['The infusion of amphotericin-B (AmB) often produces clinically distressing rigors and chills, which promptly abate with intravenous injection of meperidine, although its mechanism of action is unknown.', 'To examine the effects of meperidine on the transcription or secretion of Interleukin 1 beta (IL-1 beta) in human mononuclear leukocytes (MNL) exposed in vitro to the lipopolysaccharide (LPS) contained in Escherichia coli endotoxin or to AmB.', 'Blood was drawn from eight healthy adult volunteers. The blood was centrifuged, and the layer containing MNL was separated; incubated with various combinations of medium, meperidine, and AmB; then tested for IL-1 content to determine the effect of meperidine on MNL secretion of IL-1 beta. To determine the effect on MNL transcription of IL-1 beta, the RNA was extracted from cells and the IL-1 beta was measured using one of two different methods.', 'Incubation of human MNL in the presence of LPS or AmB significantly increased transcription of IL-1 beta mRNA and secretion of IL-1 beta. Addition of meperidine to these cultures significantly reduced LPS-induced, but not AmB-induced, secretion of IL-1 beta in vitro. Meperidine did not alter IL-1 beta mRNA levels in MNL exposed to LPS or AmB.'] Does meperidine attenuate the secretion but not the transcription of interleukin 1 beta in human mononuclear leukocytes?