Effects of Extracellular Calcium and of Calcium Antagonists on the Contractile Responses of Isolated Human Pial and Mesenteric Arteries

@article{Brandt1981EffectsOE,
  title={Effects of Extracellular Calcium and of Calcium Antagonists on the Contractile Responses of Isolated Human Pial and Mesenteric Arteries},
  author={Lennart Brandt and Karl Erik Andersson and Lars Edvinsson and Bengt Ljunggren},
  journal={Journal of Cerebral Blood Flow \& Metabolism},
  year={1981},
  volume={1},
  pages={339 - 347}
}
In isolated human pial arteries (diameter 0.4–0.5 mm), contractions were produced by potassium, noradrenaline, serotonin, and prostaglandin F2α. For comparison, experiments were also performed on human mesenteric arteries. Threshold concentration for potassium-induced contraction in pial arteries was about 10 mm; in mesenteric arteries it was 3–5 mm higher. In pial arteries the calcium antagonists nifedipine and nimodipine caused an almost complete relaxation of contractions induced by… 

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