Parathyroid hormone binding to epithelium of the human lens

Cell homogenates from human lens epithelium express in binding site for Parathyroid hormone. Kinetic data reveal an affinity/dissociation constant to Kd 17.5 x 10(-11) M and a maximal binding of Bmax 15 x 10(11) M. These data are comparable to previously tested tissues as lymphocytes or renal plasma membranes. No differences can be observed for the association characteristics between senile and juvenile lenticular epithelial cells.