Phenylethanolamine N-methyltransferase gene expression in transplanted human heart

Background. Phenylethanolamine N-methyltransferase (PNMT) is an enzyme involved in the epinephrine synthesis. The aim of this study was to investigate PNMT gene expression in the transplanted human heart in relation to the time elapsed from heart transplantation (HTx) and selected clinical characteristics. Patients and Methods. The messenger RNA (mRNA) levels of PNMT in myocardial tissue were determined in 22 (21 males) patients at 0-12 years after HTx. Relative quantification of mRNA levels was performed using reverse transcription and polymerase chain reaction (RT-PCR) for correlation with heart rate (HR), blood pressure (BP), parameters of heart rate variability, and graft systolic and diastolic functions. Results. During the first 3 years after HTx, PNMT mRNA levels were higher (mean ± SEM) (0.75 ± 0.06; n = 12) compared with later years (0.33 ± 0.06; n = 10); (P