Distribution of dissociation constant values of muscarinic agonists

The frequency distributions of dissociation constant values of some muscarinic agonists (carbachol, muscarone and cis-2-methyl-5-trimethylammoniummethyl-1,3-oxathiolane) obtained on guinea-pig ileum and atria and rat urinary bladder have been examined to see if the means of the dissociation constant values and the statistical tests for their significance, should be based on geometric rather than on arithmetic means. For the three compounds the distributions on a logarithmic scale did not significantly deviate from normality while the distributions on an arithmetic scale tended to deviate from normality.