What question did this study set out to answer?

To examine how the vascular endothelium and tissue levels of cyclic GMP modulate the antagonistic mechanism of prazosin against noradrenaline in rat aorta.

November 1, 1986British Journal of PharmacologyOpen Access

Role of cyclic GMP in the modulation by endothelium of the adrenolytic action of prazosin in the rat isolated aorta

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Authors

IAIyad J. AlosachieSpecialty Materials (United States)TGThéophile GodfraindUCLouvain

Discussion

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Implication

Ex vivo study demonstrates that endothelial cyclic GMP alters prazosin antagonism in rat aorta, indicating tissue messenger levels control agonist efficacy.

Key Points

To examine how the vascular endothelium and tissue levels of cyclic GMP modulate the antagonistic mechanism of prazosin against noradrenaline in rat aorta.
Assessed noradrenaline concentration-response curves and prazosin antagonism in isolated rat aortic rings with intact versus removed endothelium.
Manipulated cyclic GMP levels using methylene blue to reduce cyclic GMP and 8-bromo-cyclic GMP to elevate cyclic GMP.
Determined noradrenaline receptor affinity and efficacy by estimating receptor reserve in the presence and absence of endothelium.
Prazosin acted as a non-competitive antagonist in intact endothelium preparations, but exhibited competitive antagonism at 0.3 nM to 10 nM in endothelium-denuded tissues.
Methylene blue converted prazosin to a competitive antagonist in intact tissues, whereas 8-bromo-cyclic GMP induced non-competitive antagonism in endothelium-denuded tissues.
Noradrenaline receptor affinity remained identical between intact and denuded tissues, but agonist efficacy and receptor reserve were lower in the presence of intact endothelium.

Cite This Study

Alosachie et al. (1986) studied this question.

synapsesocial.com/papers/6a845913e7eedc1abc68bb1a https://doi.org/10.1111/j.1476-5381.1986.tb11152.x

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Implication

Ex vivo study demonstrates that endothelial cyclic GMP alters prazosin antagonism in rat aorta, indicating tissue messenger levels control agonist efficacy.

Role of cyclic GMP in the modulation by endothelium of the adrenolytic action of prazosin in the rat isolated aorta

Discussion

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Implication

Key Points

Cite This Study

Role of cyclic GMP in the modulation by endothelium of the adrenolytic action of prazosin in the rat isolated aorta

Discussion

Member takes

Implication

Key Points

Cite This Study

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