![Fig. 5. Evidence that 5-HT–induced apoptosis in BL cells is not due to oxidative stress. / (A) L3055 cells at 105/mL were treated with 10 to 100 μM of the MAO inhibitor pargyline in the presence of control medium or 125 μM 5-HT, as indicated. Cells were cultured for 24 hours in flat-bottomed microwells, and DNA synthesis was assessed by [3H]Tdr incorporation as for Figure 1A. (B) As for panel A, but cells were treated with concentrations indicated for the selective MAO-A and MAO-B inhibitors clorgyline and deprenyl, respectively. Data are represented as the mean ± SEM of 3 separate experiments. Note that cells used in panel A were of later passage (passages 40-45) than those in panel B (passages 60-65). (C) L3055 cells were cultured at 105/mL for 6 hours in control medium (histogram in bold), with 150 μM 5-HT (i) or 30 μM H2O2 (ii). OxyDNA-FITC conjugate was used to stain 8-oxodGuo residues on oxidatively damaged DNA. Data shown are representative of 3 identical experiments.](https://ash.silverchair-cdn.com/ash/content_public/journal/blood/99/7/10.1182_blood.v99.7.2545/6/h80722355005.jpeg?Expires=1724238220&Signature=zSc43naw3bA7v214N~2IqV8v3OWpEmPKs4~qKptR7zoGQrur28B3uQo1bzUTMJcEK3-zQbKLO3InGkGmpZ2cPbgJEQqPhv61uPyKfpBrg6aQ0KsWL51FuUuMlt6Qo1OLY0fAqth7oxImV4SkHD-I4Vipz9RyOhjGzEOyUoQIsCMFf7ZPt6Ywh9YZYJHm0p8z24BZAAnbaIqyWP9TMXhQFCbwf727W9mTi36N5pfdHNN1Xh3qVSYX-gKT0fmN4oB8~ezb0rApGunx4sKY0dpgr2eAMKO4yrj7DCviK8vwO0LqPzpuMBKOZLOiRxwTFhHUoY0Lz4smYii7iDhPrQqAxg__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Evidence that 5-HT–induced apoptosis in BL cells is not due to oxidative stress.
(A) L3055 cells at 105/mL were treated with 10 to 100 μM of the MAO inhibitor pargyline in the presence of control medium or 125 μM 5-HT, as indicated. Cells were cultured for 24 hours in flat-bottomed microwells, and DNA synthesis was assessed by [3H]Tdr incorporation as for Figure 1A. (B) As for panel A, but cells were treated with concentrations indicated for the selective MAO-A and MAO-B inhibitors clorgyline and deprenyl, respectively. Data are represented as the mean ± SEM of 3 separate experiments. Note that cells used in panel A were of later passage (passages 40-45) than those in panel B (passages 60-65). (C) L3055 cells were cultured at 105/mL for 6 hours in control medium (histogram in bold), with 150 μM 5-HT (i) or 30 μM H2O2 (ii). OxyDNA-FITC conjugate was used to stain 8-oxodGuo residues on oxidatively damaged DNA. Data shown are representative of 3 identical experiments.
