“The decrease in bone calcium content induced by PTH or PGE2 was completely inhibited by beta-cryptoxanthin (10(-8)-10(-6) M).”
“The inhibitory effect of beta-cryptoxanthin (10(-7) M) on PTH (10(-7) M)- or PGE2 (10(-5) M)-stimulated decrease in the diaphyseal calcium content was significantly prevented in the presence of 10(-3) M vanadate, an inhibitor of protein tyrosine phosphatase.”