Plasma-insulin activity in normal subjects estimation of the normal plasma as means of comparison in the isolated rat diaphragm test

SUMMARY The uptake of glucose by isolated rat diaphragm is increased in vitro by serum from normal oxen and diabetic patients treated with ox insulin; by slower moving albumin, β- and γ-globulin fractions of serum from normal oxen; by slower moving albumin, α2-, β- and γ-globulin fractions of serum from treated diabetics (prepared by zone electrophoresis on columns of treated cellulose). More rapidly moving albumins from both types of serum did not stimulate glucose uptake. The effect of serum or protein fractions of serum was absent or markedly reduced in the presence of antiserum to ox insulin prepared in guinea-pigs. It is concluded that the stimulating effect of serum and protein fractions of serum on uptake of glucose by diaphragm is due to circulating insulin. The effect of insulin on uptake of glucose by diaphragm is shown to be potentiated by the presence of corticotrophin, prolactin, normal guinea-pig serum and an albumin preparation from the serum of hypophysectomized rats. The significance of these results in relation to the detection and assay of insulin in blood with isolated diaphragm and to the transport of insulin in blood is discussed.

Download Full-text

PLASMA-INSULIN ACTIVITY IN DIABETES MELLITUS MEASURED BY THE RAT DIAPHRAGM TECHNIQUE

The Lancet ◽

10.1016/s0140-6736(55)92583-6 ◽

1955 ◽

Vol 266 (6890) ◽

pp. 583-587 ◽

Cited By ~ 103

Author(s):

J. Vallance-Owen ◽

Barbara Hurlock ◽

N.W. Please

Keyword(s):

Diabetes Mellitus ◽

Plasma Insulin ◽

Rat Diaphragm ◽

Insulin Activity

Download Full-text

THE INSULIN ACTIVITY OF BOVINE AND OVINE BLOOD PLASMA

Journal of Endocrinology ◽

10.1677/joe.0.0250043 ◽

1962 ◽

Vol 25 (1) ◽

pp. 43-52 ◽

Cited By ~ 9

Author(s):

N. F. CUNNINGHAM

Keyword(s):

Blood Plasma ◽

Plasma Insulin ◽

Plasma Glucose Level ◽

Extraction Procedure ◽

Rat Diaphragm ◽

Pregnant Sheep ◽

Insulin Activity ◽

Plasma Insulin Levels ◽

Pregnancy Toxaemia

SUMMARY The acid—ethanol extraction procedure described by Baird & Bornstein (1957) has been shown to extract from bovine and ovine blood plasma material having an insulin-like action in vitro in the rat diaphragm assay. The amounts of insulin activity extracted from plasma of non-pregnant cows and sheep generally indicated plasma insulin levels of from 100–500 μu./ml. plasma. Plasma insulin activity did not appear to be related to plasma glucose level in these animals. Insulin activities of 100 μu./ml. plasma, or less, were found in two cows soon after parturition, in some pregnant sheep bearing twins round about the time of parturition, in four acetonaemic cows and in three of six sheep with pregnancy toxaemia.

Download Full-text

SENSITIVITY OF THE RAT DIAPHRAGM TO GROWTH HORMONE.

Acta Endocrinologica ◽

10.1530/acta.0.0540645 ◽

1967 ◽

Vol 54 (4) ◽

pp. 645-662 ◽

Cited By ~ 8

Author(s):

Å. Hjalmarson ◽

K. Ahrén

Keyword(s):

Growth Hormone ◽

Inhibitory Effect ◽

Rat Diaphragm ◽

Intracellular Accumulation ◽

Slight Effect ◽

Kidney Capsule ◽

Muscle Tissues ◽

Hypophysectomized Rats ◽

Isolated Rat

ABSTRACT The effect of growth hormone (GH) in vitro on the rate of intracellular accumulation of the non-utilizable amino acid α-aminoisobutyric acid (AIB) was studied in the intact rat diaphragm preparation. Bovine or ovine GH (25 μg/ml incubation medium) markedly stimulated the accumulation of AIB-14C by diaphragms from hypophysectomized rats, while there was no or only a very slight effect on diaphragms from normal rats. In diaphragms from rats with the pituitary gland autotransplanted to the kidney capsule GH in vitro stimulated the accumulation of AIB-14C significantly more than in diaphragms from normal rats but significantly less than in diaphragms from hypophysectomized rats. Injections of GH intramuscularly for 4 days to hypophysectomized rats made the diaphragms from these rats less sensitive or completely insensitive to GH in vitro. These results indicate strongly that the relative insensitivity to GH in vitro of diaphragms from normal rats is due to the fact that the muscle tissues from these rats has been exposed to the endogenously secreted GH. The results show that GH can influence the accumulation of AIB-14C in the isolated rat diaphragm in two different ways giving an acute or »stimulatory« effect and a late or »inhibitory« effect, and that it seems to be a time-relationship between these two effects of the hormone.

Download Full-text