rats (SHRs). rCBV was measured in 11 rats at 4.7 T using fast gradient echo imaging with intravenous injection of Gd-DTPA. Images were acquired before, immediately after, and up to 90 min after the infusion of 300 mg/kg L-arginine (n = 7) or of an equivalent volume of saline (n = 4). L-arginine increased rCBV in cortex beginning 10 min after infusion and reached significance after 30 min (P < 0.01), reached a peak of 1.24 +/- 0.06 (mean +/- SEM) times pre-injection level after 50 min, and was sustained throughout the 90 min observation period. In contrast, the rCBV in the deeper gray matter (striatum) showed no statistically significant change over the 90 min observation period. While this is consistent with previous studies showing that L-arginine infusion can directly modulate vascular tone and cerebral hemodynamics, it demonstrates that the effect is present only in cortex, and that it can occur also in the setting of a disturbed capillary endothelium.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Caramia F,Yoshida T,Hamberg LM,Huang Z,Hunter G,Wanke I,Zaharchuk G,Moskowitz MA,Rosen BRdoi
10.1002/mrm.1910390123subject
Has Abstractpub_date
1998-01-01 00:00:00pages
160-3issue
1eissn
0740-3194issn
1522-2594journal_volume
39pub_type
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更新日期:2004-03-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1993-05-01 00:00:00
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