Diabetes, Vol 34, Issue 9 870-875, Copyright © 1985 by American Diabetes Association
Plasma pancreatic polypeptide response to insulin-induced hypoglycemia as a marker for defective glucose counterregulation in insulin-dependent diabetes mellitus
NH White, RL Gingerich, LA Levandoski, PE Cryer and JV Santiago
Defective glucose counterregulation occurs in some insulin-dependent
diabetic subjects (IDDMs) as a result of a combined deficiency of glucagon
(IRG) and epinephrine (EPI) secretion in response to insulin-induced
hypoglycemia. To determine whether the deficient glucagon response, the
deficient epinephrine response, or both are manifestations of autonomic
dysfunction, we used the pancreatic polypeptide (PP) secretory response to
insulin-induced hypoglycemia as a marker for autonomic neuropathy. Seven
nondiabetic controls and 21 IDDMs were given insulin at 40 mU/kg/h after
overnight euglycemia. Eight of the IDDMs had defective counterregulation
(-CR), and 13 had adequate counterregulation (+CR) by our previously
published criteria. Those with -CR had a blunted EPI (delta EPI = 102 +/-
16 pg/ml; mean +/- SEM) and PP (delta PP = 12 +/- 13 pg/ml) response as
compared with controls (delta EPI = 310 +/- 49; delta PP = 498 +/- 43) and
IDDMs with +CR (delta EPI = 291 +/- 32; delta PP = 521 +/- 86). In
controls, IRG rose by 31 +/- 6 pg/ml; in IDDMs, IRG failed to rise
significantly above baseline regardless of counterregulatory status.
Although the PP and EPI responses correlated well (r = 0.626, P less than
0.001), the IRG response failed to correlate with either the EPI or the PP
response. We conclude that the deficient epinephrine, but not glucagon,
secretory response to hypoglycemia in diabetic subjects is a result of
autonomic neuropathy.(ABSTRACT TRUNCATED AT 250 WORDS)