Search PubMed⌕ Search

Biomedical subjects

A Y Warren

Publications and source records attributed to A Y Warren.

21 records · Page 2Linked to original sources

Production of active and inactive renin by cultured explants from the human female genital tract.

Myometrium, decidua, chorio-decidua and amnion were collected from women undergoing caesarean section and from pregnant women at hysterectomy and hysterotomy for comparison with myometrium, cervix and endometrium taken from non-pregnant women at hysterectomy. Homogenates of chorio-decidua and amnion contained the largest concentrations of active and inactive renin. Cultured explants of all tissues except amnion were found to produce both types of renin. The percentage of active renin produced before 20 days of culture was significantly greater in cultures of chorio-decidua than in those of myometrium (P less than 0.0005) or decidua vera (P less than 0.025), which suggests that renin synthesis in vivo is probably confined to the chorio-decidua.

Amnion↗

Active and inactive renin in human seminal plasma.

The occurrence of renin and renin substrate has been described in human seminal plasma. Mean levels of active and total renin were higher in seminal plasma than in normal male plasma (7.1 compared to 3.8 and 38.5 compared to 24.6 ng/ml/hr, respectively). The differences were not statistically significant. Renin substrate concentrations were very low compared to male plasma levels, which suggests that renin may function either in tissues of the male genital tract prior to secretion into the seminal plasma or may be important following ejaculation in the female genital tract.

Angiotensin I↗

Vascular endothelial growth factor but not placental growth factor promotes trophoblast syncytialization in vitro.

OBJECTIVE: The object of this study was to determine the effect of epithelial growth factor (EGF), vascular endothelial growth factor (VEGF), and placental growth factor (PlGF) on the differentiation of first-trimester and term cytotrophoblasts. METHODS: The first-trimester trophoblasts were isolated from villous tissue obtained at suction termination (n = 5), and the term trophoblasts were isolated from placentas (n = 6) at elective cesarean. Cultured cells were stimulated with EGF, VEGF, or PlGF at 0.5, 5, and 50 ng/mL, in the presence or absence of N(G)-nitro-L-arginine methyl ester hydrochloride (10(-4) M). Syncytialized trophoblasts were identified by immunostaining with antidesmosomal protein and anti-cytokeratin-7, whereas nuclei were counted in each syncytia using hematoxylin. RESULTS: Without treatment, background levels of syncytialization were significantly higher in term preparations than first-trimester cells. With VEGF and EGF, the number and size of syncytia increased significantly for the first-trimester cytotrophoblasts (P <.05). Neither VEGF nor EGF had any effect on the syncytialization of cultured cells at term. Nitric oxide showed no involvement in syncytial induction, and PlGF had no effect on syncytialization of cytotrophoblasts, from either the first or third trimester. CONCLUSION: Both EGF and VEGF appeared to enhance the in vitro syncytialization of first trimester cytotrophoblasts.

Cell Differentiation↗