At the same time, it stimulates production of calcitriol which promotes absorption of calcium in the small intestine, while also increases reabsorption in the kidney.
Lastly, parathyroid hormone increases calcium reabsorption and reduces the reabsorption of phosphate from the kidneys, so more phosphate is excreted through the urine.
T3 increases cardiac output, stimulates bone reabsorption thinning out the bones and then activates the sympathetic nervous system, the part of the nervous system responsible for our fight-or-flight response.