Figure 2

Diagram of steroid hormone actions showing that they exert both genomic and nongenomic effects on a variety of cells in the brain and throughout the body. Cell-surface actions of steroids include effects on receptors with ion channels and on receptors coupled to second messengers via G proteins. Question mark denotes uncertainty as to how much intracellular steroid hormones receptors reside in the cytoplasm or in the nucleus in the absence of hormone. In the presence of hormone, these intracellular receptors are found in the cell nuclei where they regulate transcription leading to mRNA production and protein synthesis.

Return to Chapter

published 2000