The isolation and characterization of growth hormone from anterior lobes of whale pituitaries.

Starting Matinal-The anterior lobes used in these studies were obtained from mature humpback whales.’ The average interval between the death of the animal and removal of the pituitary was about 20 hours. Once removed, the gland was frozen as rapidly as possible and stored at -15” until used. The weights of t,he individual anterior lobes ranged from 6 to 40 gm.; those from females tended to be heavier than those from males. Calcium Hydroxide Extraction and (NHJ $3’04 Fractionation-The preliminary steps employed in the purification of whale somatot,ropin were essentially the same as t,hose previously described by one of us (5) for t,he bovine hormone. In a typical experiment, 178 gm. of frozen anterior lobes of whale pituitaries are ground and stirred for 3 hours at a temperature of 0.5”, with 700 ml. of Ca(OH)z solution of pH 10.0. The suspension is centrifuged, t,he supernatant fluid is saved, and the residue stirred for 1 hour with 550 ml. of Ca(OH)z solution. This suspension is again centrifuged, the residue discarded, and the supernatant fluid combined with that obtained in the previous step. An equal volume of saturated ammonium sulfate solution is now added and the pH of the mixture adjusted to 7.0. The suspension is allowed to stand in the ice box for several hours