Contenidos hepáticos y renales de hierro y cobre en ratas tratadas con cadmio y zinc / Hepatic and renal contents of ¡ron and cooper in rats treated with cadmium and zinc

Se realizó un estudio de la influencia de la administración de Cd vía intrape-ritoneal (ip), y de Cd (ip) y Zn vía subcutánea (se) sobre los niveles de Fe y Cu en hígado y riñones. Después de cinco semanas ambos grupos de tratamiento (Cd y Cd+Zn) mostraron pesos de hígados anormalmente bajos con respecto al peso corporal total.Los grupos de ratas tratados sólo con Cd presentaron niveles de Fe en ambos órganos (hígados y riñones) menores que los observados en el grupo control. Los niveles de Cu en hígados permanecen practicamente constantes en función del tiempo de tratamiento mientras que el contenido renal de Cu se incrementó significativamente después de cinco semanas de tratamiento.Con respecto a los grupos de animales tratados con Cd+Zn, el contenido hepático de Fe disminuye durante la primera semana pero tiende a normalizarse después de cinco semanas, lo cual sugiere el papel protector del Zn frente a la depleción hepática de Fe inducida por Cd. El Fe renal así como el Cu renal y hepático presentaron un comportamiento similar. Se observan disminuciones e incrementos significativos después de una y cinco semanas respectivamente, lo cual se relaciona con una mayor síntesis de metalotioneínas y redistribución anómala de los metales esenciales (AU)

Protective effects of zinc on cadmium toxicity in rodents.

A study of acute and subacute toxicity of cadmium ions [Cd(II)] was carried out on male Swiss mice and Sprague-Dawley rats with and without previous administration of zinc chloride. The LD50 of Cd(II) as cadmium sulfate (ip) was lower in animals previously given 10 mg/kg of zinc(II) chloride (sc). Factors such as animal weight variations, biochemical parameters, and accumulation patterns of Cd(II) and Zn(II) were taken into consideration when the subacute toxicity was evaluated. Alteration of the activities of glutamic pyruvic transaminase (GPT) and of glutamic oxaloacetic transaminase (GOT) was observed in short-term-exposure (<6 h) cases. These alterations reverted to normal after 1 wk. The activity of alkaline phosphatase (ALP) and the concentrations of cholesterol and triglycerides in serum are also changed, especially so in the groups given CdSO4 alone. In the experimental groups treated with ZnCl2 prior to administration of cadmium, proteinuria was detected 5 wk after the treatment. Also at 5 wk, both Zn-treated and nontreated groups showed an abnormally low liver mass with respect to total body mass. Both Cd and Zn are retained preferentially in the liver but show also in the kidneys. If CdSO4 and ZnCl2 are given simultaneously, especially after 1 wk of treatment, Cd is accumulated in greater amounts in these organs when compared to the groups given only cadmium sulfate.

Elevated levels of paf-acether in blood of patients with type 1 diabetes mellitus.

Infusion of paf-acether (paf, first described as platelet-activating factor) into animals stimulates glycogenolysis and lipolysis and decreases insulin levels. This study reports a 50-fold increase in blood levels of paf in patients with Type 1 insulin-dependent diabetes mellitus without micro or macrovascular complications (1.07 +/- 0.42 ng/ml, n = 10) as compared with healthy volunteers (0.04 +/- 0.02 ng/ml, n = 9). By contrast, paf is not statistically elevated (p greater than 0.05) in patients with Type 2 non-insulin-dependent, diabetes mellitus with lipid abnormalities and micro or macrovascular complications (0.32 +/- 0.18 ng/ml, n = 9). In the three groups same levels of paf precursors and acetylhydrolase activity (the enzyme which inactivates paf) were noted suggesting an increase in paf biosynthesis by Type 1 diabetic patients. Elevated paf levels could perpetuate hyperglycaemia and tend to promote or accentuate micro or macrovascular complications. This study adds another biological difference between Type 1 and Type 2 diabetes.