Hormone Signaling Through cAMP and Calcium

Water-soluble hormones signal through cell receptors and second messengers. Because these hormones cannot cross the plasma membrane, they bind to protein receptors that span the membrane and start signaling inside the cell. The response often depends on small messenger molecules such as cAMP or calcium ions.

Water-soluble hormones cannot move across the plasma membrane, so they use protein receptors that span the membrane to trigger intracellular signaling pathways.

These pathways activate second messengers inside the cell, including cAMP or calcium ions.

Many hormones bind to transmembrane G protein-coupled receptors that link to regu...