Treatment of the AML-193 leukemic cell line with phorbol myristate acetate (PMA) resulted in the loss of their ability to proliferate in response to GM-CSF or IL-3. This was not due to a change in number or affinity of GM-CSF receptors, but possibly resulted from an other cellular mechanism. The AML-193 differentiated cells acquired the ability to phagocytose glutaraldehyde-fixed E.
View Article and Find Full Text PDFAn interleukin 1 (IL 1) inhibitor is secreted into culture medium by a human promyelocytic cell line, H-161, upon stimulation with (PMA) and recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF). Since the morphological characteristics of this cell line were macrophage-like, human monocytes were tested for their ability to produce similar activity using the same induction conditions. Upon induction of adherent peripheral blood monocytes with rhGM-CSF and/or PMA, an IL 1 antagonistic activity was found in the cell supernatants, as determined by IL 1 receptor binding assay, using the murine EL-4.
View Article and Find Full Text PDFAn influence of thyroid status on the secretory activity of hypothalamic dopaminergic neurons was observed in adult rats and its involvement in the regulation of prolactin (PRL) secretion was examined. The secretory activity of the tuberoinfundibular dopaminergic (TIDA) neurons was evaluated by measurement of dopamine (DA) biosynthesis in the neurons and DA release into hypophysial portal blood. The accumulation of DA and PRL in the adenohypophysis as well as PRL concentration in plasma were also estimated, and the various parameters were studied in thyroidectomized (TX), sham TX, TX rats treated for 7 days with thyroxine (T4; 20 micrograms/kg body weight daily) as well as in intact rats treated similarly with T4.
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