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. 1974 Jun;51(2):287–300. doi: 10.1111/j.1476-5381.1974.tb09659.x

On the simultaneous action of two competitive antagonists

BL Ginsborg, RP Stephenson
PMCID: PMC1776755  PMID: 4451745

Abstract

1 A hypothesis is outlined predicting the conditions in which the addition of a second competitive antagonist will increase rather than reduce the response to an agonist.

2 Experiments were performed with the guinea-pig ileum as the test tissue, hexyltrimethyl ammonium as the agonist, benzilyltropine methiodide as the `slow' antagonist and pentyltriethyl ammonium as the `fast' antagonist.

3 The results are consistent with the hypothesis, if the affinity constant for hexyltrimethyl ammonium is between 2.7 and 3.7 × 104 M-1, if the dissociation time constant for the slow antagonist is greater than 10 min and if that for the fast antagonist is less than 10 seconds.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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