TOX 300 Lecture Notes - Lecture 11: Polycyclic Aromatic Hydrocarbon, Aryl Hydrocarbon Receptor, Polychlorinated Biphenyl
Document Summary
Receptors strict definition: cellular proteins that normally serve as receptors for endogenous ligands (e. g. hormones, neurotransmitters, cytokines) Broader definition: enzymes, transport proteins, nucleic acids, structural proteins, membrane lipids (cid:894)(cid:454)e(cid:374)o(cid:271)ioti(cid:272) (cid:862)targets(cid:863)(cid:895) Many xenobiotics cause their effects ( or ) by interacting w/ receptors. Differe(cid:374)t t(cid:455)pes of effe(cid:272)t depe(cid:374)d o(cid:374) (cid:449)hat the re(cid:272)eptor"s role is i(cid:374) the (cid:271)od(cid:455) a(cid:374)d (cid:449)here it is in the body. If the receptor is global (e. g. cholinergic and adrenergic receptors), it will cause a widespread effect when it is targeted. If the receptor is only in a specific organ, the effect will be restricted to that organ. Structure-activity relationships (sar) = the affinity of a xenobiotic for a receptor depends on its chemical structure (stereochemistry) the (cid:862)lo(cid:272)k a(cid:374)d ke(cid:455)(cid:863) (cid:373)odel. Endogenous ligands have a specific 3d structure that allows them to be recognized by their receptors and cause an effect. **ahr binds to pcbs (polychlorinated bipehnyls) and pahs (polycyclic aromatic hydrocarbons)
