Structure, mechanism of action and biological role of steroidogenic factor-1 (SF-1), in particu- lar the significance of this factor for the normal function of the adrenal cortex, have been presented. SF-1 is a transcription factor, classified to an orphan nuclear receptor family, which interacts with the specific nucleotide sequence within promoters of the target genes, including those encoding proteins participating in the synthesis or transport of steroid hormones or their precursors in the cell.

The extracellular concentration of protons is much higher than intracellular its level. Responsi- ble for generation and maintaining this difference is the proton pump (H+) present in the outer cell membrane. A proton pump uses ATP as a substrate and expels H+ from the cell; consequently, the ions are asymmetrically located and the electrochemical gradient appears, which is used in many physiological processes such as cellular growth, osmoregulation and transport of substances into the cell.