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This is where we will explain our animal models and why we use them in particular.
Anolis carolinensis (the green anole)
Anoles are uniquely suited to studying stress. Mechanisms of variability among individual neural and endocrine stress responses are the focus of our laboratory and the reason for choosing Anolis. There are differing reactions to stress among individuals of any species, but in A. carolinensis these differences are visible by means of a postorbital patch of skin which darkens. We are interested in elucidating the mechanisms by which experience modulates the responsiveness of neural and hormonal stress responses, and the eyspot gives us a visible marker for the timing of these events. These studies include measuring behaviorally stimulated changes in biogenic amines by HPLC using microdialysis and brain punch microdissection, using social aggression and dominance to stimulate neuroendocrine stress responses. This is meaningful because the eyespot provides predictive information on different responsiveness and social outcome. That is, the winner of an aggressive interactions during the establishment of dominance is foretold by the celerity of eyespot darkening: Winners/dominant males have darkening first. This reliable chromatic change makes Anolis carolinensis especially well suited to study differences in neuroendocrine responsiveness between individuals. Anoles are also interesting with respect to the relationships between stress, biological rhythms, and reproduction.
Eleutherodactylus coqui
This frog is a directly developing amphibian. As such, it is different from most other frogs which have a larval, or tadpole, stage, but similar to most other vertebrates. Because direct development has evolved recently in this taxon, coqui are a useful comparison for neural development with metamorphosing species.
Onchorhyncus mykiss (rainbow trout)
Like anoles, salmonid fishes are excellent models for testing the roles of neuroendocrine factors on social stress, and vice versa.
Pimephales promelas
The fathead minnow is a useful model for studying the toxic effects of ammonia on central monoamines. Other animal models may employ some type of hepatic failure or shunt, which may confound the effects of ammonia on monoamines. Ammonia is a major concern for aquaculture and it appears that monomines can serve as a biomarker because they are depeleted in a concentration dependent manner. Further studies on a larger scale with other fish species will determine if this will be a useful marker.
Rat
This is the most well studied, and best understood neurobiological model. Much of our comparative work using other models is compared to the rat.