Stimuli-responding behavior

Examination of the stimulus properties of a large number of phenalkylamines and related derivatives shows many can be characterized as producing either AMPH-like stimulus effects or DOM-like stimulus effects. The structures of some of these agents are shown in figure 1. Certain other agents could not be reliably classified as either AMPH-like or DOM-like because, at the highest dose tested, they either produced vehicle-appropriate (i.e., saline-appropriate) responding or resulted in disruption of behavior. 

An example for stimulus generalization are responses of rats to stress-inducing odors. Laboratoiy rats of the Wistar strain respond to predator odors, specifically mercapto compounds in fox droppings, with stress reactions, for example avoidance behavior such as freezing and increased plasma corticosterone concentrations (Vemet-Mauiy et ah, 1984). The rats were trained to avoid water scented with a mercapto odorant that contained both a keto- and a sulfhydryl group (4-mercapto-4-methyl-2-pentanone). As the animals licked a waterspout, a mild electric shock was applied to their tongue. When different compounds were tested thereafter, the rats avoided compounds with similar... 

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. 

The behavior of the males was used in a bioassay-guided identification of the pheromone, which was extractable by polar solvents such as water or methanol. The bioassay apparatus consisted of a cardboard channel with silk samples treated with different extracts. A positive response consisted of a male producing a typical drumming behavior upon contact with a stimulus. Because males responded to some extent to silk without pheromone, individual spiders were tested first with inactive silk, followed by extract-treated silk (Tichy et al, 2001). GC-MS analyses of the active silk extracts were not successful, even using several derivatization procedures. However, the pheromone structure was deduced by NMR spectroscopy... 

Olfactory-induced behavior of many insects is known to vary as a function of age, experience and/or environmental conditions. Investment in different behavioral repertoires can often be directly correlated to different adaptive patterns older, unmated individuals become more prone to react to a sex-pheromone stimulus, mated females become more motivated to respond to odors emanating from a suitable oviposition site and a hungry insect will more readily respond to food associated odours. 

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