Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.36 (hyaluronidase)
 4,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An enriched fraction of human placental cells that synthesize and release both placental lactogen (hPL) and hCG was obtained by isopycnic centrifugation of collagenase/hyaluronidase-dispersed cells through a density gradient of 40% Percoll. The enriched cells, which banded at a density of approximately 1.01 g/ml, comprised 10-15% of the total DNA. During the first 24 h after attachment, the cells released 50-250 ng hPL and 4-10 mIU hCG/10(6) cells. Thereafter, the rate of hPL release decreased, while the rate of hCG and [35S]trichloroacetic acid-precipitable protein release remained constant. The enriched cells responded to phospholipase A2, low extracellular calcium, and (Bu)2cAMP in a manner similar to that of placental explants. Phospholipase A2 (0.1 and 1 U/ml) stimulated hPL release by 270% and 568%, respectively, and low extracellular calcium (0-0.18 mM) stimulated hPL release by 48%. (Bu)2 cAMP (1 mM) stimulated hCG release by 42%, but had no effect on hPL. Estradiol (10(-5)-10(-12) M) and progesterone (10(-5)-10(-10) M) had no effect on the synthesis and release of either hPL or hCG over a 6-day period. In addition, insulin (8.3 X 10(-7) M) and changes in medium glucose content (0-5 mg/ml) had no effect on hPL release over a 72-h period. Since the enriched trophoblast cells respond to provocative stimuli in a manner similar to that of explants and placental fragments, this cell population is a useful model system for investigations of the cellular mechanisms of hPL and hCG release.
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PMID:Characterization of the synthesis and release of human placental lactogen and human chorionic gonadotropin by an enriched population of dispersed placental cells. 630 87

A simple three-enzyme treatment of collagenase, dispase and hyaluronidase on finely minced chick oviduct yields clumps of 50-150 cells. These cells attach to collagen-treated dishes and survive in culture for at least 2 weeks without subculturing. Oviduct cell cultures can also be induced to grow. Estradiol or epidermal growth factor (EGF) induce a 40% increase in cells in 4 days when cultures are grown in serum levels that do not support growth. Serum from estrogen-stimulated chicks promotes rapid cellular proliferation (doubling times of 1-2 days). Sera from estrogen withdrawn chicks, laying hen or horse do not support as rapid proliferation. The oviduct growth-promoting factors in serum from estrogen-stimulated chicks are not steroids or fibroblast growth factors (FGF). Removal of steroids from these sera by charcoal treatment or delipidization does not decrease the rate of growth. The addition of 1-100 nM estradiol does not increase a serum's ability to promote growth. Purified FGF or platelet-derived growth factor (PDGF) do not induce oviduct proliferation. These results were reproduced in oviduct cell cultures started from estrogen-stimulated and withdrawn chicks as well as laying hens. Thus the factors in serum from estrogen-stimulated chicks that promote rapid oviduct growth are induced by estrogen treatments in vivo, but do not seem to be only steroids.
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PMID:The chick oviduct in tissue culture. I. Initial characterization of growing primary oviduct tissue cultures. 633 49