Relationship between 3H-histamine uptake and H2-receptors in the human promyelocytic leukemia cell line HL-60.

Association of 3H-histamine (3H-H) with HL-60 cells was a time- and temperature-dependent process. At 37 degrees C, the association of 3H-H (50 fmole/10(6) cells) was maximal and constant 60 min after the addition of HL-60 cells, while there is no significant radioactivity associated with cells incubated at 4 degrees C during 120 min incubation. Under these conditions, the cell-associated radioactivity remains unchanged, even after a washout period and addition of large excess (10(-3) M) of histamine, indicating an irreversible interaction between histamine and HL-60 cells. The interaction of 3H-H with HL-60 cells depends on cell viability, cell concentration and was reduced by various metabolic inhibitors such as iodacetamide, dinitrophenol, sodium azide and ouabain. Histamine uptake by HL-60 cells was inhibited by a series of H1, H2 histamine agonists (impromidine, histamine, 4-MH, AET, PEA) and antagonists (cimetidine, oxmetidine, ranitidine, diphenhydramine), according to the following order of potencies: 1 greater than H, 4-MH greater than AET greater than PEA and H,C greater than DPH. Among the histamine analogs tested (acid N-acetyl histamine, imidazole, acid imidazole acetic and histidine), only the N-acetyl histamine acid was able to inhibit 3H-H uptake by HL-60 cells. Three antidepressant drugs (amitriptyline, imipramine, clomipramine) also antagonize 3H-H uptake by HL-60 cells, but this effect was only observed at toxic concentrations (10(-5) M and above) and was related to a loss of the cell viability.(ABSTRACT TRUNCATED AT 250 WORDS)