404 Platenta (1991), Vol. 12

EFFECTS OF AGEING ON THE ULTRASTRUCTURE OF RAT DECIDUA AND ENDOMETRIUM C. J. P. Jones, J. D. Aplin’, J. Mulhollandb & S. R. Glasse# (Departments of Pathological Sciences & * Obstetrics/Gynaecology, Manchester University, Manchester Ml3 9PT, UK and bDepartment of Cell Biology, Baylor College of Medicine, Houston, Texas 77030, USA)

The capacity of the decidualizing rat uterus to accept embryonic implantation becomes impaired after 1 year of age. In this study, we have examined the ultrastructure of decidua, and control endometrium, of rats between 4 and 18 months of age in order to identify differences associated with ageing that might account for this decrease in fertility. In the young animals, subluminal decidual cells formed close contacts with each other, with many junctional complexes, occasional interdigitations between apposing plasma membranes, and very little intercellular ground substance or matrix. In contrast to this, the decidua of older animals exhibited bundles of collagen fibrils between adjacent cells, more ground substance, and a dramatic decrease in the number of intercellular junctions. Massive accumulations of cytoplasmic intermediate filaments could be seen in the stellate cells of the mid-region of decidualiied uteri, and these were far more prominent in the older rats. In both decidua and control endometrium, ageing was accompanied by a striking increase in the density of collagen fibrils in the stroma. We propose that this is associated with impaired decidual differentiation including a reduction in the ability to form intercellular contacts. These changes may in turn be partly responsible for altered receptivity to implantation.

GLYCOSYLATION AND DESMIN EXPRESSION AS INDICES OF DECIDUAL DIFFERENTIATION IN THE RAT C. J. P. Jones, J. D. Aplin”, J. Mulhollandb & S. R. Glasserb (Departments of Pathological Sciences & a Obstetrics/Gynaecology, Manchester University, Manchester Ml 3 9PT, UK and bDepartment of Cell Biology, Baylor College of Medicine, Houston, Texas 77030, USA)

In the rat uterus, desmin is expressed in decidualizing cells; it is apparent in both primary and secondary decidua, but is undetectable in unstimulated stromal cells. We have compared the presence of desmin in early decidua with alterations in glycosylation as detected by lectin binding. Dramatic differences in the pattern of glycosylation between primary and secondary decidua were found, with the primary decidua showing an abundance of tetra-antennary non-bisected N-linked sequences as shown by staining with leucophytohaemagglutinin (kidney bean) and N-ace@ lactosamine sequences with some terminal galactosyl residues which bound Erythrina criktugalli (coral tree) agglutinin. There was a marginal increase in the number of sialyl residues expressed, with Maackia amurensis, Sambucus n&a (elderberry), LimaxJEavus (slug), and wheatgerm agglutinins all showing slightly increased binding. Both primary and, to a lesser extent, secondary decidua expressed increased quantities of bisected bi/tri-antennate complex N-linked sequences and repeated N-ace@ lactosamine chains which bound erythrophytohaemagglutinin (kidney bean), and Lycopersicon esdentum (tomato) agglutinin respectively. Much lectin binding was associated with an anastomosing pericellular network containing the cell surface and residual intercellular matrix. This may

Abstracts 405

reflect compression of stromal components due to decidual cell enlargement or neoglycosy- lation associated with the differentiation pathway.

FUNCTIONAL DIFFERENTIATION OF UMBILICAL VEIN ENDOTHELIAL CELLS FOLLOWING PREGNANCY COMPLICATED BY SMOKING OR DIABETES MELLITUS B. Karbowski, H.-J. Bauch’ & H. P. G. Schneider (Department of Obstetrics/Gynaecology, University of Munster, FRG and aInstitute of Arteriosclerosis Research, University of Munster, FRG)

Many endothelial cell functions that exert a regulative influence on fetal hemodynamics and placental perfusion are modulated by metabolites of arachidonic acid, in particular, prosta- glandins. We used an in vitro model system to study the possible role of the vascular endothelium in the pathogenesis of chronic placental insufficiency. We examined cell growth behaviour and prostaglandin metabolism in cultured umbilical vein endothelial cells from mothers exposed to the risk factors smoking and diabetes mellitus during pregnancy. We compared cells from smoking (n = 18) and diabetic mothers (n = 5) with cells from non- smoking, non-diabetic control individuals (n = 20). Endothelial cells from smoking and diabetic mothers grew less readily than control cells. The synthesis of prostaglandin PG12 and PGEZ, both potent vasodilators and platelet aggregation inhibitors, was significantly reduced in endothelial cells from smoking mothers and from mothers suffering from diabetes at various stages. Thus, reduced prostaglandin synthesis may be a cause of impaired placental perfusion in high risk pregnancies. Our results suggest that prostaglandin may play an important role in the etiology and pathogenesis of chronic placental insufficiency.

A DIFFERENTIAL SCREEN OF A PRE-ECLAMPTIC PLACENTAL cDNA LIBRARY J. W. Kasik (Division of Neonatology, MHMC/Case West Research University, Cleveland OH 44109, USA)

Placental tissue was obtained from a pregnancy complicated by pre-eclampsia and from four pregnancies uncomplicated by pre-eclampsia. Poly A+ RNA was purified from all five samples and a cDNA library was constructed using the RNA purified from the pre-eclamptic placenta (Uni-Zap XR, Stratagene, La Jolla, CA). Using duplicate lifts ofthe plated library, a differential screen was performed on a total of 15,000 plaques using random-primed reverse-transcribed radiolabeled cDNA probes generated from pre-eclamptic placental mRNA or a pooled sample of mRNA from the non-pre-eclamptic placentas. Twenty-three positive clones have been identified following second screens. These clones are currently being characterized by restriction digests and southern blotting. Final confirmation of positives will be made by performing northern blots against a panel of RNA representing a larger population of normal and pre-eclamptic pregnancies.