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Query: EC:3.4.24.3 (
collagenase
)
18,340
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Corpora lutea were surgically collected from superovulated ewes 36 h post-injection of human
chorionic gonadotropin
(hCG) (Day 2), dissociated (0.2%
collagenase
), plated, and maintained in culture Days 2-10 in Medium 199 supplemented with 5% calf serum. Accumulation of progesterone in the cultures did not decrease (p greater than 0.05) from Day 3 (17.5 +/- 5.1 nmol/10(6) cells) to Day 10 (4.8 +/- 1.7 nmol/10(6) cells). Calf serum (5%) in the medium supported greater (p less than 0.05) progesterone production than fetal calf serum (5%) or medium without added serum. Steroidogenic cells did not increase (Days 2-10) in numbers, but increased (p less than 0.01) in mean cell diameter (Day 2, 11.7 +/- 0.4 micron; Day 10, 24.5 +/- 1.6 micron). Steroidogenic capacity on Day 10 of cells cultured Days 2-10 (in vitro) was not different (p greater than 0.05) from that of cells collected from the ovary on Day 10 (in vivo); however, steroidogenic cells recovered from plates had greater (p less than 0.01) mean cell diameters (24.5 +/- 1.6 micron, in vitro, compared to 15.2 +/- 1.0 micron, in vivo). Transmission electron microscopy revealed that cultured cells (Days 5, 10) possessed less smooth endoplasmic reticulum but more lipid droplet inclusions, ribosomes, and rough endoplasmic reticulum than cells obtained in situ (Day 10). Electron-dense secretory granules were rarely seen. Although subcellular morphology of ovine luteal cells in culture was altered, these changes did not appear to significantly affect the ability of these cells to produce progesterone.
...
PMID:Steroidogenic capacity and ultrastructural morphology of cultured ovine luteal cells. 340 46
The objectives of this study were to establish a suitable and validated in vitro bioassay of piscine gonadotropins (GTHs) by using a carp testis androgen production system and to compare the androgenic responses in such an assay to gonadotropins from various vertebrate species. The testes from mature carp with gonadosomatic indices of 8-30% were used. Androgen production was first compared with respect to methods for preparation of the carp testis (sliced, minced, homogenized, and
collagenase
-dispersed testis preparations). The time course of androgen formation, the effects of xanthine and theophylline, and other factors on androgen production also were investigated. Theophylline was more effective than xanthine in potentiation of gonadotropin-evoked androgen formation by carp testis. The testis preparations were incubated in medium 199 (pH 7.40) containing 2 mM theophylline with shaking at 100 cycles/min at 25 degrees C for 4 hr. Homogenized testis preparations had limited ability for androgen production, while sliced, minced, and minced-
collagenase
-dispersed testis preparations were highly responsive to gonadotropins for androgen production. The minced testis preparation, utilizing 100 mg/ml incubation medium per vial, was chosen as the standard incubation procedure in this study. The minced testis androgen production assay was highly sensitive to gonadotropins from several piscine species (silver carp, common carp, and salmon), and all these GTHs produced parallel dose-related androgen production curves. Mammalian GTHs were also capable of promoting androgen formation by carp testis, but they were much less potent than were piscine GTHs. Pregnant mares' serum gonadotropin (PMSG) was more effective than human
chorionic gonadotropin
(hCG) in evoking carp testis androgen production.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Species variation of gonadotropic activity in an in vitro assay measuring androgen formation by carp (Cyprinus carpio) testis with special reference to bioassay of piscine gonadotropins. 377 Apr 34
A sensitive, accurate, and reproducible in vitro bioassay was developed for measuring human
chorionic gonadotropin
(hCG), based on testosterone production by
collagenase
-dispersed interstitial cells of rat testes in response to hCG. The results were compared to those obtained by established beta hCG radioimmunoassay. The assay sensitivity was 25 pg hCG-CR119/ml (65 microIU second IRP/ml). The intra-assay coefficient of variation (CV) was 8.8%, and the interassay CV was 13% and 33% in the high and low ranges of the standard curve, respectively. hCG recoveries were 89.6 +/- 3.12% (SE, n = 12). The pattern of serum bio-hCG followed established patterns of immuno-hCG, with the highest level measured during the first trimester (mean, 52,600 +/- 7,250 SE (mIU/ml, n = 11), decreasing thereafter to a mean value of 7,400 +/- 1,500 mIU/ml at term. The mean ratio of the bio/immunoactivity was consistently greater than one and did not significantly change at the various stages of pregnancy, or between normal and molar pregnancies (first trimester, 1.75 +/- 0.12 SE; midtrimester, 1.46 +/- 0.12; term, 1.50 +/- 0.09; molar, 1.55 +/- 0.2). When serum bioactive and immunoactive hCG were measured in a woman at five weeks of pregnancy, an episodic secretion of hCG was obtained by both assays.
...
PMID:Comparison of human chorionic gonadotropin measurements by radioimmunoassay and in vitro bioassay. 384 Jun 56
Throughout life, the ovarian surface epithelium (OSE) undergoes morphogenetic changes that may be hormonally regulated. To investigate this possibility, a population of cells morphologically identical to native OSE cells was isolated from estrous rabbits with
collagenase
, unit gravity sedimentation, and trypsin-EDTA. Cells were incubated with various concentrations of protein hormones in serum-rich medium or in a chemically defined medium containing fibronectin. Tritiated thymidine was added 24 h before interruption of cultures. Growth-promoting effects of tested hormones were more pronounced and consistent in serum-free cultures. Under these conditions, human
chorionic gonadotropin
(10,000 mIU/ml) caused a 2.8-fold increase in cell number and a 3.4-fold stimulation of thymidine incorporation. Luteinizing hormone (NIAMDD-oLH-24, 1.0 micrograms/ml) and follicle-stimulating hormone (NIADDK-oFSH-16, 1.0 micrograms/ml) produced, respectively, a 1.7-fold and 1.5-fold increase in cell proliferation, and over 1.4-fold and 1.3-fold stimulations of thymidine uptake. When used together, no growth stimulation by these gonadotropins was seen. Slight but significant increases in cell number (1.4-fold) and in radiolabel incorporation (1.3-fold) were observed with prolactin (NIADDK-oPrl-16, 10 ng/ml). These data indicate that some protein hormones promote the growth of OSE cells. This property may be important in regulating these cells during normal and pathologic states.
...
PMID:Growth effects of protein hormones on cultured rabbit ovarian surface epithelial cells. 393 84
A bursa of Fabricius homogenate extract (BHE) was used to investigate the endocrine regulation function of this avian organ. In vivo and in vitro results indicated that BHE inhibited human
chorionic gonadotropin
(HCG)-induced testosterone production by rat testes. Leydig cells from
collagenase
-dispersed rat testes, when treated with BHE, showed a dose-response related depression of testosterone production under HCG stimulation. Young male rats, injected simultaneously with BHE and HCG, failed to show the marked testosterone production peak observed in rats injected with HCG only. However, in vivo treatments with BHE, in the absence of HCG stimulation, did not inhibit basal testosterone production. These results indicate that the bursa of Fabricius produces an endocrine regulation factor that inhibits HCG-induced testosterone production both in vivo and in vitro. Further investigation is necessary to isolate the active factor and determine its mechanism of action.
...
PMID:In vivo and in vitro inhibition of human chorionic gonadotropin-induced testosterone production in rat testis by bursa of fabricius extract. 401 63
In an attempt to justify use of trypsin to achieve more thorough dispersion of luteal cell clumps in vitro, progesterone (P) production by
collagenase
dispersed monkey luteal cells from the mid-luteal phase corpus luteum (CL) was examined in vitro either after 10 min, or continuous (3h) exposure to trypsin (TR). In the first experiment, cells were pre-incubated in TR, then incubated at 37 degrees C for 3h with human
chorionic gonadotropin
(hCG) after the addition of soybean-trypsin inhibitor (STI). Pre-incubation of luteal cells with TR had no effect on the level of P production under basal conditions. Cells that were preincubated with TR responded to hCG stimulation with increased progesterone secretion (P less than 0.01) in a fashion similar to untreated cells. P production in response to hCG was independent of TR concentration over the range of 0.05% to 0.2% during the pre-incubation period. However, continuous exposure (3h) of cells to TR significantly depressed (P less than 0.01) basal P secretion and inhibited the response to hCG. We conclude that TR had no effect on the biopotency of hCG per se, but probably the over-exposure to TR had an adverse effect on the LH/hCG receptors. Addition of STI after a 10 min pre-incubation with TR, prevented these deliterious effects, thereby permitting the use of TR to improve the completeness of luteal cell dissociation.
...
PMID:Progesterone production by dispersed monkey (Macaca mulatta) luteal cells after exposure to trypsin. 624 60
Using a 0-32% continuous metrizamide density gradient, interstitial cells could be separated into five distinct bands. Cells localized in bands 1 (B1), 2 (B2), and 3 (B3) were isolated and incubated for 1h with or without human
chorionic gonadotropin
(hCG). Both B2 and B3 cells responded to hCG with increased cyclic AMP formation, but only B3 cells produced significantly more testosterone. Protein kinase activity of B2 cells was found to be extremely low compared with B1 and B3 cells. Additional treatment of B3 cells with
collagenase
did not cause any change in protein kinase activity. These results indicate that decreased protein kinase activity may be responsible for impaired testosterone synthesis in B2 cells.
...
PMID:Protein kinase activity of purified Leydig cells: low protein kinase activity causes impaired steroidogenesis by band two cells. 628 60
Ten chronically hemiovariectomized cynomolgus and rhesus monkeys were luteectomized 5.5 +/- 0.3 days after the midcycle luteinizing hormone (LH) and follicle-stimulating hormone (FSH) surge in two consecutive cycles. The corpus luteum (CL) was removed, weighed, dispersed with
collagenase
and the luteal cells counted. Luteal cells (50,000/ml) were incubated in Ham's F10 medium for 3 h at 37 degrees C either in the presence or absence of 100 ng/ml human
chorionic gonadotropin
(hCG). Daily blood samples were taken from the monkeys throughout the study for determination of LH, FSH, estradiol (E2) and progesterone levels. Within 5 days following each luteectomy (LX), all monkeys responded with a significant increase in FSH and LH (P less than 0.05). Ovulatory LH/FSH surges occurred 14.4 +/- 0.5 days after the first LX. Hormonal profiles of serum progesterone prior to the first and second LX, CL weight and number of luteal cells/CL were similar (P greater than 0.05). However, luteal cells obtained at the second LX produced more progesterone (P less than 0.05) in vitro under basal and hCG-stimulated conditions than cells from the first LX. The areas under the LH and FSH curves following the first LX were highly correlated (P less than 0.05) with the in vitro progesterone production following the second LX. Thus, the monkeys with the largest areas under the LH and FSH curves subsequently had the highest in vitro progesterone production.
...
PMID:Transitory increases of luteinizing hormone and follicle-stimulating hormone following luteectomy in hemiovariectomized primates significantly increase progesterone secretion in vitro by the subsequent corpus luteum. 643 70
Gossypol (GP) is a natural polyphenolic compound that possesses antifertility and antisteroidogenic activities in both males and females. The dog is highly sensitive to GP toxicity, yet GP's effect on canine testicular steroidogenesis has never been reported. Thus, the present study examines GP's effects on human
chorionic gonadotropin
(hCG)-induced testosterone (T) production by primary cultured canine testicular interstitial cells. After decapsulation and enzymatic dissociation of canine testes in Dulbecco's Modified Eagle Medium with Ham's Nutrient Mixture F-12 (1:1; DME/F-12) containing 0.1%
collagenase
, 0.1% BSA, and 10 micrograms/ml DNase 1 (37 degrees C, 20 min), interstitial cells were isolated by sedimentation and filtration (140 microns) and then cultured in supplemented DME/F-12 medium (5 micrograms/ml insulin, 5 micrograms/ml transferrin, 5 ng/ml sodium selenite; DME/F-12/S) containing 0.1% fetal bovine serum (FBS). FBS was used to enhance cell attachment during the first 24 hours of culture. After 24 hours, the medium was replaced with serum-free DME/F-12/S and the cells were cultured for an additional 24 hours. Thereafter, cells were treated with hCG (0.1 IU/ml) alone and in combination with GP (0.05, 0.5, 2.5 and 5.0 microM). Media were collected for T radioimmunoassay and cells for protein estimation after 8, 16 and 24 hours of treatment. Treatment with hCG significantly (p < 0.05) stimulated T production over that of controls at all treatment times examined. At 8, 16 and 24 hours, T secretion was elevated from 0.91 +/- 0.25, 1.32 +/- 0.42, and 1.41 +/- 0.40 pg/microgram protein to 2.36 +/- 0.50, 2.84 +/- 0.60, and 2.82 +/- 0.43 pg/microgram protein, respectively. At 0.5, 2.5 and 5.0 microM, GP significantly (p < 0.05) reduced hCG-induced T secretion at 16 and 24 hours of treatment to 1.79 +/- 0.50, 1.62 +/- 0.12, 1.34 +/- 0.16 (16 hr), and 1.53 +/- 0.38, 1.43 +/- 0.11, 1.42 +/- 0.32 (24 hr) pg/microgram protein, respectively. At 8 hours, T production was reduced by 2.5 and 5.0 microM GP to 1.08 +/- 0.55 and 0.93 +/- 0.61 pg/microgram protein, respectively. GP, however, did not reduce T production to below basal levels. These results demonstrate the inhibition of hCG-induced T production by GP in cultured canine testicular interstitial cells.
...
PMID:Gossypol inhibits human chorionic gonadotropin-stimulated testosterone production by cultured canine testicular interstitial cells. 882 66
The distribution of gelatinases/matrix metalloproteinases-2 and -9 (MMP-2 and MMP-9) and tissue inhibitor of
metalloproteinase-1
(TIMP-1) in neonatal and gonadotropin-primed immature rat ovaries was studied by immunofluorescent microscopy. Immature female Long-Evans rats were primed with 15 IU pregnant mare's serum gonadotropin (PMSG) in 100 microliters PBS. Two days later, to induce ovulation, the rats were injected with human
chorionic gonadotropin
(hCG, 5 IU/100 microliters PBS). The animals were killed at appropriate times and the ovaries removed and processed for cryostat or paraffin sectioning. Ovaries were also obtained from 7-day-old neonatal rats and processed as above. In the neonatal rat ovary, MMP-2 was present in the follicle and in the ovarian surface epithelium. MMP-9 was not detectable in the neonatal ovary. TIMP-1 was present in the oocyte and in the surface epithelium. In the PMSG-primed ovary, MMP-2 was present in the granulosa and thecal cells of the ovary. MMP-9 distribution, however, was restricted to the interstitial and thecal cells. TIMP-1 was mainly present in the blood vessels and thecal cells, with minor staining in the granulosa cells. In the developing corpus luteum, luteal and endothelial cells were positive for MMP-2. MMP-9 localization was restricted to the plasma membrane of the luteal and interstitial cells. TIMP-1 was clearly observed in the luteal capillaries and, to a lesser extent, in the luteal cell plasma membrane. This distribution of MMP-2, MMP-9, and TIMP-1 in the corpus luteum persisted throughout the life span of the corpus luteum. The spatial and temporal distribution of the gelatinases and TIMP-1 suggests unique roles for these proteins in the rat ovary.
...
PMID:Differential distribution of gelatinases and tissue inhibitor of metalloproteinase-1 in the rat ovary. 977 66
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