This Article Full Text (PDF) Submit a related Letter to the Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via Google Scholar Google Scholar Articles by RISTIMÄKI, A. Articles by VIINIKKA, L. Search for Related Content PubMed PubMed Citation Articles by RISTIMÄKI, A. Articles by VIINIKKA, L.

Human Milk Stimulates Prostacyclin Production by Cultured Human Vascular Endothelial Cells^*

Children’s Hospital (A.R., K.P., J.P., L.V.) and the Departments of Obstetrics and Gynecology (O.Y.), University of Helsinki SF-00290 Helsinki, Finland

Address all correspondence and requests for reprints to: Ari Ristimäki, Kuusitie 5 A 45, 00270 Helsinki, Finland.

Prostacyclin (PGI₂) is an antithrombotic and vasodilatory factor, which is produced mainly by the vascular endothelium. Little is known about how this process is regulated. We investigated the effect of human milk on PGI₂ synthesis by human vascular endothelial cells by measuring its stable metabolite, 6-keto-prostaglandin F₁, by RIA. Human milk induced dose- and time-dependent stimulation of PGI₂ production, whereas cow’s milk was ineffective. The lowest concentration of human milk that stimulated the production of PGI₂ was 0.1%, and 10% induced a 2.4- to 3.4-fold increase. The effect of human milk was detectable after 2 h and was blocked by inhibitors of transcription, translation, and cyclooxygenase. Boiling abolished the activity, but acetone extraction enhanced it. A 10% concentration of acetone-extracted human milk stimulated the release of endothelial cell PGI₂ by 6.6-fold. In human milk samples we found no correlation between the amount of immunoreactive epidermal growth factor (EGF) and the activity stimulating PGI₂ synthesis. Furthermore, EGF antibodies did not inhibit the activity. This is the first demonstration that human milk stimulates PGI₂ production by endothelial cells. We conclude that human milk is a potent inducer of PGI₂ production by human vascular endothelial cells and that the stimulatory activity is not due to EGF.

^* This work was supported by the Sigrid Juselius Foundation, the Academy of Finland, the Foundation for Pediatric Research (Helsinki, Finland), the Ida Montini Foundation, the Finnish Foundation for Cancer Research, and the Finnish Culture Foundation.

Received March 3, 1990.