title: In vivo and in vitro experiments on relationships between PGA1 and glucose utilization.
abstract: The in vivo and in vitro effects of PGA1 on glucose utilization were investigated in normal rats and in rats with alloxan-diabetes (50 mg/kg i.v. administered 48 hrs before experiment). The animals were divided into two groups. The first group -- which included both normal and diabetic animals -- was submitted to an IVGIT after a 12-h fast and during a sodium chloride infusion. In the second group -- which equally included normal and diabetic rats -- the same GTT was performed during a sodium chloride infusion in which PGA1 had been diluted, so that a dose of 0.5 g/kg/min was administered. This dose is devoid of any effect on cardiovascular activity. For in vitro experiments, glucose utilization was studied in the rat diaphragm incubated with insulin (200 muU/ml) and PGA1 (10 and 100 ng): results demonstrated that PGA1 enhances the insulin effect on glucose utilization and the enhancement is dose-dependent. The same results were observed also in the in vivo experiments: in normal rats PGA1 really improves glucose utilization without any interference with insulin secretion from B-cells. On the other hand, PGA1 has no effect on this utilization in diabetic rats. From our experiments it can therefore be concluded that PGA1 improves glucose utilization, showing a synergic action with the increased quantity of insulin secreted in response to a glucose load. No effect is noted when insulin secretion from B-cells is reduced or absent.
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D003964:Diaphragm / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005947:Glucose / Q000378:metabolism*; D005951:Glucose Tolerance Test; D007328:Insulin / Q000097:blood; D009132:Muscles / Q000378:metabolism*; D011454:Prostaglandins A / Q000494:pharmacology*; D051381:Rats
chemical_list: D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D011454:Prostaglandins A; D005947:Glucose