Effect of low-level basal plus marked "pulsatile"
hyperglycemia on insulin secretion in fetal sheep.
Carver, Thomas D., Susan M. Anderson, Peter W. Aldoretta, William W.
Hay, Jr.
Division of Perinatal Medicine, University of Colorado School of
Medicine, Denver, Colorado 80262, Department of Pediatrics, Madigan
Army Medical Center, Tacoma, Washington 98431-5001
APStracts 3:0111E, 1996.
We compared fetal glucose- and arginine-stimulated insulin secretion
(_I pM) among four groups of pregnant sheep after 10-11 days of
different maternal glycemic patterns: 1) control, euglycemic; 2) low
-level basal plus "pulsatile" hyperglycemic (PHG); 3) markedly
hyperglycemic (HG group); 4) markedly hypoglycemic (LG group). Mean
_I during a hyperglycemic clamp was greatest in the PHG group (190+/
-28 pM, P<0.01) and least in the HG group (64+/-13 pM,
P<0.05) and LG group (68+/-15 pM, P<0.05) compared with the
control group (126+/-18 pM). Following an arginine bolus, was
greater in the PHG group at two of four sampling times over 30
minutes compared with the control group and at all times compared
with the HG and LG groups. The trend in mean _I over the post
-arginine sampling period (PHG 1092+/-114 pM; Control 921+/-86 pM; HG
897+/-117 pM; LG 831+/-57 pM) was in the same direction as for
glucose and was significant (p<0.05). Thus, glucose-stimulated
fetal insulin secretion is regulated by the duration and pattern, as
well as the magnitude, of maternal and fetal hyperglycemia; this
regulation also may extend to insulin-secretion capacity.
Received 4 March 1996; accepted in final form 17 May 1996.
APS Manuscript Number E109-6.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 17 June 96