247MilmJIn, A.E., J.A. RusseU: Some effects of purified growth hormone on carbohydrate metabolism in the rat. Endocrinology 47: 114 (1950) Park, C.R., D.H. Brown, M. Comblath, W.H. Daughaday, M.E. Krahl: The effect of growth hormone on glucose up-take by the isolated rat diaphragrn. J. biol Chern. 197: 151 (1952) Sehaleh, D.S., D.M. Kipnis: Abnormalities in carbohydrate tolerance associated with elevated nonesterified fatty acids. SummaryW,e studied the effect of hyperthyroidism on the insulin response to hyperglycemia in the dog during a standard oral (OGm and intravenous (lVGTn glucose tolerance test. The development of the hyperthyroid condition was elicited through chronic subcutaneous I-thyroxin treatment at one of the following doses: 0.5 and 100"1 Ikg body weightl day, for 10-12 days. Blood sugar and serum immunoreactive insulin (IR!) were measuredNormal fasting blood sugar and serum IRI levels remained unchanged in the dog, despite the thyroxin treatment. The rate of disappearance of intravenously injected glucose from blood was normal as weil However, a shorter tban normal, 50% diminished and late insulin response to glucose was found in the hyperthyroid group (both thyroxin levels).The blood sugar eurve during the OGTT was found to be normal during the mild degree of hyperthyroidism, which was accompanied with an earlier tban normal and moderately rnaintained insulin response to hyperglycemia, whose maximum was 25% above normal The blood sugar curve during the OGrr was normal in the severely hyperthyroid dogs only for the 60 minute-period following glucose administration. However, the blood sugar was still above controllevels 30 minutes later in this group. A definitely reduced (low,late and shorter than normal) insulin response to hyperglycemia was found after thyroxin treatment (high level), Horm. Metab. Res. 3: 247-251 (1971) K e y -W 0 r d s: Hyperthyroid Dog -Serum Immunoreaclive Insulin -Oral Glucose Tolerance Test -Intravenous Glucose Tolerance Test

No abstract

The effect of hyperthyroidism on BS, serum IRI and FFA basally and during a GIT was studied in anesthetized dogs. They were given a glucose priming~ose (rapid, intravenouit injection) immediately foUowed by an intravenous glucose infusion for one hour. In hyPerthyroid dogs under anesthesia, the basal BS and serum IRI levels were normal, but the serum FFA levels above those of the normals also under anesthesia. During the GIT the BS levels foUowed those of the normals only over the first 30 min; thereafter, the glucose levels fell less than in the normals. In normal dogs, a biphasic insulin response to glucose was observed; aserum IRI peak at 10 min and a plateau between 30 and 75 min were found. The insulin response of hyperthyroid dogs was less than in the normals throughout the GIT, while they showed no initial peak of response. Circulating FF A values were low in normal dogs, remained unaffected by glucose administration and failed to rebound as hyPerglycemia declined. In the hyperthyroid condition, serum FFA levels fell abruptly during and excessively rebounded after the maintained hyperglycemia. We conclude that, in the dog, hyperthyroidism depresses the ability of tissues to take up !arge amounts of glucose from circulation, and impairs the insulin response to glucose, particularly the immediate response.

The purpose of this study was to determine the effect of thiopentone anaesthesia on glucose metabolism. Blood sugar (BS), serum immunoreactive insulin (IRI) and serum non-esterified fatty acid (NEFA) concentrations were measured during the course of (I) an intravenous glucose tolerance test (IVGTT), and (2) an intravenous insulin test (ITT), in conscious and

The effect of T therapy (T 0.5 and T 10) on BS, serum IRI and FFA levels of thyroidectomized dogs during an OGTT was studied.Either T dose failed to res tore the BS profiles in these animals: T 10 corrected the delayed onset of hyperglycemia after glucose load but it definitely raised the BS baseline; T 0.5 also enhanced this baseline and, also, reduced the magnitude of hyperglycemia.Both T doses reduced the overnormal serum IRI levels observed in the thyroidectomized dogs both in the post-absorptive condition and during the test; T 10 was more effective than T 0.5; normal serum IRI levels, however, were not achieved during the test.T therapy only partially corrected the serum FF A profiles of the thyroidectomized dogs. Both T 0.5 and T 10 restored both serum FF A baseline and return to baseline at the end of the test, but they overshot to overnormal serum FFA values du ring the fall early after glucose load.