[The effect of maternal hyperglycemia on insulin secretion by monolayer-cultured B cells of neonatal rats--a perifusion study].
To evaluate the effect of maternal hyperglycemia on insulin secretion by neonatal rat B cells, perifusion was conducted on monolayer cultures of rat neonates from normoglycemic (C) mothers or those made slightly (SH) and highly (HH) hyperglycemic by the injection of streptozotocin. In the C, SH and HH groups, B cells responded to 16.7 mM glucose, 10 mM leucine, 10 mM 2-ketoisocaproate and 10 mM arginine in a biphasic manner, although these nutrients provided stimuli so feeble that insulin secretion in the second phase was slightly raised above basal levels. However, quantitative relationships differed. Compared with the C group, B cells in the SH group showed a significant increase in the secretion of the second phase in response to glucose, 2-ketoisocaproate and arginine but not to leucine, whereas there was no difference in the secretion of the first phase between these two groups. In the HH group, a lower insulin secretion of the first and second phase was observed. These results are compatible with hyperglycemia-hyperinsulinaemia theory concerning the function of B cells in neonates born to slightly hyperglycemic mothers and with a defect in insulin secretion by neonates from highly hyperglycemic females.
Takao
F
F
Department of Hygiene, Hyogo College of Medicine, Nishinomiya, Japan.
D000818:Animals; D000831:Animals, Newborn; D001120:Arginine / Q000494:pharmacology; D002478:Cells, Cultured; D005260:Female; D005947:Glucose / Q000494:pharmacology; D006943:Hyperglycemia / Q000139:chemically induced / Q000378:metabolism*; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000378:metabolism*; D007651:Keto Acids / Q000494:pharmacology; D007930:Leucine / Q000494:pharmacology; D010477:Perfusion; D011247:Pregnancy; D011248:Pregnancy Complications / Q000139:chemically induced / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013311:Streptozocin
D007328:Insulin; D007651:Keto Acids; D013311:Streptozocin; C013082:alpha-ketoisocaproic acid; D001120:Arginine; D007930:Leucine; D005947:Glucose