Why does first aid say "PTS stimulates osteoblasts directly, but osteoclasts indirectly." If PTH increases resporption of Ca and Phos, shouldn't it only affect osteoclasts?
Why does first aid say "PTS stimulates osteoblasts directly, but osteoclasts indirectly." If PTH increases resporption of Ca and Phos, shouldn't it only affect osteoclasts?
no, there is no receptor for PTH on oseoclasts, but there is one on osteoblasts, upon binding osteoblasts secrete M-CSF and RANK-L, which stimulate osteoclasts to break down bone.