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Biomedical subjects

L Hedin

Publications and source records attributed to L Hedin.

53 records · Page 3Linked to original sources
PubMed1987

Tissue distribution and hormonal regulation of messenger ribonucleic acid for regulatory and catalytic subunits of adenosine 3',5'-monophosphate-dependent protein kinases during ovarian follicular development and luteinization in the rat.

cDNA probes specific for the regulatory (R) subunits [RII51; (mol wt, 51,000) and RI (mol wt, 49,000)] and a catalytic (C alpha) subunit of cAMP-dependent protein kinases were used to analyze the hormonal regulation, tissue distribution, and content of mRNAs for these kinase subunits in the rat ovary. Filter hybridization assays demonstrated that mRNA specific for RII51 increased in both thecal and granulosa cells of preovulatory (PO) follicles, then declined precipitously (less than 10-fold) in both cell types within 7 h after an ovulatory (10-IU) dose of hCG and remained low in corpora lutea. Dose-response studies showed that doses of FSH greater than 2 micrograms were required to increase RII51 mRNA in granulosa cells of hypophysectomized (H) rats, whereas doses of 0.5-1.0 micrograms were effective in granulosa cells of H estradiol-treated (HE) rats. At all doses (0.5-50 micrograms) of FSH administered, RII51 mRNA was 4 times higher in granulosa cells of HE rats than in H rats. Solution hybridization assays demonstrated that the concentration of RII51 mRNA increased 6-fold from 20 molecules/granulosa cell in H rats to 120 molecules/cell in H rats treated with estradiol and FSH (HEF). Transcription assays using nuclei of granulosa cells demonstrated further that the 5- to 10-fold increases in RII51 mRNA content in estradiol-/FSH-induced granulosa cells was associated with increased transcription of the RII51 gene. In thecal cells of small antral (SA), PO, and luteinizing follicles, changes in the content of mRNA for RI and C alpha kinase subunits showed a pattern similar to that for RII51. However, in granulosa cells, mRNA specific for RI and C alpha was highest in SA follicles, declined in PO follicles, and remained unchanged during luteinization. The content of mRNA for RI (45-70 molecules/cell) and C alpha (10 molecules/cell) also changed less than 2-fold in granulosa cells of H, HE, and HEF rats. In summary, these results indicate that the content of RII51 mRNA is hormonally regulated in both thecal cells and granulosa cells during follicular development and luteinization. Low concentrations of gonadotropins increase RII51 mRNA, whereas an ovulatory dose of hCG causes mRNA for RII51 to decrease rapidly. In granulosa cells, induction of mRNA for RII51, but not that for RI and C alpha is induced by the actions of estradiol and FSH, and involves increased transcription of the RII51 gene.

Animals↗
PubMed1987

Cholesterol side-chain cleavage P450 messenger ribonucleic acid: evidence for hormonal regulation in rat ovarian follicles and constitutive expression in corpora lutea.

Using an affinity-purified antibody against cholesterol side-chain cleavage P450 (P450scc) and a human P450scc cDNA probe, 11 rat P450scc cDNA clones were identified and isolated from our rat granulosa cell lambda gt11 cDNA expression library. Two clones were plaque purified and subcloned into pBR322. One of these P450scc cDNA clones, approximately 1.2 kilobases (kb) in size, was used as a probe for Northern and filter hybridization assays to analyze the tissue distribution and hormonal regulation of P450scc mRNA in rat ovarian follicles and corpora lutea. Northern transfers revealed a single P450scc mRNA species about 2.0 kb in size. Filter hybridization assays showed that P450scc mRNA was low in granulosa cells and thecal cells of small antral follicles, was increased in both tissues of preovulatory follicles, and was rapidly (within 7 h) and maximally increased (30-fold) during hCG-induced luteinization. P450scc enzyme and mRNA were also elevated in corpora lutea isolated from pregnant rats (days 4-22 of gestation) and rats 1 day after parturition (day 23). The elevation of P450scc enzyme and mRNA was maintained despite the marked decline in serum progesterone concentrations between days 19-22, suggesting that once P450scc mRNA is induced in luteal tissue it may be constitutively expressed. Administering hormones to granulosa cells in culture and to hypophysectomized immature rats in vivo demonstrated that the induction of P450scc mRNA by FSH in granulosa cells was time, dose, and estradiol dependent. High doses of FSH acting on estradiol-primed cells gave the greatest response. The increase in P450scc mRNA in cultured granulosa cells was also stimulated by forskolin and was directly associated with increased synthesis of cAMP and progesterone accumulation. Thus, whereas the induction of P450scc mRNA in granulosa cells was dependent on hormones and cAMP, the maintenance of P450scc mRNA and P450scc protein in corpora lutea appears to involve constitutive expression of P450scc mRNA.

Animals↗
PubMed1987

Prostaglandin endoperoxide synthase in rat ovarian follicles: content, cellular distribution, and evidence for hormonal induction preceding ovulation.

These studies were undertaken to determine if the content of prostaglandin endoperoxide (PGH) synthase (PGS) was regulated in rat ovarian follicles in a time-, tissue-, and dose-dependent manner. For quantitation and localization of the enzyme by immunoblot and immunofluorescent analyses, respectively, a polyclonal antibody to highly purified (95%) ovine seminal vesicle PGS [mol wt, (Mr), 72,000] was generated in a rabbit, and an immunoglobulin G fraction of the antiserum was purified by elution from a PGS affinity resin. Soluble cell extracts were prepared from: 1) small antral (SA) and preovulatory (PO) rat follicles before and at selected time intervals after exposure to increasing doses (0.25-10.0 IU) of hCG, 2) granulosa and thecal cells of these same follicles, and 3) granulosa cells of hypophysectomized (H) rats before and after treatment with estradiol (HE), estradiol and FSH (HEF), and 10 IU hCG. Immunoblot analyses demonstrated that the content of PGS (Mr, 72,000) was low (negligible) in granulosa and thecal cells of SA and PO follicles, was induced preferentially (approximately 15-fold) in granulosa cells between 1 and 7 h after hCG treatment (0.5, 2.0, or 10 IU), and declined between 12-24 h after administration of 10 IU hCG, reaching undetectable amounts in corpora lutea isolated 48 h after hCG treatment. PGS (Mr, 72,000) was also induced by 10 IU hCG in granulosa cells of HEF rats, but was low in granulosa cells of H, HE, and HEF rats. In contrast, prostacyclin synthase was present in granulosa cells of preantral (H and HE rats), SA, and PO follicles, was not induced by hCG, and was highest in thecal cells. Immunofluorescent analyses confirmed both the tissue-specific localization and induction of PGS in granulosa cells of rat PO follicles treated with 10 IU hCG and the subcellular fractionation analyses showing that the PGS that was induced by hCG was localized primarily to a membrane (plasma membrane?) fraction of granulosa cells. Immunofluorescent data also demonstrated immunoreactive PGS in the vascular tissue of the rat corpus luteum but not in the luteal cells. Results of these studies document unequivocally that the synthesis of prostaglandins that is increased by LH/hCG in rats preceding ovulation is associated with an increased PGS content, that induction of the induced enzyme is transient, and that the enzyme is primarily localized to granulosa cell membrane fractions.

Animals↗
PubMed1986

Molecular cloning, cDNA structure, and regulation of the regulatory subunit of type II cAMP-dependent protein kinase from rat ovarian granulosa cells.

One isoform of the regulatory subunit of type II cAMP-dependent protein kinase (R-II51; Mr = 51,000) and its electrophoretic variants (R-II51.5 and R-II52; Mr = 51,500 and 52,000, respectively) are selectively induced by estradiol and follicle-stimulating hormone (cAMP) in rat ovarian granulosa cells. To ascertain the amino acid sequence of R-II51 and to gain insight into the molecular events regulating the intracellular content of ovarian follicular R-II51, we constructed a lambda gt11 cDNA expression library from poly(A)+ RNA of hormone-primed rat granulosa cells. A 1.5-kilobase (kb) cDNA insert, isolated from a plaque-purified R-II antibody positive bacteriophage clone, selectively bound R-II51 mRNA as demonstrated by analysis of the hybrid-selected translation product. Restriction maps and sequence analyses of the 1.5-kb cDNA insert and of the 1.8- and 2.2-kb cDNA inserts from two additional clones showed overlapping sequences which span a region of 3065 nucleotides in size. The 1.5- and 1.8-kb cDNA inserts each contained poly(A) addition signals (1508 and 1761 nucleotides, respectively), terminal poly(A) sequences, and the entire coding region for R-II51 (1204 nucleotides) except for a small number of nucleotides at the 5' end. The 2.2-kb cDNA insert contained 394 nucleotides of the coding region a long 3' untranslated region and two more poly(A) addition signals (3041 and 3059 nucleotides). An amino acid microsequence surrounding the autophosphorylation site of pure rat ovarian R-II51 agreed with the amino acid sequence deduced from the nucleotide sequence of the cDNA. Northern blot analyses demonstrated two major mRNA species (1.8 and 3.2 kb in size) in hormone-primed rat ovaries which were approximately 10- and 50-fold greater than the R-II mRNA content in rat brain and rat heart, respectively. Southern blot analysis of rat liver DNA indicated that a single gene codes for R-II51 mRNA. Structural differences among rat ovarian R-II51, rat heart R-II54, and the known amino acid sequences of bovine R-II and R-I subunits also indicate that the rat ovarian R-II51 subunit is the product of a distinct gene.

Amino Acid Sequence↗
PubMed1986

The neural type II regulatory subunit of cAMP-dependent protein kinase is present and regulated by hormones in the rat ovary.

In this study purified isoforms of rat ovarian regulatory subunit of type II cAMP-dependent protein kinase (R-II) were compared with R-II purified from rat brain. A special neural form of R-II has been previously described in bovine brain. Analysis by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis resolved three isoforms of rat ovarian R-II (R-II54, Mr = 54,000; R-II52, Mr = 52,000; and R-II51, Mr = 51,000) compared to two R-II isoforms in rat brain (R-II54 and R-II52). Polychromatic silver-stained peptide maps of purified R-II subunits indicated that peptides generated from both rat ovarian R-II52 and R-II51 were similar (if not identical) to the peptides of the neural form, R-II52, purified from rat brain. These peptides differed markedly from those generated from R-II54 of either rat ovary, brain, or heart. Ovarian R-II52/51 photoaffinity labeled with 8-N3-[32P]cAMP and analyzed by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis was shown to consist of three (rather than two) isoelectric variants, which were similar to three variants resolved from rat brain R-II and clearly distinct from that of rat heart R-II54. An antibody which recognized both the R-II54 and R-II52/51 isoforms of rat ovarian extracts also recognized both forms of rat brain R-II (R-II54 and R-II52) and similar forms in extracts of rat adrenal and parotid glands. These results strongly suggest that the R-II52 isoform previously designated as a neural specific form of R-II is present in high concentrations in a nonneural tissue, the rat ovary.

Animals↗
PubMed1986

Differentiation of rat ovarian thecal cells: evidence for functional luteinization.

To determine if thecal cells of rat preovulatory (PO) follicles become functionally luteinized, theca from small antral (SA) and PO follicles were isolated before and 8 h after iv injection of an ovulatory dose (10 IU) of hCG. Thecal explants were cultured for 30 days in Dulbecco's Modified Eagle's Medium-Ham's F-12 medium containing 1% fetal calf serum (FCS) with or without 5 ng/ml ovine LH or 10 microM forskolin. Whereas theca from SA, hCG-treated SA, and PO follicles were dependent on LH or forskolin to maintain progesterone (greater than 10 ng/ml) and androstenedione (greater than 10 ng/ml) accumulation, luteinizing theca (hCG-treated PO) accumulated more than 10 ng/ml progesterone and more than 2 ng/ml androstenedione with or without LH or forskolin for 30 days. Granulosa cells were isolated from these same follicles and cultured under similar conditions, including 10 ng/ml testosterone and 25 ng/ml ovine FSH. Only granulosa cells isolated from luteinizing follicles (hCG-treated PO) maintained progesterone (greater than 20 ng/ml) and estradiol (10 ng/ml) accumulation with or without FSH or forskolin for 30 days. Basal concentrations of cAMP were 5 to 10-fold higher in thecal and granulosa cells from luteinizing follicles than in these tissues isolated from SA or PO follicles. We conclude that thecal cells as well as granulosa cells of rat PO follicles respond to the LH/hCG surge by becoming functionally luteinized, less dependent on LH, and capable of maintaining an increased accumulation of basal cAMP. Furthermore, the data suggest that one luteinizing thecal explant produces a similar amount of progesterone as one follicle equivalent of luteinizing granulosa cells. Thus, luteinized theca have the potential of contributing significantly to progesterone secretion by the mature rat corpus luteum.

Androstenedione↗
PubMed1986

The role of cyclic adenosine 3',5'-monophosphate in the ovulatory process of the in vitro perfused rabbit ovary.

LH alters ovarian steroidogenesis via adenylate cyclase (AC) activation and cAMP production. Although LH also initiates ovarian follicle rupture, evidence is lacking for involvement of cAMP in this process. This work explores the involvement of cAMP in the ovulation of in vitro perfused rabbit ovaries by comparing LH stimulation of ovaries with that of LH plus 3-isobutyl-1-methyl-xanthine (IBMX), (an inhibitor of phosphodiesterase) and of forskolin (a nonreceptor-specific activator of AC). Venous perfusates were analyzed for cAMP, progesterone, 17 beta-estradiol, and testosterone, ovaries were analyzed for cAMP, and ovulations were noted. LH, LH plus IBMX, and forskolin all increased tissue cAMP levels significantly after 0.5 h, the perfusate levels increasing rapidly thereafter reaching plateau levels, while tissue levels returned to control levels after 2.4 h. LH plus IBMX and forskolin significantly increased cAMP release over LH controls, LH plus IBMX increasing and forskolin decreasing the number of ovulations. Forskolin significantly increased progesterone release over LH controls and, although no other significant steroid differences were seen, strong tendencies existed. Although forskolin could induce ovulations and could induce significantly higher release of cAMP than LH, it resulted in a lower ovulation rate than receptor-specific LH. LH plus IBMX also induced significantly higher cAMP release than LH, as did forskolin, and resulted in a higher ovulation rate than both LH and forskolin. These findings suggest, not only that cAMP production alone is sufficient for ovulation, but also that the receptor specificity of the cAMP production is important for the number of ovulations. Since tissue levels of cAMP peak several hours before ovulation, the cAMP is probably inducing a metabolic pathway leading to ovulation.

1-Methyl-3-isobutylxanthine↗
PubMed1985

Purification and characterization of hormone-regulated isoforms of the regulatory subunit of type II cAMP-dependent protein kinase from rat ovaries.

The regulatory subunit (R-II) of cAMP-dependent protein kinase type II is induced in rat ovarian granulosa cells by the synergistic actions of estradiol and follicle-stimulating hormone. The R-II from rat ovaries was compared with R-II from rat heart, rat brain, bovine heart, and bovine brain using immunological methods, 8-N3[32P]cAMP photoaffinity labeling and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Three isoforms of R-II were identified in rat ovarian cell extract (R-II54 Mr = 54,000, R-II52 Mr = 52,000, R-II51 Mr = 51,000), two isoforms of R-II in rat brain cell extract (Mr = 54,000, Mr = 52,000), and one isoform of R-II in rat heart cell extract (Mr = 54,000). Rat ovarian R-II54, heart R-II, and brain R-II (Mr = 54,000) were recognized by antiserum against rat heart R-II, whereas rat ovarian R-II52/R-II51 and rat brain R-II (Mr = 52,000) were not. In contrast, an antiserum raised against bovine heart R-II recognized all three isoforms of ovarian R-II as well as the lower molecular weight form of rat brain R-II. Ovarian types R-II52 and R-II51 but not R-II54 were increased selectively in granulosa cells by estradiol and follicle-stimulating hormone. In addition: 1) ovarian R-II52/51 subunits were purified to homogeneity and shown to recombine with C subunit from bovine heart to form a cAMP-dependent protein kinase; 2) pure R-II52/51 were not interconvertible to a higher molecular weight form by C subunit-dependent phosphorylation; 3) pure rat heart R-II (Mr = 54,000) and ovarian R-II52/51 exhibited distinct differences based on one- and two-dimensional peptide mapping; and 4) by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis pure R-II52/51 were resolved as three (rather than two) isoelectric variants which were clearly different from pure rat heart R-II54. Thus, the hormone-regulated form of R-II in rat ovarian granulosa cells appears to represent a gene product distinct from R-II54 in rat heart.

Affinity Labels↗
PubMed1985

Comparison between the steroidogenic responses after pulsatile and continuous administration of gonadotrophin releasing hormone to superfused rat follicles.

Gonadotrophin releasing hormone (GnRH) exhibits both stimulatory and inhibitory effects on the ovarian tissue in the rat. For the action of GnRH on the pituitary, the mode of administration is of utmost importance. The binding characteristics and regulation of the GnRH receptors found in the ovary are very similar to those of the pituitary. The aim of the present study was to compare the steroidogenic response of superfused, preovulatory rat follicles to continuous and pulsatile administration of a GnRH analogue (GnRHa). The results obtained with a single pulse of luteinizing hormone (LH) served as a control. Repeated pulses (1 pulse X h-1) or continuous administration of GnRHa was found to be more effective than a single pulse of GnRHa. The effect of GnRHA, irrespective of the mode of administration, was most pronounced on the secretion of 20 alpha-OH-progesterone (20 alpha-OHP). Also the release of testosterone (T) and oestradiol (E2) was stimulated but to a lesser extent. In comparison to LH, the GnRHa response was delayed and without detectable release of cyclic AMP (cAMP). These results illustrate that pulses of GnRH stimulate the steroidogenesis in preovulatory follicles. In contrast to the effects of GnRHa on the pituitary, the modes of administration seem to be of less importance for the stimulation of the rat ovary.

20-alpha-Dihydroprogesterone↗
PubMed1984

Effect of gonadotrophin releasing hormone upon the pattern of steroidogenesis in isolated preovulatory rat follicles.

The effects of GnRH and a potent GnRH analogue (D-Ala6-des-gly-NH2-GnRH-ethylamide) on steroidogenesis in isolated preovulatory follicles of PMSG-treated immature rats were examined in short-term incubations and compared to the effect of LH. Steroids were analyzed by RIA. GnRH stimulated the accumulation of pregnenolone (2-fold), progesterone (4-fold), 20 alpha-OH-progesterone (38-fold), androstenedione (4-fold), testosterone (3-fold), and oestradiol-17 beta (2-fold) during a 6 h incubation. The time-course of stimulation was the same for each of the steroids analyzed, with a significant effect at 4 and 6 h, but not at 2 h of incubation. Dose-response curves were similar for each steroid, and the GnRH analogue and GnRH gave parallel curves with minimal effective concentrations being 1 and 10 ng/ml, respectively. The stimulatory effect of LH was more pronounced and rapid (2 h) than that of GnRH. During prolonged incubation (6-8 h) with GnRH or LH there was evidence for an inhibition of testosterone production, probably due to suppression of the C21-side chain cleavage enzyme. Thus, the qualitative response to GnRH on follicular steroidogenesis resembled that of LH in some but not all respects. The differences in time-course and maximal steroid secretion between GnRH and LH are compatible with different mechanisms of action in the follicle.

17-alpha-Hydroxyprogesterone↗
PubMed1983

Involvement of cyclic AMP and protein synthesis in the desensitization of the prepubertal rat ovary.

Luteinizing hormone (LH) stimulates cyclic AMP (cAMP) production in ovarian cells. After the initial stimulation there is a development of refractoriness (desensitization) to a subsequent LH stimulation. The present investigation was designed to study the role of cAMP in this desensitization process and the influence of protein-synthesis inhibitors. Ovaries from 23-day-old rats were preincubated in buffer, dibutyryl-cAMP, 8-bromo-cAMP or LH. After a washing period in buffer, the ovaries were incubated in the presence of LH. Those ovaries preexposed to the cAMP analogues showed a reduced cAMP-production to LH. This reduction was found to be both dose- and time-dependent, but was never as marked as after preincubation with LH. Desensitization developed more slowly after preincubation with cAMP than with LH. Inhibitors of protein synthesis (puromycin, cycloheximide) completely abolished the cAMP-induced desensitization but only partially prevented the LH-induced desensitization. These results show that processes, dependent and independent of cAMP, are involved in the desensitization after LH stimulation of the prepubertal rat ovary.

1-Methyl-3-isobutylxanthine↗
PubMed1983

Forskolin effects on the cAMP system and steroidogenesis in the immature rat ovary.

The diterpene forskolin was found to activate the adenylate cyclase system in intact tissue and membrane preparations of the immature rat ovary. The cyclic AMP (cAMP) response reached a maximal level after 5 min and no decline was observed even after 4 h of incubation. Forskolin stimulated production of both progesterone and testosterone in a pattern similar to that produced by luteinizing hormone (LH) or dibutyryl-cAMP (dbcAMP). In combination with LH, follicle-stimulating hormone (FSH) or prostaglandin E2 (PGE2), forskolin potentiated the hormone effects on adenylate cyclase activity in membrane preparations. Pretreatment with LH or PGE2 desensitized the cells to further hormone stimulation, while the forskolin response was unaffected. Pre-exposure to forskolin did not desensitize the cells to a subsequent stimulation by LH or PGE2. The presence of 8-bromo-cAMP (brcAMP) in the preincubation medium reduced the subsequent hormone response. These results demonstrate a rapid and sustained activation of the adenylate cyclase system by forskolin in the rat ovary. The steroidogenic response was similar to that of known stimulators of ovarian cells (LH, dbcAMP). The inability of forskolin to induce desensitization of the adenylate cyclase system demonstrates, however, important differences between hormone and non-hormone activation. Consequently, forskolin can be a useful tool for investigation of the mechanisms involved in the desensitization process.

Adenylyl Cyclases↗
PubMed1983

Dose-related effects of luteinizing hormone on the pattern of steroidogenesis and cyclic adenosine monophosphate release in superfused preovulatory rat follicles.

The secretion of steroids and the release of cAMP in response to repeated luteinizing hormone (LH) stimulation were examined during superfusion of isolated preovulatory rat follicles. A high dose of ovine LH (1 microgram/ml for 20 min) caused a prolonged increase in the secretion of progesterone (P) and 20 alpha-dihydroprogesterone (20 alpha-OHP) and a transient increase in the secretion of testosterone (T) and estradiol-17 beta (E2), and was accompanied by a peak of cAMP release. A single pulse of LH at a low dose level (10 mg/ml for 20 min) gave a limited increase in T secretion, but no clear change in P, 20 alpha-OHP and E2 secretion or cAMP release. When the follicles were challenged with a second pulse of LH (at 1 microgram/ml), the response varied according to the dose of LH delivered in the preceding pulse. Following exposure to the high dose of LH, the follicles were partially refractory to the second LH challenge in terms of cAMP and P and the secretion of T and E2 remained low. The low dose of LH, however, had a conditioning effect on the follicles since the response to the second LH challenge was amplified in terms of P, 20 alpha-OHP and cAMP. In this case a secondary increase in T and E2 secretion was found. The differential response to varying doses of LH are likely to reflect the physiological control of steroidogenesis during final follicular maturation.

20-alpha-Dihydroprogesterone↗
PubMed1983

Gonadotrophins stimulate lactate production by rat cumulus and granulosa cells.

Oocyte-cumulus complexes and mural granulosa cells, respectively, isolated from pre-ovulatory rat follicles and cultured in lactate-free medium showed a continuous accumulation of lactate during a 1 to 7 h incubation. Lactate production was stimulated by gonadotrophins, both when administered in vivo and in vitro, with the exception that LH given in vivo did not affect granulosa cell lactate production. Since the oocyte is known to have specific demands on energy substrate, it is suggested that the lactate produced is important for the growing and maturing oocyte.

Animals↗
PubMedDate not supplied

Role of cyclooxygenase-2 for fluid secretion by the inflamed gallbladder mucosa.

Inflammatory fluid secretion by the gallbladder mucosa in experimental cholecystitis is induced by activation of cyclooxygenase, which leads to an increase in prostaglandin formation. Cyclooxygenase exists as a constitutive (cyclooxygenase-l) and an inducible (cyclooxygenase-2) isoform. The aim of this study was to demonstrate the role of cyclooxygenase-2 in inflammatory fluid secretion of the feline gallbladder. Experiments were performed 10 weeks after a surgical procedure in which chronic cholecystitis was induced in cats by ligation of the cystic duct and implantation of a gallstone in the gallbladder. Gallbladder fluid transport was continuously monitored via a perfusion system. In inflammed gallbladders the continuous fluid secretion was reversed to absorption by intravenous injection of the selective cyclooxygenase-2 blocker, NS 398 (P <0.001). Increased levels of the inducible cyclooxygenase-2 were shown by immunoblotting in inflamed gallbladders. Selective pharmacologic blockage of cyclooxygenase-2 reduced the prostaglandin E2 release to the inflamed gallbladder lumen (P <0.01). These data suggest that cyclooxygenase-2 is involved in the inflammatory response during chronic cholecystitis. Selective cyclooxygenase-2 blockers may offer an alternative to traditional nonsterodial anti-inflammatory drugs with fewer side effects in patients with cholecystitis who are awaiting operation.

Animals↗
PubMedDate not supplied

Higher levels of soluble E-cadherin in cyst fluid from malignant ovarian tumours than in benign cysts.

A major diagnostic dilemma in the clinical gynaecological oncology setting is to preoperatively determine whether a complex ovarian mass is benign or malignant. The cell-cell adhesion molecule E-cadherin has previously been localised in biopsies from both benign and malignant epithelial ovarian tumours. In this study, soluble E-cadherin levels was measured with ELISA-technique in peripheral blood, ascites and cystic fluids from patients (n = 33) undergoing surgery for ovarian cystic masses. The levels of soluble E-cadherin were significantly higher in cystic fluid from cystadenocarcinomas (p < 0.001) and borderline tumours (p < 0.05) as compared to cystic fluid from cystadenomas. In ascites fluid and peripheral blood no significant differences were seen. However, ratios of cystic fluid/peripheral blood levels were significantly higher in cystadenocarcinoma (p < 0.001) and borderline tumours (p < 0.05) as compared to benign tumours. In conclusion, measurements of soluble E-cadherin in cystic fluid from patients presenting with complex ovarian masses may be beneficial in increasing the accuracy of preoperative diagnosis.

Adenocarcinoma↗