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A Mainero

Publications and source records attributed to A Mainero.

6 recordsLinked to original sources
PubMed1994

Copper and zinc metabolism in aminonucleoside-induced nephrotic syndrome.

Copper (Cu) and zinc (Zn) were measured in urine, serum and tissues from rats with nephrotic syndrome (NS) induced with a single subcutaneous dose of puromycin aminonucleoside (PAN; 15 mg/100 g BW). Control animals were pair-fed. Urine was collected daily, and the rats were sacrificed on day 10. PAN-nephrotic rats had proteinuria (days 3-10), high urinary Cu (days 1, 2, 4-10) and Zn (days 3-10) excretion. On day 10, nephrotic rats had: (a) albuminuria, hypoalbuminemia, hypoproteinemia, high urine and low serum levels of ceruloplasmin; (b) low Cu and Zn serum levels; (c) high clearance and fractional excretion of Cu and Zn, and (d) low kidney and liver Cu content and essentially normal tissue Zn levels. The alterations in Cu metabolism were more intense than those in Zn metabolism. Urine Cu and Zn showed a positive correlation with urine total protein on days 3-10 which suggests that high urinary excretion of Cu and Zn may be due to the excretion of its carrier proteins. In conclusion, these rats did not show a typical Zn deficiency but a clear decrease in Cu in the liver and kidney.

Animals↗
PubMed1992

A study of erythropoiesis and iron metabolism in the rabbit in vivo. II. Dependence of the response on iron storage and transport.

Rabbits subjected to a daily bloodletting schedule of 10 ml blood per kg body weight increase four- or fivefold their erythropoietic production compared to normal non-bled animals. The maximum response they can reach under these conditions mobilizes more than 9 mg of iron per day per rabbit into hemoglobin. When fed ad libitum with their regular diet, they do not need any further iron supplement for full erythropoiesis. The experimental increment in iron body stores and/or serum iron levels does not enhance their erythropoietic response, demonstrating that iron is not rate limiting under the conditions studied. Furthermore, although serum iron levels are elevated onefold in the controls under chronic anemia with respect to non-bled animals, the concentration of serum transferrin is only slightly increased; hence, the iron saturation of this protein changes from a 50% to an 80% level. In the absence of an extra supplement of iron, rabbits subjected to chronic bloodletting show no signs of body iron depletion, as judged by their continuous macrocytic RBC production.

Anemia↗
PubMed1992

Serum and urinary ceruloplasmin in experimental nephrotic syndrome.

The levels of ceruloplasmin (Cp) and total protein were measured in serum and urine from rats with experimental nephrotic syndrome (NS) for 20 days after a single injection of puromycin aminonucleoside (PAN). Control values for Cp in serum and urine were: 0.23 +/- 0.01 mg/ml and 0.063 mg/day, and those for total protein were: 7.1 +/- 0.14 g/dl and 2.1 +/- 0.6 mg/day, respectively. It was found that: a) serum Cp decreased on day 6, remained low until day 10 (0.07 +/- 0.01 to 0.08 +/- 0.01 mg/ml), and returned to control levels on day 12; b) total serum protein decreased on day 4, reached the lowest value on day 6 (3.3 +/- 0.3 g/dl) and returned to control levels on day 16; c) Cp in urine increased on day 6, reached a peak value on day 8 (0.62 +/- 0.07 mg/day), then decreased but remained high on day 20; and d) total protein in urine increased on day 5, reached a peak value on day 10 (692 +/- 59 mg/day) and returned to control values on day 20. There was a close association between the levels of Cp and total protein in serum and urine. The decrease of circulating Cp indicates that a typical acute phase response does not occur in the PAN-nephrotic rats. The loss of Cp in the urine of the nephrotic rats may contribute to the decrease in the serum levels of this protein.

Animals↗
PubMedDate not supplied

Rabbit ceruloplasmin: purification and partial characterization.

Rabbit ceruloplasmin (Cp) was purified after solid ammonium sulfate precipitation to 60% final saturation by a two-step column chromatography procedure, utilizing DEAE-Sephadex A-50 and changing the NaCl concentration in the buffer to 0.16 M to achieve the isolation of the protein. The purified Cp was used to prepare antibodies in guinea pigs that were used afterwards to determine the Cp concentration in normal rabbits and in rabbits with an experimentally induced chronic anemia. The molecular weight of rabbit Cp determined by SDS-PAGE was 125,000 and a high molecular weight Cp of 200,000 comprising 8% of the total purified protein was also found. An optical density ratio (610 nm/280 nm) of 0.0475 and a molar extinction coefficient of 7625 were obtained. Copper determinations yielded a value of 0.24% that corresponds to 5 copper atoms per molecule. The staining of Cp following discelectrophoresis in polyacrylamide gels also showed a two band pattern.

Animals↗
PubMedDate not supplied

A study of erythropoiesis and iron metabolism in the rabbit in vivo. I. Characterization and limits of the physiological response.

1. An experimental model system was developed in the rabbit to study the transport of iron and the erythropoietic response to chronic bloodletting. 2. This model presents certain novel features as the capacity to measure total red blood cell production and total hemoglobin production in a daily basis. 3. Daily red blood cell production and output of hemoglobin are directly proportional to the volume of blood extracted. The limits of the erythropoietic response were determined. 4. When only minimal bloodletting was performed (3-6 ml blood/kg body weight) a normocytic response was obtained; with the removal of larger volumes of blood, a switch to macrocytic anemia was observed. Cats and guinea pigs responded in a similar fashion. 5. After induction of macrocytic anemia, the diameter of erythroid precursor cells in the bone marrow of the long bones increased and their numbers increased 11.5-fold.

Anemia↗