Dose-response plots

Thresholds may also be determined by extrapolation of dose-response plots. In this approach, the perceived odor intensity is measured at several... 

Fig. 27 Dose-response plots for /V-bcnzoyloxy-A-benzyloxybcnzamide 28a in 5. typhimurium TA100 (a) comparison of activity with and without S9 and (b) linear plots without S9.

Another important kinetic parameter usually determined is the value of IC50, defined as the half maximal inhibitory concentration that provides an indication of the potency of an inhibitor under certain the specific conditions of an evaluation. This parameter is typically determined from dose-response plots in which the percentage conversation or inhibition is plotted against the logarithmic concentration of inhibitor employed in each evaluation. The parallel nature of the /.tPLC system described in this chapter is ideal for the evaluation of this parameter. 

FIGURE 6.50 Dose-response plots obtained for H-89 inhibitor. (Adapted from Wu, J. et al., Assay Drug Dev. Technol., 4, 653, 2006.)... 

FIGURE 10.3. Dose-response plotted in terms of the probit plot of cumulative percentage response to logarithm of exposure duration. 

Figure 19.8. Dose-response plot showing functional differences between partial and full agonist. These data illustrate that two compounds of similar potency may differ in functional efficacy. In this case, the full agonist causes the same degree of stimulation as does the endogenous ligand. Conversely, the partial agonist, although of similar potency, is only partially efficacious. These data are modified from actual published studies from the authors laboratory (Brewster et al. J. Med. Chem. 330 1756-1764, 1990).

Figure 14. Log dose-response plot for 3-methyIcholanthrene Induced carcinogenesis. (Reproduced with permission from Ref. 13.)...

Figure 2-2. Quantai dose-response plots from a study of the therapeutic and lethal effects of a new drug in mice. Shaded boxes (and the accompanying curves) indicate the frequency distribution of doses of drug required to produce a specified effect, ie, the percentage of animals that required a particular dose to exhibit the effect. The open boxes (and corresponding curves) indicate the cumulative frequency distribution of responses, which are log-normaiiy distributed. (Reproduced, with permission, from Katzung BG [editor] Basic Clinical Pharmacology, 8th ed. McGraw-Hill, 2001.)...

The resolution by dosage of the two lonophore responses is clearly apparent in the dose-response plot of Figure 8. Coronary flow rises progressively until it plateaus at 10-50 yg/kg monensin. Higher doses cause a secondary increase in flow reflecting the rise in atrial pressure which drives blood through the coronaries. Only 2.5 yg/kg (i.e. 2.5 ppb) are suffucient to double the basal flow rate. It is possible to detect the increased flow of 1 yg/kg (1 ppb) with statistical confidence. 

The dose-response plot (Figure 2.11) is one of the most important relationships in toxicology. Such a plot can be prepared by dosing a uniform population of test subjects with increasing levels of toxicant and observing response, usually death. For such a curve, the dose corresponding statistically to the death of 50% of the test subjects is denoted as the LD50. Most commonly, toxicities of substances... 

FIGURE 2.11 A dose-response plot of percentage of a uniform population of subjects responding in a specified way (most commonly death) versns log dose. The dose at which statistically half of the subjects die is designated as the LD50. 

---