The purpose of this chapter is to describe steroid hydroxylations catalyzed by cytochrome P-450. Steroid hormones are hydroxylated in the liver by a microsomal mixed-function oxidase system. This process precedes excretion of steroids in bile and urine and serves to inactivate the hormones and make them more water soluble. In some cases, hydroxylation of steroid hormones in the liver may also result in biologically active metabolites with specific physiological functions. The reason that steroid hormones are natural substrates for the microsomal cytochrome P-450-dependent enzyme systems, they offer certain advantages in biochemical studies on liver microsomal cytochrome P-450. In conclusion, the use of steroid hormones as substrates in experimental work involving liver microsomal cytochrome P-450 is encouraged owing to the unique possibilities to obtain detailed and clear information on catalytic specificity of cytochrome P-450 preparations.
ASJC Scopus subject areas
- Molecular Biology