lecture 3 (copy)

What is a xenobiotic?

Any chemical deemed foreign to the body.

What is xenobiotic metabolism?

It is the biochemical process through which xenobiotics are metabolized.

Why do we need xenobiotic metabolism(2)?

Enhances the elimination of foreign substances.

Detoxifies a system.

What are xenobiotic metabolizing enzymes?

Enzymes involved in xenobiotic metabolism

Phase 1 (oxidation) in xenobiotic metabolism

Converts substances to more water-soluble forms.

Phase 2 (conjugation) in xenobiotic metabolism

Further modifies substances for incorporation into urine or bile.

Where do xenobiotic metabolizing enzymes occur(4)?

Liver

Lungs

Small and large intestines

nasal mucosa

What does first-pass metabolism undergo?

Hepatic biotransformation

What does first-pass metabolism refer to?

Orally administered drugs in the epithelial cells of the small intestine

What are genetically determined variations in xenobiotic metabolism?

Differences in metabolism due to genetic factors.

What genetic factors are influenced?

Enzyme Activity

Drug efficacy and safety