ABSTRACT
I. Introduction................................................................................. 233 II. Corticosterone Rapidly and Potently Inhibits Courtship
Behavior in
Taricha
...................................................................... 234 III. Membrane Corticosteroid Receptors in
Taricha
........................ 235 IV. Functional Studies of the Membrane Corticosterone
Receptor ....................................................................................... 236 V. Biochemical Studies of the Membrane Corticosterone
Receptor in
Taricha
...................................................................... 236 VI. Membrane Corticosterone Receptor Binding Site
Recognizes Kappa-Selective Ligands ........................................ 237 VII. Convergence of Corticosteroid and Opioid Pathways ............ 238
VIII. Concluding Remarks .................................................................. 239 References ............................................................................................. 239
In vertebrates from primitive fishes to humans, harsh stimuli trigger stress responses that activate a common set of hormones. The most important stress hormones include CRH, ACTH, corticosteroids (especially corticosterone and cortisol), catecholamines (especially epinephrine), vasopressin (or the non-mammalian homologue vasotocin), and opioid peptides (especially
β
- endorphin, dynorphin, and orphanin FQ). As this list suggests, stress
responses are complex physiological events, frequently involving corticosteroid and opioid pathways.