Preeclampsia usually occurs after week 20 of gestation and features hypertension and an increased peripheral vascular resistance. The mechanisms are unknown (1). Several lines of evidence implicate angiotensin II (Ang II) and its binding site, the AT 1 receptor. Preeclamptic patients manifest exaggerated pressor responses to Ang II. Gant et al. (2) infused Ang II into pregnant patients from week 10 of pregnancy onward and observed that those who later developed sustained hypertension required diminishing amounts of Ang II to obtain a similar pressor response. One possible explanation for this phenomenon might be increased expression of the AT 1 receptor. Baker et al. (3) also performed Ang II infusion experiments in pregnant patients and identified five patients who subsequently developed hypertension after week 20. These women were compared with seven who did not develop hypertension. The platelets of the preeclamptic women exhibited increased calcium signaling and increased binding sites for Ang II. The authors suggested increased stimulus-effect coupling in terms of Ang II responses in preeclamptic patients. We also observed increased cytosolic calcium responses in the platelets of preeclamptic patients in response to Ang II (4). However, circulating levels of Ang II are not increased in preeclampsia (5-7). In an earlier study of patients with essential hypertension, we observed a remarkably high incidence of circulating antibodies that cross-reacted with the α1-adrenoceptor and stimulated its signaling mechanism (8). In the present study, we tested the hypothesis that circulating antibodies to a vascular receptor might be responsible for the hypertension observed in preeclampsia. We employed a bioassay of beating neonatal rat cardiomyocytes, as well as Western blotting and confocal microscopy. We found that immunoglobulin from preeclamptic women contains a factor that binds to, and stimulates, the AT 1 receptor. MethodsCell culture. Isolation and cultivation of neonatal heart cells were performed as described previously (9). Briefly, single cells were dissociated from the minced ventricles of Wistar rats (1-2 days old) with a 0.25% solution of crude trypsin and were cultured as monolayers with a density of 800 cells/mm 2 in Halle SM 20-I medium equilibrated with humidified air. The medium contained 10% heat-inactivated FCS and 2 µmol/l fluorodeoxyuridine (Serva, Heidelberg, Germany) the latter to prevent proliferation of nonmuscle cells. On the third or fourth days, the cells were incubated for 2 h in 2 ml fresh serum-containing medium. Seven to 10 selected cells or synchronously contracting cell clusters per flask were counted for 15 s. This procedure was Immune mechanisms and the renin-angiotensin system are implicated in preeclampsia. We investigated 25 preeclamptic patients and compared them with 12 normotensive pregnant women and 10 pregnant patients with essential hypertension. Antibodies were detected by the chronotropic responses to AT 1 receptor-mediated stimulation of cultured neonatal rat cardio...
The incidence of preterm delivery is significantly elevated in twin pregnancies and consequently the incidence of low- and very-low-birth-weight-infants and perinatal mortality. Preterm delivery is the main reason why twin pregnancies are at a higher risk for an adverse neonatal outcome and thereby cause considerable costs.
Secondary side-effects often occur in women undergoing hormonal stimulation treatment with clomiphene citrate. In general 10.4% of women experience hot flushing, 5.5% have complaints caused by enlargement of the ovaries and 3.5% experience central nervous symptoms (nervousness, sleeplessness, headaches, visual disturbances, vertigo). During ovarian stimulation with clomiphene citrate for in-vitro fertilization, a 32 year old patient developed psychotic symptoms, commencing 3 days after initiation of treatment. Hospitalization in the psychiatric ward became necessary when severe formal and rational thought disturbances arose together with perceptory and sensory delusions. Under neuroleptic treatment the symptoms improved. Nevertheless, follow-up psychiatric care on an outpatient basis was deemed necessary. The infertility treatment was continued with human menopausal gonadotrophin stimulation. Psychiatric instability occurred neither at this point nor during the 2 year follow-up observation period. Both an exogenous psychosis (ICD F23.9) as well as the exacerbation of an endogenous psychosis (ICD F29) may be considered for the differential diagnosis. The stimulation with clomiphene citrate in connection with the physical and psychic stress of the infertility therapy can be regarded as the trigger factor. For patients with evidence of psychiatric illness in their case history, ovulation-inducing substances such as clomiphene citrate should be implemented with particular care.
A common mutation in the factor V gene, the Leiden mutation, is the most frequent genetic cause of resistance to activated protein C (APC). Recent studies have shown that the prevalence of APC resistance is associated with severe pregnancy-induced hypertension (PIH). Our objective was to determine whether the factor V Leiden mutation is more prevalent in patients who developed severe PIH than in normotensive pregnant women. In 70 women with a history of severe PIH, of whom 15 had pre-eclampsia, we investigated common coagulation factors as well as APC resistance (factor V related). We found that seven of these 70 women showed low values for APC. Out of these, five were heterozygous and none was homozygous for factor V Leiden mutation. In a control group of normotensive pregnant women we found a 3.0% rate of APC resistance and a 3.0% rate of carriers of the Leiden mutation. These results indicate a significantly higher prevalence of both APC resistance and factor V Leiden mutation in women with severe PIH. Placental infarctions and micro-embolisms are considered to be one of the principle pathophysiological changes in severe PIH. Our results suggest that APC resistance is a risk factor for severe PIH, in addition to its well-known role in macrothrombo-embolism.
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