title: In vivo detection of fluctuating brain steroid levels in zebra finches.
abstract: This protocol describes a method for the in vivo measurement of steroid hormones in brain circuits of the zebra finch. A guide cannula is surgically implanted into the skull, microdilysate is collected through a microdialysis probe that is inserted into the cannula, and steroid concentrations in the microdialysate are determined using the enzyme-linked immunosorbent assay (ELISA). In some cases, the steroids measured are derived locally (e.g., neural estrogens in males), whereas in other cases, the steroids measured reflect systemic circulating levels and/or central conversion (e.g., the primary androgen testosterone and the primary glucocorticoid corticosterone). A reverse-microdialysis ("retrodialysis") method that can be used to deliver pharmacological agents into the brain to influence local steroid neurochemistry as well as behavior is also discussed.
authors.affiliation: Neuroscience and Behavior Program, Center for Neuroendocrine Studies, University of Massachusetts, Amherst, Massachusetts 01003; Molecular and Cellular Biology Program, University of Massachusetts, Amherst, Massachusetts 01003.
authors.forename: Maaya
authors.initials: M
authors.lastname: Ikeda
authors.affiliation: Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, California 90095;
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Rensel
authors.affiliation: Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, California 90095;
authors.forename: Barney A
authors.initials: BA
authors.lastname: Schlinger
authors.affiliation: Neuroscience and Behavior Program, Center for Neuroendocrine Studies, University of Massachusetts, Amherst, Massachusetts 01003; Molecular and Cellular Biology Program, University of Massachusetts, Amherst, Massachusetts 01003.
authors.forename: Luke
authors.initials: L
authors.lastname: Remage-Healey
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism* / Q000601:surgery; D004797:Enzyme-Linked Immunosorbent Assay; D046369:Finches / Q000378:metabolism*; D008297:Male; D017551:Microdialysis / Q000379:methods*; D013256:Steroids / Q000378:metabolism*
chemical_list: D013256:Steroids