Changes in the spontaneous action potentials from the whole, isolated, intact bovine pituitary gland following an injection of various bovine pituitary intraglandular colloid fractions.

Bovine pituitary intraglandular colloid (IGC) of intermediate lobe (IL) origin with accessions from the anterior lobe (AL), can modify the spontaneous action potentials (SAP) from AL, IL and posterior lobe (PL) cells. It was discovered that intraglandular colloid contains peptides ACTH, alpha-MSH, and beta-LPH when subjected to a series of radioimmunoassays. These peptides are thought, in part, to be responsible for altering the SAP.