Stimulation of alpha-adrenergic receptor augments the production of macrophage-derived tumor necrosis factor
| Autor: | R N Spengler, R M Allen, D G Remick, R M Strieter, S L Kunkel |
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| Rok vydání: | 1990 |
| Předmět: | |
| Zdroj: | The Journal of Immunology. 145:1430-1434 |
| ISSN: | 1550-6606 0022-1767 |
| Popis: | Accumulating evidence supports the hypothesis that neuroendocrine hormones may participate in immunologic processes. In our study we have determined that UK-14304 (UK) and norepinephrine (NE), both alpha 2-adrenergic agonists, can augment LPS-stimulated TNF from elicited macrophages (MO). The increase in TNF production was concentration dependent with an EC50 for UK and NE of 8.1 +/- 2.6 and 0.52 +/- 0.17 nM, respectively. The concentration-effect curve for UK and NE was shifted to the right by the alpha 2-antagonist yohimbine (10(-6) M), with new EC50 of 49.7 +/- 12.2 (p less than 0.001) nM and 10.3 +/- 22 nM. The augmenting effect of UK on MO TNF production was assessed over a 7 log LPS response curve. Within a single population of MO 10 nM UK shifted the LPS-induced TNF curve eightfold to the left with the greatest increase in TNF production at lower LPS concentrations. At the transcriptional level, Northern blot analysis demonstrated that UK increased LPS-induced TNF mRNA accumulation. This augmentation in TNF mRNA accumulation was blocked by yohimbine. The presence of a MO alpha-adrenergic receptor was established by demonstrating binding of the alpha 2-adrenergic antagonist 3H-yohimbine to membranes prepared from MO. This binding was rapid, saturable, reversible, and blocked by UK, clonidine, and phentolamine. These investigations support the role of alpha 2 adrenergic agonists as immunostaining compounds that may regulate cytokine production during an inflammatory response. |
| Databáze: | OpenAIRE |
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