Induced Defense Model

Table 7.1 Published studies explicitly testing hypotheses derived from the Induced Defense Model, a corollary model to the Optimal Defense Model, concerning variation in the concentration of secondary metabolites or resistance to herbivores in different macroalgal species... 

Lively, C.M., Developmental strategies in spatially variable environments barnacle shell dimorphism and strategic models of selection, in The Ecology and Evolution of Inducible Defenses, Tollrian, R. and Harvell, C.D., Eds., Princeton University Press, Princeton, NJ, 1999, 245. 

Lymphocyte proliferation and cytokine production form the basis of progression to an immunocompetent response, and drug-induced alterations in either or both parameters can indicate a potential for impaired host defense or selftolerance. Furthermore, ex vivo functional assays have the potential to elucidate mechanisms of drug-induced immunotoxicity and may provide essential information to address human risk (i.e., relevant host defense models). Finally, state-of-the-art methodologies enable rapid, highly sensitive and comprehensive evaluations of leukocyte activity, and implementation in preclinical evaluations may assist in the identification and/or characterization of drug-induced immunotoxicity. 

Lorentz was the first to consider such problems for a reasonably defensible model of induced dipoles derive the local Lorentz field j and from this obtain the venerable Clausius Mossotti (or perhaps more properly Lorentz-Lorenz) formula. As shown schematically in Figure 1 (a) the molecules are assumed to be at sites on a cubic lattice with uniform macroscopic along the z axis. 

The ideal animal model for any human chnical condition must fulfill three criteria (McKinney and Bunney 1969) (1) pharmacological treatments known to be effective in patients should induce comparable effects in the animal model (predictive validity) (2) the responses or symptoms observed in patients should be the same in the animal model (face validity) (3) the imderlying rationale should be the same in both humans and animal models (construct validity). In other words, the ideal animal model for anxiety has to respond to treatment with anxiolytics such as benzodiazepines with reduced anxiety it has to display defense behavior when confronted with a threatening stimulus the mechanisms underlying anxiety as well as the psychological causes must be identical. 

---