The process of DHT binding to androgen receptors involves several steps:
Synthesis of DHT: Testosterone, a male sex hormone, is converted into DHT through the action of the enzyme 5-alpha-reductase. This conversion occurs in various tissues, including the prostate, skin, and hair follicles.
Transport in the bloodstream: DHT circulates in the bloodstream, carried by proteins like albumin and sex hormone-binding globulin (SHBG).
Diffusion into target cells: DHT can diffuse across the cell membrane and enter the cytoplasm of target cells.
Binding to androgen receptors: Inside the cell, DHT binds to androgen receptors, which are proteins located in the cytoplasm or nucleus. These receptors are present in target tissues such as the prostate, skin, and hair follicles.
Formation of hormone-receptor complex: Once DHT binds to the androgen receptor, a hormone-receptor complex is formed.
Translocation to the nucleus: The hormone-receptor complex translocates to the cell nucleus. In the nucleus, the complex acts as a transcription factor, influencing the transcription (gene expression) of specific target genes.
Gene expression and cellular response: The binding of DHT to androgen receptors leads to the activation or repression of specific genes, resulting in changes in cellular function and response. For example, in the case of hair follicles, DHT binding to androgen receptors can contribute to the miniaturization of hair follicles, leading to hair loss in individuals genetically predisposed to androgenetic alopecia (male pattern baldness).