title: Platelet-activating factor in human endometrium.
abstract: Platelet-activating factor (PAF) is a phospholipid actively produced by human endometrium and deeply involved in the processes of ovoimplantation and labor. We recently found that PAF represents a new autocrine growth factor for a human adenocarcinoma cell line, HEC-1A. Indeed, biologically active PAF is synthesized by HEC-1A cells, under progesterone control. In HEC-1A cells, PAF regulates intracellular calcium concentration ([Ca2+]), DNA synthesis and expression of early oncogenes. All these effects are blocked by the receptor antagonist L659,989. However, while nanomolar concentrations of PAF mobilize [Ca2+], only micromolar concentrations affect cell growth, suggesting heterogeneity of PAF receptors or signaling. Two distinct populations of PAF receptors are present in HEC-1A cells, which bind PAF in nanomolar and micromolar concentrations, respectively. Since HEC-1A cells are producing elevated concentrations of PAF and micromolar concentrations of the PAF antagonist L659,989 inhibit cell proliferation, an autocrine role for PAF is suggested in HEC-1A cells.
authors.affiliation: Dipartimento di Fisiopatologia Clinica, Università di Firenze, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Baldi
authors.forename: L
authors.initials: L
authors.lastname: Bonaccorsi
authors.forename: G
authors.initials: G
authors.lastname: Finetti
authors.forename: M
authors.initials: M
authors.lastname: Luconi
authors.forename: M
authors.initials: M
authors.lastname: Muratori
authors.forename: T
authors.initials: T
authors.lastname: Susini
authors.forename: G
authors.initials: G
authors.lastname: Forti
authors.forename: M
authors.initials: M
authors.lastname: Serio
authors.forename: M
authors.initials: M
authors.lastname: Maggi
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism; D004717:Endometrium / Q000502:physiology*; D005260:Female; D006133:Growth Substances / Q000502:physiology; D006801:Humans; D010972:Platelet Activating Factor / Q000502:physiology*; D014407:Tumor Cells, Cultured; D014594:Uterine Neoplasms / Q000378:metabolism
chemical_list: D006133:Growth Substances; D010972:Platelet Activating Factor