Decrease of non-suppressible insulin-like activity after pancreatectomy and normalization by insulin therapy.

Non-suppressible insulin-like activity (NSILA-S) was determined in 5 dogs before and after pancreatectomy and again during insulin therapy. All NSILA-S determinations were carried out on serum samples which were passed over Sephadex G-50 columns equilibrated with 1 M acetic acid. The levels of NSILA-S decreased drastically shortly after pancreatectomy and rose slowly after institution of insulin therapy, to normal levels. During the period of severe diabetes after pancreatectomy the concentration of growth hormone was elevated. These findings indicate that 1) the pancreas cannot be the site of synthesis and release of NSILA-S, 2) NSILA-S levels do not always parallel growth hormone levels and 3) the synthesis and secretion of NSILA-S among other factors is under the control of insulin.