Serum Immunoglobulin G in the Magnesium-Depleted Rat

Abstract

In a previous communication ( 1 ) , thymic hyperplasia which developed in a significant number of rats depleted of magnesium for 6-12 weeks was described. The hyperplastic glands consisted almost entirely of large cells which morphologically resembled lymphocytes transformed in vitm by antigenic stimulation (2). This observation, together with the requirement of magnesium for protein synthesis, raised the question of the relation of magnesium to the immune status in general and to immunoglobulin synthesis and secretion in particular. The present study was carried out to assess the effect of dietary magnesium depletion on plasma or serum immunoglobulin G (IgG) levels in the rat.Materials and Methods. Animals and diets. Male Sprague-Dawley rats (Sprague-Dawley Farms, Madison, WI), initial mean weight approximately 115 g and aged approximately 35 days, were used in all except one preliminary experiment in which Charles River C.D.2 rats (Charles River Laboratories, Boston, MA) of the same age and sex were used. The animals were housed in individual wire-mesh cages and fed either a magnesium-deficient diet (Diet A ) or a control diet (Diet A + Mg) previously described (1) either ad lib. or by paired feeding as indicated under Results. The duration of experiments ranged from 14 to 88 days. Some animals were repleted with magnesium after 60-77 days of depletion with either subcutaneous or intramuscular injections of 20 mg of magnesium (as 5 % magnesium sulphate in 1Supported by NCI Grant No. 08748 to the Sloan-Kettering Institute. Sprague-Dawley strain. cesarian derived.855 physiological saline) administered over a period of 4 days in each of three experiments (Expts 1, 2, and 3). In Expt 4, two subcutaneous injections of the solution, each containing 10 mg of magnesium, were given 6 hr apart. From the time of the first injection to the termination of experiments, all of these animals were fed the same amount of Diet A + Mg as was consumed by the animals fed Diet A. At time of sacrifice, blood was collected from the dorsal aorta of ether-anesthetized animals into either heparinized syringes or in the absence of anticoagulant. In Expt 4, blood was also collected from the tip of the tail of unanesthetized animals at the commencement of and at various times during the experiment. The thymus of each animal was examined at autopsy, and in experiments of 6 or more weeks duration the gland was removed and weighed. Analytical Methods. Plasma or serum IgG was determined by the method of Fahey and McKelvey ( 3 ) with the following modifications. The antibody-agar gel was prepared in plastic petri dishes after adding 0.5 ml of either lyophilyzed rabbit antiserum to rat IgG reconstituted in sterile distilled water (Miles Laboratories Inc., Kankakee, IL) or rabbit antiserum to rat IgG (Microbiological Associates, Bethesda, MD) to 4.5 ml of 1 % special grade agarose Schwarz/Mann, Orangeburg, NY) in B-1 Beckman barbital buffer, ionic strength 0.025 (Spinco Division, Beckman Instruments, Inc., Palo Alto, CA at 56". Cylindrical wells we...

Reduced Lectin Stimulation of Lymphocytes from Magnesium-Deficient Rats

“…In the present experiments, we found a decrease in the serum proteins, particularly the -globulins (not shown), in agreement with earlier results (5)(6)(7)(8).…”

“…In agreement with the reduced protein biosynthesis, a reduction in immunoglobulins and antibody formation is found during Mg deficiency (5)(6)(7)(8).…”

The Effect of Magnesium Deficiency in Mice on Serum Immunoglobulin Concentrations and Antibody Plaque-Forming Cells

“…sium deficiency, there was a significant decrease in each of the four serum immunoglobulin concentrations ( Table 1). This observation is supported by the recent study of Alcock and Shils with rats in which a 5 4 5 reduction in the serum IgG immunoglobulin concentration occurred after 2 wk of dietary magnesium restriction (9). The changes in immunoglobulin concentrations in the present study are probably not related to large variations in the volume of the intravascular compartment since the IgM immunoglobulin concentration, the only one of the four immunoglobulins limited to the intravascular space, showed a progressive decrease in concentration thereby limiting the possible change in the intravascular space to an expansion (19).…”

Noninvolvement of Histamine and Prostaglandins in the Dermatosis of Magnesium-Deficient Hairless Rats

“…An 'allergic-like dermatosis' was pre viously described during Mg2+ deficiency in mice and rats [Lowenhaupt et al, 1950;Durlach, 1975;Claverie-Benureau et al, 1980;Kruse et al, 1982], In these animals, skin inflammation was associated with numerous immunological disturbances such as eosinophilia [llungerford, 1964;Claverie-Benureau et al, 1980], increased serum IgE levels [Prouvost-Danon et al, 1975], inhibition of antibody production [Battifora, 1971;Augusti et al, 1973;Alcock and Schils, 1974;Elin, 1974: McCoy andKenney, 1974], inhi bition of lymphocyte proliferation [Battifora, 1971] and inhibition of tumor rejection [Mease. 1974], Some authors suggested that the inflam matory process was histamine-dependent [Bois and Beaunes, 1963;Geelen and Van Loghen, 1975].…”