12-19-2005, 05:08 AM
12>Two normal, healthy subjects volunteer for a study on insulin secretion
. In Patient 1, blood glucose is increased to 150 mg/dL by direct intravenous
infusion. In Patient 2, blood glucose is increased to 150 mg/dL by ingestio
n of oral glucose. The peak plasma insulin concentration produced in Patient
1 is 70 mU/mL while in Patient 2, it is 95 mU/mL. Which of the following
best explains the higher insulin concentration in Patient 2?
A. Ingested glucose activates a sympathetic reflex that increases b cell release of insulin
B. Ingested glucose increases duodenal secretion of gastric inhibitory peptide (GIP), increasing b cell release of insulin
C. Intravenous glucose increases islet cell secretion of somatostatin, inhibiting b cell release of insulin
D. Intravenous glucose increases islet cell secretion of glucagon, inhibiting b cell release of insulin
. In Patient 1, blood glucose is increased to 150 mg/dL by direct intravenous
infusion. In Patient 2, blood glucose is increased to 150 mg/dL by ingestio
n of oral glucose. The peak plasma insulin concentration produced in Patient
1 is 70 mU/mL while in Patient 2, it is 95 mU/mL. Which of the following
best explains the higher insulin concentration in Patient 2?
A. Ingested glucose activates a sympathetic reflex that increases b cell release of insulin
B. Ingested glucose increases duodenal secretion of gastric inhibitory peptide (GIP), increasing b cell release of insulin
C. Intravenous glucose increases islet cell secretion of somatostatin, inhibiting b cell release of insulin
D. Intravenous glucose increases islet cell secretion of glucagon, inhibiting b cell release of insulin