A
new class of steroid hormone receptors has recently been discovered and those are
the cell membrane receptors (usually steroid hormone receptors are intracellular
receptors, cytoplasmic or nuclear). Membrane steroid receptors are G
protein-coupled receptors (GPR) and an example is GPR30 which binds estrogen. After
estrogen binds to the receptor this pathway activates adenylyl cyclase which produces
cAMP from ATP.
