Further Studies on the Fractionation of Human Pituitary Glands1

Abstract

A detailed biological analysis and a simplified procedure for a method of serial extraction of acetone-preserved human pituitary glands is described. FSH (follicle stimulating hormone) is found almost exclusively in the 1st extract (at a mean potency of 2.1 X NIH-FSH-S1), together with a substantial amount of LH (luteinzing hormone) (0.13 X NIH-LH-S1) and some TSH (thyroid stimulating hormone). A 2nd extraction under different conditions, yields GH (growth hormone), primarily in one fraction, at a potency approximately equivalent to the USP (bovine) Standard, together with prolactin. Also present in the second extract is LH (0.35 X NIH-LH-S1), and the greater part of the TSH. The 3rd extraction yields additional GH, prolactin and ACTH. However, the recovery of ACTH is low. The method yields satisfactory amounts of GH, at a stage of purity suitable for use in the human, and recovers virtually all the FSH, LH and TSH, in forms readily susceptible to further purification. A modification and significant improvement of the bioassay procedure for GH, by body weight gain in immature hypophysectomized rats, is also described.