Globulins Subject

The concentrations of phosphate and glucose were measured on all samples and the urine samples were subject to detailed protein analysis two small proteins, retinol binding globulin and P-2-microglobulin (P2M), received particular attention. Unfortunately, none of the markers alone or in combination proved to be entirely appropriate, but a rising concentration of P2M was able to identify nearly three-quarters of subjects who subsequently showed some degree of renal damage. 

As discussed in detail by Dillard et al. and by Mittman et al. the possible relationship of lysosomal proteases to chronic lung disease has been inferred from the finding of an increased incidence of emphysema in subjects deficient in serum ai>antitrypsin factor, an -globulin that can inhibit lysosomal proteases. (No effect of ozone on serum aj-antitrypsin inhibitor was noted in rabbits chronically exposed to ozone. ) Thus, an ozone-induced increase in concentrations of such enzymes in the lung might produce excess proteolysis and result in eventual chronic lung disease. However, the available evidence is inadequate to support the belief that such a process occurs in humans intermittently exposed to ozone. Further studies of this potential hazard would be of value. 

L4. Lichtman, M. A., Vaughan, J. H., and Hames, G. G., The distribution of serum immunoglobulins, anti G globulins (rheumatoid factors) and anti nuclear antibodies in white and negro subjects in Evans County, Georgia. Arthritis Rheum. 10, 204-215 (1967). 

In the chronic gavage study by NTP (1986), dosed male rats had increased incidences of renal tubular cell hyperplasia, epithelial cell hyperplasia of the renal pelvis, and tubular mineralization. The male rats also had increased incidences of renal tubular cell tumors. The hyperplasia of the tubular cells, therefore, may represent a preneoplastic response (see discussion of cancer below). These proliferative kidney lesions were not observed in male or female mice or in female rats. The mechanism for the induction of proliferative kidney lesions may also be related to a2p-globulin-induced nephropathy (see discussion of cancer below), again raising the question of the relevance of the proliferative kidney lesions in male rats to humans. This issue is presently the subject of scientific investigation. 

Vitamin D and its metabolites circulate in plasma tightly bound to a carrier protein, the vitamin D-binding protein. This -globulin binds 25(OH)D and 24,25(OH)2D with comparable high affinity and vitamin D and l,25(OH)2D with lower affinity. In normal subjects, the terminal half-life of injected calcifediol is 23 days, whereas in anephric subjects it is 42 days. The half-life of 24,25(OH)2D is probably similar. Tracer studies with vitamin D have shown a rapid clearance from the blood. The liver appears to be the principal organ for clearance. Excess vitamin D is stored in adipose tissue. The metabolic clearance of calcitriol in humans indicates a rapid turnover, with a... 

In fact, despite losses of thyroxin-binding globulin in the urine, proportional to total proteinuria and accompanied by the loss of bound T3 and T4, plasma concentrations of T4, T3, and thyroid stimulating hormone (TSH) are usually normal in nephrotic subjects. Sometimes T3 levels may be lowered and T4 levels slightly elevated with increased reverse T3, with normal TSH levels excluding the diagnosis of hypothyroidism. Hypoalbuminemia is to be taken into consideration also in hypothyroid patients on thyroxine substitution therapy. 

Berson SA, Yalow RS (1956) Insulin-I131 metabolism in human subjects Demonstration of insulin binding globulin in the circulation of insulin treated subjects. J Clin Invest 35 170-190... 

This situation is similar to that observed in saliva, where the passage of serum antibodies into the salivary secretion has been demonstrated (E5). When antibodies were present in serum of some healthy subjects, antibodies to various bacteria in saliva were found with hemagglutination and bacterial agglutination tests. The presence of these antibodies in saliva may be correlated with the finding of y-globulin in this secretion (E5). 

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