Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P56851 (epididymal)
 11,273 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In an attempt to define pathogenesis of the previously described impaired triglyceride (TG) removal in uremia, the effects of the addition of normal and uremic plasma on the activity of lipoprotein lipase (LPL) from rat epididymal adipose tissue were examined. Six uremic patients on chronic dialysis and 13 normals were studied. Adding increments of normal and uremic plasma increased the LPL activity to maximal levels when 0.1 ml of plasma was added. Larger aliquots of uremic plasma produced marked inhibition of LPL activity. This inhibition was not observed with the normal plasma. When increasing amounts of uremic plasma were added to an incubation mixture already maximally activated by 0.1 ml of normal plasma, inhibition of LPL was again observed. This inhibition was still present in uremic plasma which had been dialysed against cold saline. The inhibitor was in the lipoprotein-free (d greater than 1.225) fraction of the plasma. The results indicate that uremic plasma has an LPL inhibitor which is probably a protein and may play a role in the pathogenesis of uremic hypertriglyceridemia.
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PMID:Inhibition of lipoprotein lipase by uremic plasma, a possible cause of hypertriglyceridemia. 118 98

The possible mechanisms of the increase in serum triglycerides (TG) and TG-rich lipoproteins were studied in chronically uremic (U) rats by comparison with either ad-lib fed control (C) rats or diet-restricted (DR), sham-operated pair-fed control rats. A first series of animals was studied in the fed state and a second series after a 16-hr fast. In U animals the concentration of serum TG and TG-rich particles was lower than that of C rats in the fed state but significantly higher than that of C and DR rats after a 16-hr fast. Serum glucose and lactate concentrations in the fed or fasted state were unchanged by uremia. Serum insulin concentration was significantly decreased in U rats as compared to C and DR rats in both series. The fast did not increase the concentration of serum nonesterified fatty acids (NEFA) in U or DR animals to the same extent as in C rats, whereas the serum concentration of beta-hydroxybutyrate (BOB), which was higher than that of C rats in the fed state, was significantly lower after a 16-hr fast. In U animals, as compared to control rats of either series, a significant decrease of epididymal lipoprotein lipase (LPL) activity was observed during both nutritional states when expressing the enzymic activity per number of cells. In conclusion, our data provide evidence against hepatic over-production of TG-rich lipoproteins in rats with chronic renal failure and strongly point to an LPL-mediated defect of their peripheral catabolism, probably related to the insulin deficiency state.
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PMID:Factors of increase in serum triglyceride-rich lipoproteins in uremic rats. 388 97

A model for the study of testicular function in experimental uremia induced by subtotal nephrectomy in mature male rats is described. Glomerular filtration rate was reduced by 87%, resulting in stable uremia for up to 13 weeks with characteristic biochemical changes and reduction in weight of testes, prostate, seminal vesicles, and epididymis but not of heart, liver, spleen, or epididymal fat-pads in comparison with pair-fed and sham-operated, ad libitum-fed littermate controls. Basal serum LH, FSH, and testosterone were reduced and PRL levels increased in chronic uremic rats compared with pair-fed and sham-operated controls. Intratesticular and peripheral venous testosterone levels were reduced by 73-85%, whereas spermatic vein testosterone levels were reduced by 47% suggesting a reduction in blood flow to the uremic rat testis. Sensitivity of uremic Leydig cells to human CG stimulation was normal to increased both in vivo and in vitro without changes in LH receptor affinity or numbers. Fertility was markedly impaired in uremic rats but was restored to normal by either human CG or testosterone treatment. Spermatogenesis was minimally depressed after up to 3 months of uremia. These studies suggest that this experimental paradigm is a suitable model for studying the pathogenesis of early changes in uremic hypogonadism. The predominant early changes of uremic hypogonadism are due to central defects in regulation of pituitary LH secretion with consequent testicular and peripheral hypoandrogenism but initial preservation of spermatogenesis.
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PMID:Testicular function in experimental uremia. 393 Feb 20