Bisphosphonates Flashcards
Mechanism of bisphosphonates and when we use them
They bind to bone and inhibit osteoclast-mediated bone resorption, and indirectly stimulate osteoblast activity
We use these for osteoporosis, hypercalcemia and metastatic bone disease
Problems with bisphosphonates
GI distress and bone pain
Examples of bisphosphonates
Alendronate and anything else that ends in dronate
Teriparatide mechanisms and what we use it for
This guy acts a little differently than the bisphosphonates. This one promotes bone formation by stimulating the differentiation of osteoblasts. By doing this, it increases bone mineral density
It also stimulates Ca2+ absorption in the renal distal convoluted tubules and the release of calcium from bone through a G-protein couples receptor.
These qualities make Teriparatide great for osteoporosis.
What do we use Selective Estrogen Receptor Modulators for and how do they work?
We use these for osteoporosis prevention and for breast cancer.
They work by activating estrogen receptos in bone and the heart while antagonizing those in the uterus and mammary tissue.
Raloxifene
A SERM used for osteoporosis mostly that does not stimulate the endometrium, thus reducing postmenopausal bone resorption
Tamoxifen
This one is great for breast cancer because it is an antagonist to breast estrogen receptors and also agonist to bone to help with osteoporosis.
However, it is an agonist for the uterus so we have an increased risk of endometrial cancer.
Denosumab
Human monoclonal antibody that binds to RANKL to stop it from binding RANK, therefore reducing osteoclast differentiation.
How does Calcitonin work?
Calcitonin inhibits bone resorption, leading to decreased blood calcium and phosphate.
It also binds to osteoclast receptors and inhibits their actions.
It acts on the kidneys to stop resorption of calcium and phosphate in the proximal tubules.
