Changes in plasma glucose, insulin, glucagon, catecholamine, and glycogen contents in tissues during development of alloxan diabetes mellitus in rats.

Alloxan monohydrate (ALX) was given to rats (20 mg/100 g body weight) and plasma glucose (PG), immunoreactive insulin (IRI), immunoreactive glucagon (IRG), and catecholamine (CA) as well as the glycogen (G) content in the liver, muscle, and kidneys were measured. Although whether hypoglycemia was present immediately after injection was not clear, the PG level increased, with a modest peak after 2 h. The PG levels in rats receiving food 6 h after ALX injection increased substantially after 1 h and continued to increase after 24 h.

The role of insulin-sensitive phosphodiesterase in insulin action.

The physiological role of the insulin-sensitive phosphodiesterase in mediating the antilipolytic actions of insulin was investigated in rat fat cells with two phosphodiesterase inhibitors, namely, 3-isobutyl-1-methylxanthine (IBMX) and griseolic acid. Insulin activates the phosphodiesterase when incubated with intact fat cells and blocks isoproterenol-induced cellular cAMP production and lipolysis, in a time- and dose-dependent manner. High concentrations of IBMX (1 mM), but not lower concentrations (0.

A pilot clinical trial of a new oral hypoglycemic agent, CS-045, in patients with non-insulin dependent diabetes mellitus.

CS-045, (+/-)-5-[4-(6-hydroxy-2,5,7,8-tetramkethylchroman-2- ylmethoxy)benzyl]-2,4-thiazolidinedione, lowers plasma glucose in several animal models of non-insulin dependent diabetes mellitus (NIDDM) presumably by increasing insulin sensitivity. Little adverse effect was found in a phase 1 study on healthy male subjects. In order to test its efficacy in lowering plasma glucose in NIDDM in man, a pilot multi-center clinical trial of CS-045 was carried out in 146 patients with NIDDM whose glycemic control was inadequate (FPG greater than 140 mg/dl) on diet and/or other oral hypoglycemic agents.

Glucagon inhibits insulin activation of glucose transport in rat adipocytes mainly through a postbinding process.

Incubation of rat adipocytes with 1 microM glucagon plus adenosine deaminase (5 micrograms/ml) inhibited maximally insulin-stimulated 3-O-methyl-D-glucose (MeGlc) transport by approximately 70%, concomitant with 30% and 55% decreases in insulin binding and cellular ATP, respectively. In contrast, under conditions where cellular ATP levels are well preserved (i.e.