21 research outputs found

    Monitoring female reproductive function by measurement of fecal estrogen and progesterone metabolites in the white-faced saki (Pithecia pithecia)

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    A simple method for extracting and measuring ovarian steroids in feces is applied to the ovarian cycle, pregnancy, parturition, and period of lacta tional amenorrhea in Pithecia pithecia. Small amounts of wet, unmixed feces were combined with a modified phosphate buffer, shaken, centri fuged, and decanted, and the supernatant was directly measured for es trogen and progesterone metabolites by enzyme immunoassays. Urinary estrogen and progesterone metabolite measurements were compared to paired fecal measurements to determine the degree to which fecal hor mone levels detected the same ovarian events as urinary measurements. The correlation coefficients for the relationship between urinary and fecal hormones for individual animals studied (n = 5) were found to be statis tically significant in every case except one sexually immature animal. The application of the method presented here demonstrates that simple solu bilization and non-radiometric measurement of ovarian steroids excreted in feces reliably reflect reproductive events in Pithecia pithecia. 0 1994 Wiley-Liss, Inc.Se aplica un método sencillo para extraer y medir los esteroides ováricos en las heces al ciclo ovárico, la gestación, el parto y el período de amenorrea de la lactancia en Pithecia pithecia. Se combinaron pequeñas cantidades de heces húmedas y sin mezclar con un tampón fosfato modificado, se agitaron, se centrifugaron y se decantaron, y el sobrenadante se midió directamente para los metabolitos de estrógeno y progesterona mediante inmunoensayos enzimáticos. Las mediciones de los metabolitos de estrógeno y progesterona en la orina se compararon con las mediciones fecales emparejadas para determinar el grado en que los niveles hormonales fecales detectaban los mismos eventos ováricos que las mediciones urinarias. Los coeficientes de correlación para la relación entre las hormonas urinarias y fecales para los animales individuales estudiados (n = 5) resultaron ser estadísticamente significativos en todos los casos, excepto en un animal sexualmente inmaduro. La aplicación del método aquí presentado demuestra que la simple solubilización y la medición no radiométrica de los esteroides ováricos excretados en las heces reflejan de forma fiable los eventos reproductivos en Pithecia pithecia.Universidad Nacional, Costa Rica.Escuela de Medicina Veterinari

    Continuously delivered ovarian steroids do not alter dendritic spine density or morphology in macaque dorsolateral prefrontal cortical neurons

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    Aged ovariectomized female monkeys, a model for menopause in humans, show declines in spine density in the dlPFC and diminished performance in cognitive tasks requiring this brain region. Previous studies in our laboratory have shown that long-term cyclic treatment with 17β-estradiol (E) produces an increase in spine density and in the proportion of thinner spines in layer III pyramidal neurons in the dorsolateral prefrontal cortex (dlPFC) of both young and aged ovariectomized rhesus monkeys. Here we used 3D reconstruction of Lucifer yellow-loaded neurons to investigate whether clinically relevant schedules of hormone therapy would produce similar changes in prefrontal cortical neuronal morphology as long-term cyclic E treatment in young female monkeys. We found that continuously delivered E, with or without a cyclic progesterone treatment, did not alter spine density or morphology in the dlPFC of young adult OVX rhesus monkeys. We also found that the increased density of thinner spines evident in the dlPFC 24 hours after E administration in the context of long-term cyclic E therapy is no longer detectable 20 days after E treatment. When compared with the results of our previously published investigations, our results suggest that cyclic fluctuations in serum E levels may cause corresponding fluctuations in the density of thin spines in the dlPFC. By contrast, continuous administration of E does not support sustained increases in thin spine density. Physiological fluctuations in E concentration may be necessary to maintain the morphological sensitivity of the dlPFC to E
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