The glucose fatty-acid cycle. Its role in insulin sensitivity and the metabolic disturbances of diabetes mellitus.

Metabolism of isolated fat cells. i. effects of hormones on glucose metabolism and lipolysis.

Fatty acid binding to plasma albumin.

The present studies were undertaken to assess the mechanisms responsible for cortisol-induced insulin resistance in man The insulin dose-response characteristics for suppression of glucose production and stimulation of glucose utilization and their relationship to monocyte and erythrocyte insulin receptor binding were determined in six normal volunteers after 24-h infusion of cortisol and 24-h infusion of saline The infusion of cortisol (2 /µg kg-1 min-1) increased the plasma cortisol concentration approximately 4-fold (37 ± 3 us 14 ± 1 µg/dl; P < 001) to values observed during moderately severe stress in man This hypercortisolemia increased postabsorptive plasma glucose (126 ± 2 us 97 ± 2 mg/dl; P < 001) and plasma insulin (16 ± 2 us 10 ± 2 µU/ml; P < 001) concentrations and rates of glucose production (24 ± 01 us 21 ± –01 mg kg-1 min-1; P < 001) and utilization (25 ± 01 us 21 ± 01 mg kg-1 min-1; P < 001) Insulin dose-response curves for both suppression of glucose production (half-

Cortisol-Induced Insulin Resistance in Man: Impaired Suppression of Glucose Production and Stimulation of Glucose Utilization due to a Postreceptor Defect of Insulin Action

Brown adipose tissue providing internal heating jacket and metabolic heater overlying systemic vasculature, noting cold survival role

Brown fat and thermogenesis.

SummaryEpinephrine and norepinephrine stimulate production of nonesterified fatty acids from rat adipose tissue when incubated in vitro in rat plasma, presumably by stimulating the hydrolysis of ne...

A lipolytic action of epinephrine and norepinephrine on rat adipose tissue in vitro.

Some Hormonal Influences on Fat Mobilization from Adipose Tissue

Contrasting requirements for the lipolytic action of corticotropin and epinephrine on adipose tissue in vitro.

The influence of epinephrine and fasting on adipose tissue content and release of free fatty acids in obese-hyperglycemic and lean mice

Publisher Summary Until recently, the concept has been firmly entrenched that the tropic hormones are devoid of action on tissues other than their respective target glands. From time to time in the past, extra-adrenal actions have been attributed to adrenocorticotropin (ACTH), but usually they were either discounted by the demonstration of an active contaminant in the hormone preparation used or were dismissed on the grounds that they were due to a contaminant which had not been detected. While ACTH has been isolated from the adenohypophysis, purified, and characterized as a polypeptide consistsing of 39 amino acids, it, has not been proved that the hormone which is secreted to act on the adrenal cortex has the same structure as the active peptide prepared chemically. Indeed, several investigators have suggested that there is a corticotropin precursor. This problem is not unique for ACTH, as is apparent from the recent claim that the physical properties of both circulating as well as extractable insulin in the pancreas are quite different from those of crystalline or partially purified insulin. Most hormones are now recognized as existing in the blood in forms bound to proteins. These must be dissociated before they become biologically active. In this chapter, the present status of the extra-adrenal actions of ACTH is reviewed. Consideration is given not only to those which seem well established, but also to others which are questionable, either because of uncertainty concerning the purity of the hormone or the techniques used, but which deserve to be reinvestigated by more reliable methods. Implications concerning the relationship of the structure of ACTH and its functions arise from the studies of extra-adrenal actions and are discussed.

Frank L. Engel

Papers

A lipolytic action of epinephrine and norepinephrine on rat adipose tissue in vitro.

Some Hormonal Influences on Fat Mobilization from Adipose Tissue

Contrasting requirements for the lipolytic action of corticotropin and epinephrine on adipose tissue in vitro.

The influence of epinephrine and fasting on adipose tissue content and release of free fatty acids in obese-hyperglycemic and lean mice

Extra-adrenal Actions of Adrenocorticotropin