Effect of tumour necrosis factor alpha on rat blastocyst growth and glucose metabolism.
Tumour necrosis factor alpha (TNF-alpha) synthesis has recently been described in the uterus during the preimplantation phase of pregnancy. The present study was undertaken to determine whether preimplantation embryos are a potential target for TNF-alpha in rats. First, the expression of TNF-alpha receptors by blastocysts was demonstrated by ligand binding assay with human 125I-labelled TNF-alpha and reverse transcription-amplification for the p60 receptor form. The functionality of these receptors was then assessed by incubating blastocysts with 3 nmol mouse TNF-alpha l-1 in vitro and determining their morphology and the number of cells after 24 h. At that concentration, cell proliferation in blastocysts was inhibited by TNF-alpha but this was not accompanied by any change in the morphology of the embryos. Similar results were obtained when lower doses of TNF-alpha (30 and 300 pmol l-1) were tested. The rate of glucose consumption of rat blastocysts exposed to 3 nmol TNF-alpha l-1 was not altered when they were incubated with the cytokine for 4 h, but the rate of glucose incorporation decreased over the same period. Our data indicate that rat blastocysts are responsive to physiological concentration of TNF-alpha and that this cytokine has the potential to influence the preimplantation development of rats.
Pampfer
S
S
Physiology of Human Reproduction Research Unit, University of Louvain, School of Medicine, Brussels, Belgium.
Moulaert
B
B
Vanderheyden
I
I
Wuu
Y D
YD
De Hertogh
R
R
D000818:Animals; D001755:Blastocyst / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D005314:Embryonic and Fetal Development / Q000187:drug effects*; D005947:Glucose / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D018124:Receptors, Tumor Necrosis Factor / Q000032:analysis; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000494:pharmacology*
D012333:RNA, Messenger; D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha; D005947:Glucose