G. Bellone et al., Association between elevated prolactin levels and circulating erythroid precursors in dialyzed patients, P SOC EXP M, 223(4), 2000, pp. 367-371
Citations number
26
Categorie Soggetti
Medical Research General Topics
Journal title
PROCEEDINGS OF THE SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE
The prolactin (PRL) receptor (R), a member of the cytokine hemopoietin rece
ptor superfamily, has been shown to activate early differentiation steps al
ong the erythroid pathway. In particular PRL, a product of bone marrow stro
ma, induces functional erythropoietin (EPO)-R on CD34(+) hemopoietic progen
itors. In this study, expression of EPO-R mRNA and responsiveness to EPO we
re assessed on enriched hemopoietic progenitor cells (HPC) from seven hyper
prolactinemic and three normoprolactinemic patients and two normal subjects
. Expression of EPO-R mRNA by semiquantitative reverse transcriptase-polyme
rase chain reaction (RT-PCR) was found in HPC of four out of seven hyperpro
lactinemic patients but not in normoprolactinemic patients or normal donors
. Development of EPO-dependent Colony Forming Unit-Erythroid (CFU-E) coloni
es in semi-solid medium was observed only in hyperprolactinemic patients (s
ix out of seven). A much higher number of CFU-E colonies was observed in th
e four patients with a positive EPO-R message. We conclude from these data
that abnormally high levels of PRL may increase the number of EPO-responsiv
e hemopoietic precursors in vivo as they do in vitro. Since hyperprolactine
mia associates in these patients with depressed EPO production, it may be r
egarded as a compensatory mechanism for the reduced availability of the hem
opoietic factor.