REN and osteoporosis: In addition, hypertensive patients have decreased intestinal absorption, increased urinary calcium excretion, and decreased plasma vitamin D concentrations, which promote PTH continuous secretion.[8] Also, sustained elevation of PTH contribute to bone resorption by increasing osteoclast differentiation.[9] Activation of the renin-angiotensin system in hypertensive mice accelerates bone resorption, induces high bone turnover osteoporosis,[10] and it may eventually increase the risk of fragile fractures.