Detailed definition
Estrogen receptor beta (ERβ), encoded by the ESR2 gene, is the second principal nuclear estrogen receptor. Compared to ERα, ERβ is more highly expressed in central nervous system, ovarian granulosa cells, lung, GI tract, and vascular endothelium. ERβ activation often opposes ERα-driven proliferation, and ERβ-selective ligands have been studied for menopausal symptoms and breast cancer prevention. The neuroprotective and mood-related effects of estrogen appear to involve ERβ substantially. The differing tissue distributions of ERα and ERβ explain why some SERMs and ER-selective ligands have tissue-specific effects.
Why it matters in menopause
Understanding that estrogen acts through two receptors with different distributions and effects is part of why blanket statements like "estrogen causes cancer" or "estrogen is dangerous" are oversimplifications. The same hormone produces different effects in different tissues depending on receptor balance.
Related terms
Sources
External references: Wikipedia.