FIGURE 2.

Estrogen regulation of PEMT is transcript-specific. Using RNA isolated from primary hepatocytes cultured in the absence (−) or presence (+) of 100 nmol/liter moxestrol for the lengths of time noted, PEMT transcripts were quantified using transcript-specific primers by quantitative PCR. A, transcript A, initially the most abundant, was not responsive to hormone treatment. B, transcript B was significantly induced in response to hormone treatment at both 8 and 24 h after treatment. C, transcript C was the least abundant but was significantly induced in response to hormone treatment at 8 and 24 h. D, PEMT expression levels, presented as a ratio of treated/untreated for all transcripts (normalized to GAPDH), demonstrated significant induction of B (all time points tested) and transcript C (at the 8 and 24 h time points). E, RNA isolated from male human liver biopsies and primary human hepatocytes was subjected to transcript-specific quantitative PCR. For human biopsy samples, results are presented as an average for all subjects (n = 6), and for human hepatocytes, results are shown as an average of all untreated samples, across all time points. Transcripts A and B were significantly more abundant than transcript C. Transcript A was significantly more abundant than transcript B (n = 5–6/time point; *, p < 0.05; **, p < 0.01). Error bars, S.E.