β-THROMBOGLOBULIN IN URINE WITH SPECIAL REFERENCE TO THE RELATIONSHIP TO PLATELET-LIKE BODIES IN URINE

Abstract

It has been reported that in healthy people and in patients with various diseases, platelets and/or cell elements originating from platelets are always discharged in the urine: these small bodies were termed “platelet-like bodies in the urine” (U-PLB). The authors have assessed a platelet-specific protein β-thromboglobulin (β-T. G.) in urine, and have investigated their relationship to the U-PLB, the urinary components and the renal functions.
The average values of β-T. G. in the urinary supernatant and the non-sonicated and the sonicated sediment of healthy adult control were 0.577ng/ml, 0.410ng/ml and 0.70ng/ml, respectively. In 2 cases suffering from so-called idiopathic renal bleeding (I. R. B.) and one case with acute glomerulonephritis, the supernatant β-T. G. contents were 2.77ng/ml, 4.35ng/ml, and 2.08ng/ml, respectively. The sediment β-T. G. contents in each of these 3 cases exceeded 11ng/ml. In 3 cases with chronic glomerulonephritis (C. G. N.), the values of the sediment β-T. G. content were higher than those of the supernatant β-T. G. content, and in 2 cases out of these 3 cases, the sonicated sediment β-T. G. was higher than that in non-sonicated materials. In other cases with C. G. N., the sediment β-T. G. revealed a lower value than the supernatant β-T. G.. It has also been reported that β-T. G. is contained in the α-granules of platelets. From electron micrographic findings, many U-PLB in I. R. B. can be concluded to present platelets. However, the U-PLB in glomerulonephritis vary from platelet-like bodies to cell elements originating from platelets, and those in healthy individuals resemble cell elements originating from platelets. Moreover, the U-PLB in I. R. B. react with various reagents.
In 4 cases with hypertension and one case with idiopathic edema, the values of the supernatant β-T. G. content were higher than those of the sediment β-T. G. content.
The β-T. G. is always discharged in urine. The relationship of the urinary supernatant β-T. G. content and the sediment β-T. G. content to the osmolarity, creatinine, urea nitrogen, natrium, potassium and calcium in the urine and the creatinine-clearance was different. From these results, it is also suggested that the U-PLB is involved in urine. The β-T. G. in urine is mainly secreted as the β-T. G. itself and sometimes excreted as the β-T. G. non-released in the U-PLB. And, it is suggested that the β-T. G. excretion into urine is related with the renal functions and the renal pathologic changes.