Dose-Dependent Neuroprotection of Taigabine After 2-Hour Middle Cerebral Artery Embolization in the Rat

The capacity of endothelin-1 to induce severe reductions in cerebral blood flow and ischaemic neuronal damage was assessed in anaesthetised rats. Endothelin-1 (25 μl of 10−7–10−4 M) was applied to the adventitial surface of an exposed middle cerebral artery and striatal blood flow assessed by the hydrogen clearance technique. Endothelin-1 induced severe dose-dependent reductions in cerebral blood flow (e.g., minimum CBF at 10−5 M of 9 ± 11 ml 100 g−1 min−1 compared to 104 ± 22 ml 100 g−1 min−1 with vehicle, p < 0.05), which persisted for at least 60 min at each concentration of endothelin-1. Application of endothelin-1 to the middle cerebral artery produced dose-dependent ischaemic brain damage (e.g., volume of damage of 65 ± 34 mm3 at 10−5 M compared to 0.22 ± 0.57 mm3 for vehicle, p < 0.01). These data demonstrate that endothelin-1 is capable of reducing blood flow to pathologically low levels and provide a new model of controlled focal ischaemia followed by reperfusion.

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The Effect of Chunghyul-Dan on Hyperventilation-Induced Carbon Dioxide Reactivity of the Middle Cerebral Artery in Normal Subjects: A Dose-Dependent Study

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2017/4567217 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9

Author(s):

Chul Jin ◽

Sang-Kwan Moon ◽

Seung-Yeon Cho ◽

Seong-Uk Park ◽

Woo-Sang Jung ◽

...

Keyword(s):

Middle Cerebral Artery ◽

Cerebral Artery ◽

Doppler Sonography ◽

Transcranial Doppler Sonography ◽

Normal Subjects ◽

Healthy Male ◽

Baseline Values ◽

The Mean ◽

Carbon Dioxide Reactivity ◽

Dose Dependent

Background. This study was conducted to show the prompt effect of chunghyul-dan (CHD) on cerebral hemodynamics in order to provide evidence for its use in stroke prevention.Methods. Hyperventilation-induced CO2reactivity of the middle cerebral artery was measured in 12 healthy male volunteers (mean age:26.3±1.1years) using transcranial Doppler sonography. All subjects were examined before and for 3 hours after administration, with an interval of 1 week between measurements.Results. Compared to baseline, the CO2reactivity of the middle cerebral artery increased significantly at 2 and 3 hours after the administration of CHD (600 mg and 1200 mg). The mean blood pressure and heart rate did not vary from the baseline values in all groups.Conclusion. These data suggest that CHD administration (especially 600 mg) immediately improves cerebral blood flow.

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A modified model of reversible middle cerebral artery embolization in rats without craniectomy

Acta Neurochirurgica ◽

10.1007/bf01401114 ◽

1992 ◽

Vol 114 (1-2) ◽

pp. 51-58 ◽

Cited By ~ 4

Author(s):

L. Csiba ◽

D. Bereczki ◽

T. Shima ◽

Y. Okada ◽

K. Yamane ◽

...

Keyword(s):

Middle Cerebral Artery ◽

Cerebral Artery ◽

Artery Embolization ◽

Modified Model

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Inward rectifier potassium channels in the rat middle cerebral artery

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1998.274.2.r541 ◽

1998 ◽

Vol 274 (2) ◽

pp. R541-R547 ◽

Cited By ~ 28

Author(s):

T. David Johnson ◽

Sean P. Marrelli ◽

Marie L. Steenberg ◽

William F. Childres ◽

Robert M. Bryan

Keyword(s):

Middle Cerebral Artery ◽

Cerebral Artery ◽

Inward Rectifier ◽

Selective Inhibitors ◽

Nitric Oxide Synthase Inhibitor ◽

Inward Rectifier Potassium Channels ◽

Synthase Inhibitor ◽

Resting Tone ◽

Oxide Synthase ◽

Dose Dependent

Inward rectifier K+ channels (Kirs) were studied in the isolated perfused rat middle cerebral artery (MCA). The addition of 15 mM K+ (KCl) to the extraluminal bath dilated the MCAs. These dilations were blocked by selective inhibitors for the Kirs (40 μM BaCl2 or 40 mM CsCl) but not selective inhibitors for other K+channels (glibenclamide, tetraethylammonium, or 4-aminopyridine). Neither removal of the endothelium nor treatment with the nitric oxide synthase inhibitor ( N G-nitro-l-arginine methyl ester, 10 μM) affected the K+-induced dilation. The addition of BaCl2 to resting MCAs produced a dose-dependent constriction of 8–12%, indicating that, during resting conditions, Kirs aid in setting or determining the resting tone. The magnitude of the dilations produced by the addition of K+ or constrictions produced by BaCl2 were independent of pressure over a range of 40–100 mmHg. We conclude that Kirs, which produce a dilation when activated, exist on the vascular smooth muscle of the rat MCA. These Kirs aid in determining the resting tone of the vessel, and their function is independent of pressure over physiological pressure ranges.

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An ultrastructural analysis of the sympathetic innervation of the rabbit ear artery and middle cerebral artery and their branches

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100125075 ◽

1992 ◽

Vol 50 (1) ◽

pp. 934-935

Author(s):

John T. Dodge ◽

John A. Bevan

Keyword(s):

Middle Cerebral Artery ◽

Cerebral Artery ◽

Sympathetic Innervation ◽

Electrical Field Stimulation ◽

Rabbit Ear Artery ◽

Electrical Field ◽

Functional Differences ◽

Ear Artery ◽

Rabbit Ear ◽

Vascular Beds

Unlike many peripheral vascular beds, the sympathetic nervous system exerts little control on cerebral blood flow. The contractile response of isolated rabbit middle cerebral artery (MCA) segments to electrical field stimulation of its intramural nerves is less than in a similar-sized artery from the ear. This study was undertaken to characterize and compare the perivascular neuromuscular relationships and innervation density of similar-sized arteries varying in diameter from these two different regional arterial beds to see if there were structural correlates for these functional differences.

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