TY - JOUR

T1 - Neutralization of glucagon by antiserum as a tool in glucagon physiology. Lack of depression of basal blood glucose after antiserum treatment in rats

AU - Holst, J J

AU - Galbo, H

AU - Richter, Erik A.

PY - 1978

Y1 - 1978

N2 - The method of producing experimental glucagon deficiency by administration of glucagon antiserum was evaluated in rats. A pool of antisera was prepared, the affinity of which exceeded that of the glucagon receptors of liver cell membranes, whereas the binding capacity of the volume used amounted to more than one-third of the total glucagon content in the rat pancreas. That rapid, extensive, and lasting neutralization of glucagon had taken place after antiserum treatment was indicated by the following findings: When examined more than 1 h after the injection and after 60 min of exercise-stimulated glucagon production, all rats had excess free antibodies in plasma. The concentration of free glucagon was lowered to one-third of the concentration in control rats; at 37 degrees C plasma samples could bind 25% of additional 300 pmol/liter of glucagon in 10 s, and 69% in 120 s; the glycemic response to exogenous glucagon was abolished. Antiserum treatment, however, had no effect on blood glucose in rats fasted for 3 and 10 h, in chemically sympathectomized and adrenomedullectomized rats, and in 48-h-fasted, acutely adrenalectomized rats. The antiserum was found to contain 460 nmol/liter of antibody-bound glucagon, originating in the rabbit in which the antiserum was raised. However, antibody preparations from which the bound glucagon had been effectively removed were equally ineffective in lowering the basal blood glucose in rats, although in three-fourths of the rats the concentration of free glucagon was lowered beyond detection limit. The data indicate that the absolute concentration of glucagon in plasma is of minor importance for the maintenance of basal blood glucose in the rat.

AB - The method of producing experimental glucagon deficiency by administration of glucagon antiserum was evaluated in rats. A pool of antisera was prepared, the affinity of which exceeded that of the glucagon receptors of liver cell membranes, whereas the binding capacity of the volume used amounted to more than one-third of the total glucagon content in the rat pancreas. That rapid, extensive, and lasting neutralization of glucagon had taken place after antiserum treatment was indicated by the following findings: When examined more than 1 h after the injection and after 60 min of exercise-stimulated glucagon production, all rats had excess free antibodies in plasma. The concentration of free glucagon was lowered to one-third of the concentration in control rats; at 37 degrees C plasma samples could bind 25% of additional 300 pmol/liter of glucagon in 10 s, and 69% in 120 s; the glycemic response to exogenous glucagon was abolished. Antiserum treatment, however, had no effect on blood glucose in rats fasted for 3 and 10 h, in chemically sympathectomized and adrenomedullectomized rats, and in 48-h-fasted, acutely adrenalectomized rats. The antiserum was found to contain 460 nmol/liter of antibody-bound glucagon, originating in the rabbit in which the antiserum was raised. However, antibody preparations from which the bound glucagon had been effectively removed were equally ineffective in lowering the basal blood glucose in rats, although in three-fourths of the rats the concentration of free glucagon was lowered beyond detection limit. The data indicate that the absolute concentration of glucagon in plasma is of minor importance for the maintenance of basal blood glucose in the rat.

KW - Animals

KW - Binding Sites, Antibody

KW - Blood Glucose

KW - Glucagon

KW - Immune Sera

KW - Immunization

KW - Kinetics

KW - Male

KW - Neutralization Tests

KW - Physical Exertion

KW - Rats

U2 - 10.1172/JCI109104

DO - 10.1172/JCI109104

M3 - Journal article

C2 - 659632

VL - 62

SP - 182

EP - 190

JO - Journal of Clinical Investigation

JF - Journal of Clinical Investigation

SN - 0021-9738

IS - 1

ER -