Amphibian Pituitary Growth Hormone and Prolactin: Immunochemical Relatedness to Rat Growth Hormone
Ted Hayashida 1,
Paul Licht 2, and
Charles S. Nicoll 3
1 Department of Anatomy and Hormone Research Laboratory, University of California, San Francisco 94122
2 Department of Zoology, University of California, Berkeley 94720
3 Department of Physiology-Anatomy, University of California, Berkeley 94720
Growth hormone and prolactin were electrophoretically isolated from amphibian pituitaries and then were tested in a radioimmunoassay with labeled rat growth hormone and antiserum to the same hormone. This isolation and purification of the hormones increased the steepness of the slopes of competitive inhibition in this system when compared to those of crude extracts. Both hormones from most species tested showed high immunochemical cross-reactivity, indicating that amphibian growth hormone and prolactin are structurally related to rat growth hormone.
