RESUMO
The transcription factor FoxP2 is related to acoustic communication in vertebrates and, although widely expressed in various tissues, its mutations cause a speech disorder in humans and disrupt vocalization in mice. In honeybee colonies, workers transmit information about a food location using 'dance communication', which is a form of acoustic communication. We identified a honeybee FoxP2-homologue, AmFoxP, and investigated its expression in the honeybee brain to elucidate its possible role in dance communication. The relative abundance of AmFoxP mRNA in the worker brain increased during the first 4 days of adult life. In situ hybridization revealed AmFoxP expression around the optic lobes, central complex, dorsal lobes, and protocerebral lobes, which was not dependent on the caste or division of labour.
Assuntos
Abelhas/metabolismo , Encéfalo/metabolismo , Fatores de Transcrição Forkhead/biossíntese , Sequência de Aminoácidos , Animais , Sequência de Bases , Abelhas/genética , Clonagem Molecular , Feminino , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica no Desenvolvimento , Hibridização In Situ , Masculino , Dados de Sequência Molecular , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Técnica de Amplificação ao Acaso de DNA Polimórfico , Alinhamento de SequênciaRESUMO
Gonadotropin-releasing hormone (GnRH) and its agonist analog (GnRHa) are well known to have luteolytic effects. We previously reported that prolactin (PRL) stimulated matrix metalloproteinase (MMP)-2 activity to degrade collagen type IV as a mechanism of structural luteolysis. The effects of GnRHa treatment on developed corpora lutea are unknown. In this study we assessed the effect of GnRH on MMP expression and induction of structural involution of developed corpora lutea of superovulated rats using GnRHa. Pregnant mare serum gonadotropin-human chorionic gonadotropin (hCG)-synchronized ovulation and luteinization were induced in immature female rats, followed by daily treatment with GnRHa from 5 days after hCG treatment. GnRHa-induced involution of corpora lutea was evident 3 days after the treatment, as shown by their markedly smaller size (60% of the control weight). Nine days after hCG injection, serum progesterone and 20alpha-dihydroprogesterone concentrations were as low as those associated with structural luteolysis. These findings revealed that GnRHa has the ability to induce structural luteolysis in superovulated rats in the same way that PRL does. To gain information on mechanisms of luteal involution induced by GnRHa, we performed gelatin zymography. This showed a significant increase in the active form of MMP-2 in the luteal extract of GnRHa-treated rats (more than twofold that of the control). Activation of pro-MMP-2 by membrane type-MMP (MT-MMP) is reported to be a rate-limiting step for catalytic function. Another function of MT-MMP is to degrade collagen types I and III. The plasma membrane fraction of corpora lutea of GnRHa-treated rats activated pro-MMP-2 of fetal calf serum, resulting in a marked shift of the 68-kDa band to the 62-kDa band in the zymogram. A Northern hybridization study also revealed simultaneous significant increases in expression of MMP-2 mRNA and MT1-MMP mRNA in corpora lutea of GnRHa-treated rats (more than threefold the control level). In summary, hormonal and histological features of corpora lutea of GnRHa-treated superovulated rats correspond to those of structural luteolysis. GnRHa stimulated the expression of MMP-2 and MT1-MMP in developed corpora lutea associated with involution. These findings support the conclusion that MMP-2, activated by MT1-MMP, and MT1-MMP itself, remodel the extracellular matrix during structural luteolysis induced by GnRHa.
Assuntos
Colagenases/metabolismo , Corpo Lúteo/enzimologia , Gelatinases/metabolismo , Hormônio Liberador de Gonadotropina/agonistas , Leuprolida/farmacologia , Luteólise , Metaloendopeptidases/metabolismo , Análise de Variância , Animais , Northern Blotting , Western Blotting , Corpo Lúteo/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Ativação Enzimática , Feminino , Metaloproteinase 1 da Matriz , Metaloproteinase 2 da Matriz , Ratos , Ratos Sprague-Dawley , SuperovulaçãoRESUMO
We evaluated the usefulness of the newly defined Doppler index combining systolic and diastolic myocardial performance, in assessing right-heart dysfunction in 29 patients with chronic respiratory failure caused by old tuberculosis who were on 24-h home oxygen therapy. We measured tricuspid inflow velocity, right-ventricular outflow velocity, late/early diastolic peak velocities (A/E), the ratio between pre-ejection period and ejection time (PEP/ET), and the new index of systolic and diastolic myocardial performance (SDMP) calculated as (isovolumetric contraction time + isovolumetric relaxation time)/ejection time. The calculated A/E, PEP/ET and SDMP in our patients were significantly higher than those in age-matched healthy subjects (n = 37, mean age 67 +/- 8 years). There was no overlap in the SDMP index between healthy subjects and patients and the index was not influenced by heart rate. Our results suggest that SDMP index is a better marker than A/E and PEP/ET for the assessment of right-ventricular impairment.
Assuntos
Serviços de Assistência Domiciliar , Oxigenoterapia , Insuficiência Respiratória/complicações , Insuficiência Respiratória/terapia , Disfunção Ventricular Direita/complicações , Idoso , Doença Crônica , Ecocardiografia Doppler , Feminino , Coração/fisiopatologia , Testes de Função Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência Respiratória/fisiopatologia , Tuberculose Pulmonar/complicações , Disfunção Ventricular Direita/fisiopatologiaRESUMO
A 47-year-old woman was thirdly admitted to our hospital for therapy to multi-drug resistant tuberculosis of the lung in June 88. Although she was treated with TH, PAS and EVM, M. tuberculosis were positive constantly in her sputum. She complained of sleep disturbance, irritability, headache on September 89, she was diagnosed reactive depression. But her symptoms were progressive, low level of intelligence test in November, apatic in December and became spastic paralysis and vegetable state at next year. She was died of pneumonia in November 90. Her autopsy findings showed no brain atrophy nor meningitis. Microscopically, central chromatolysis were showed in Betz cells and anterior horn cells, these findings sometimes suspected for Peragulla, but we could not obtained definite pathological diagnosis, because we could not have been obtained findings indicating for Peragulla. Finally, we reported the clinical course and autopsy findings of dementia occurred during therapy for multi-drug resistant pulmonary tuberculosis.
Assuntos
Demência/etiologia , Tuberculose Resistente a Múltiplos Medicamentos/complicações , Tuberculose Pulmonar/complicações , Demência/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade , Tuberculose Resistente a Múltiplos Medicamentos/terapia , Tuberculose Pulmonar/terapiaRESUMO
The usefulness of MTD (Amplified Mycobacterium Tuberculosis Direct Test) for a rapid diagnosis of tuberculosis was evaluated. A total of 400 clinical samples obtained from July, 1995 to June, 1997 were tested by MTD, direct microscopy and culture. The results of MTD and smear/culture were coincident in 387 out of 400 samples. Eight samples (2%) were MTD false-positive (i.e. they were MTD positive but smear and culture negative), and 5 (1.25%) were MTD false-negative (i.e. MTD negative but smear and/or culture positive). Despite a careful review of the clinical data of those patients whose samples showed discrepant results, the reasons of discrepancy were not clear in 2 (0.5%) of the 8 false positives and 3 (0.75%) of the 5 false negatives. In the other cases, the MTD false positives may be accounted for the presence of previous M. tuberculosis infection, the influence of anti-tuberculous medication and so on, and the MTD false negatives are most likely due to the presence of inhibitors (blood, for example) or to the small number of organisms in the specimens. It can be concluded that adequate samples should be obtained, and that MTD should be repeated in case of discrepant results.
Assuntos
Técnicas Bacteriológicas , Mycobacterium/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico , Tuberculose/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tuberculose/microbiologiaRESUMO
Bronchial hypersensitivity was investigated by astograph in 25 nasal allergy patients without clinical symptoms of asthma and 103 healthy people from 20 asthmatic families. The data were compared with those obtained from 36 asthmatics. Intradermal skin tests and HLA typing were also performed on the members of asthmatic families. Bronchial hypersensitivity was present at a much higher rate in nasal allergy patients than in healthy people. It was also demonstrated that bronchial hypersensitivity was present even in non-asthmatics from asthmatic families, and the incidence of bronchial hypersensitivity tended to increase when complicated by nasal allergy. Increased bronchial hypersensitivity was shown in people from asthmatic families with positive skin tests to mites and house dust. Bronchial hypersensitivity seemed to be related to HLA-haplotype in the same family. The results of antigen sensitization as measured by intradermal skin reaction test suggested that hereditary factors play some role in the development of bronchial hypersensitivity.
Assuntos
Asma/imunologia , Brônquios/imunologia , Hipersensibilidade/imunologia , Rinite Alérgica Sazonal/imunologia , Adolescente , Adulto , Idoso , Asma/genética , Criança , Antígenos HLA/genética , Humanos , Hipersensibilidade/genética , Pessoa de Meia-Idade , Rinite Alérgica Sazonal/genéticaRESUMO
Asthmatic symptoms are worsened after drinking small amounts of alcoholic beverages in Japanese asthmatic patients. Our previous results showed that the ingestion of pure ethanol caused a fall in FEV1.0 in about half of the Japanese asthmatics we studied. We studied the inhibitory effects of pretreatment with three kinds of anti-asthmatic agents on ethanol-induced bronchoconstriction in six Japanese asthmatic patients. We tested oral cyproheptadine hydrochloride (8 mg), which is an anti histamine agent, inhaled disodium cromoglycate (2 mg), which has an inhibitory effect on the release of chemical mediators from mast cells, and inhaled atropine sulfate (3 mg), which is an anti-cholinergic agent. Pretreatment with cyproheptadine significantly inhibited the fall in FEV1.0 120 minutes after ethanol challenge (p less than 0.05). Inhaled DSCG had significant inhibitory effects on the fall in FEV1.0 15 and 30 minutes after ethanol challenge (p less than 0.05). Inhaled atropine had no inhibitory effect. These results suggest that histamine, released from mast cells, plays an important role in ethanol induced bronchoconstriction in Japanese asthmatic patients.
Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Asma/tratamento farmacológico , Atropina/uso terapêutico , Broncoconstrição/efeitos dos fármacos , Cromolina Sódica/uso terapêutico , Ciproeptadina/uso terapêutico , Etanol/antagonistas & inibidores , Adulto , Idoso , Asma/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The efficacy of an intravenous 5-HT3 antagonist (granisetron) and four oral 5-HT3 antagonists (granisetron, ondansetron, tropisetron and ramosetron) on chemotherapy-induced emesis were investigated in 21 gynecologic cancer patients (63 courses). The severity of emesis after chemotherapy was classified in 4 grades (0: none, 1: slight loss of appetite, 2: severe loss of appetite, but tolerable, and 3: untolerable). The effect of 5-HT3 antagonists was judged by both the score for the severity of the emesis and the frequency of vomiting. The four oral 5-HT3 antagonists were almost the same in efficacy for 5 days after chemotherapy. Oral 5-HT3 antagonists were almost equipotent to intravenous granisetron for JT (paclitaxel + carboplatin) therapy or T (paclitaxel) therapy for 5 days after chemotherapy. However, they were ineffective for CAP (cisplatin + adriamycin + cyclophosphamide) therapy. From these results, oral 5-HT3 antagonists were proved to have a sufficient anti emetic effect after chemotherapy in cases of JT or T therapy. However, in cases of CAP therapy, intravenous 5-HT3 antagonists were thought to be preferable for the control of emesis due to chemotherapy.
Assuntos
Antieméticos/uso terapêutico , Benzimidazóis/uso terapêutico , Neoplasias dos Genitais Femininos/tratamento farmacológico , Granisetron/uso terapêutico , Indóis/uso terapêutico , Náusea/prevenção & controle , Ondansetron/uso terapêutico , Antagonistas da Serotonina/uso terapêutico , Vômito/prevenção & controle , Administração Oral , Carboplatina/efeitos adversos , Cisplatino/efeitos adversos , Ciclofosfamida/efeitos adversos , Doxorrubicina/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Pessoa de Meia-Idade , Paclitaxel/efeitos adversos , TropizetronaRESUMO
Paclitaxel is one of the most commonly used anti-neoplastic drugs for the treatment of solid tumors. Unfortunately, its use is often associated with dose-limiting painful peripheral neuropathy and subsequent neuropathic pain that is resistant to standard analgesics. However, there are few clinically available drugs or drug classes for the treatment of paclitaxel-induced neuropathy due to a lack of information regarding the mechanisms responsible for it. In this study, we examined the involvement of l-serine in paclitaxel-induced hyperalgesia/allodynia and decrease in sensory nerve conduction velocity (SNCV). We used a preclinical rat model of paclitaxel-induced painful peripheral neuropathy. Response to von Frey filaments, SNCV, 3-phosphoglycerate dehydrogenase (3PGDH) expression, and l-serine concentration were examined. Effects of l-serine administration were also investigated. Paclitaxel treatment induced mechanical allodynia/hyperalgesia and reduction of SNCV. Paclitaxel also decreased the l-serine concentration in the dorsal root ganglion (DRG) but not in the sciatic nerve or spinal cord. In addition, paclitaxel decreased expression of 3PGDH, a biosynthetic enzyme of l-serine, in the DRG. Immunohistochemistry showed that 3PGDH was localized in satellite cells but not in neurons in the DRG. Intraperitoneal administration of l-serine improved both paclitaxel-induced mechanical allodynia/hyperalgesia and the reduction of SNCV. These results suggest that satellite cell-derived l-serine in the DRG plays an important role in paclitaxel-induced painful peripheral neuropathy. These findings may lead to novel strategies for the treatment of paclitaxel-induced painful peripheral neuropathy.
Assuntos
Antineoplásicos Fitogênicos/efeitos adversos , Gânglios Espinais/metabolismo , Paclitaxel/efeitos adversos , Dor/metabolismo , Doenças do Sistema Nervoso Periférico/metabolismo , Células Satélites Perineuronais/metabolismo , Serina/biossíntese , Animais , Temperatura Baixa , Hiperalgesia/induzido quimicamente , Hiperalgesia/metabolismo , Hiperalgesia/fisiopatologia , Masculino , Condução Nervosa , Dor/induzido quimicamente , Dor/fisiopatologia , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/fisiopatologia , Fosfoglicerato Desidrogenase/biossíntese , Ratos , Ratos Sprague-Dawley , Serina/química , Serina/farmacologia , Estereoisomerismo , Cauda/inervação , TatoRESUMO
We present a case of polycystic ovary syndrome (PCOS) that developed simultaneous intra- and extra-uterine pregnancy with ovarian hyperstimulation syndrome (OHSS) after induction of ovulation with pure FSH-HCG. At 9 weeks of pregnancy, the bilateral tubal pregnancy caused an imminent spontaneous abortion, and both Fallopian tubes were resected. After the laparotomy, the pregnancy progressed without problems until 31 weeks and 5 days of pregnancy, when signs of spontaneous abortion appeared, and healthy twin female babies were delivered by cesarean section. The incidence of heterotopic pregnancy is increasing in cases in which inducers of ovulation or ART, such as IVF-ET and GIFT, have been employed. One must be well aware that the danger of heterotopic pregnancy following induction of ovulation is imminent, particularly in cases with risk factors of multiple and/or extra-uterine pregnancy, such as PCOS, a history of tubal restoration, and sexually transmitted disease(s).
Assuntos
Síndrome de Hiperestimulação Ovariana/complicações , Indução da Ovulação , Síndrome do Ovário Policístico/complicações , Gravidez Tubária/complicações , Adulto , Feminino , Humanos , Gravidez , Gravidez Múltipla , GêmeosRESUMO
A case of a sclerosing stromal tumor (SST) of the ovary is presented. One of the tumor's characteristics was its high vascularity. On immunohistochemical staining, the vascular endothelial growth factor (VEGF) was positive for both cellular and edematous areas in the tumor. VEGF was thought to be a factor that affected the clinicopathological features of this tumor.
Assuntos
Fatores de Crescimento Endotelial/biossíntese , Linfocinas/biossíntese , Neoplasias Ovarianas/metabolismo , Tumores do Estroma Gonadal e dos Cordões Sexuais/metabolismo , Fator VIII/análise , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Neoplasias Ovarianas/irrigação sanguínea , Neoplasias Ovarianas/patologia , Tumores do Estroma Gonadal e dos Cordões Sexuais/irrigação sanguínea , Tumores do Estroma Gonadal e dos Cordões Sexuais/patologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio VascularRESUMO
We have experienced case involving a 63-year-old patient with a pulmonary carcinoma, who was given an enterectomy following a lobectomy, due to minimal intestinal metastasis. In this case, using flow cytometry, the cancer cell nuclear DNA content was analyzed for the primary tumor focus, the mediastinal lymph node metastatic focus, and the small intestinal metastatic focus. For the primary focus, a cancer cellular population of polyploidy with 2 ploidies of DNA content was observed, while for both the metastatic foci, only a single cancer cellular population was observed, indicating the heterogeneity of the nuclear DNA content between the primary focus and metastatic foci. These 2 metastatic foci had DNA contents completely corresponding to that for a ploidy with a high DNA content in the primary focus, suggesting a metastasis of only the above population from the primary focus. The present case apparently formed metastatic foci in other organs than the lungs but only by cancer cells more susceptible to metastasis among the cancer cells found in the primary focus.
Assuntos
DNA de Neoplasias/análise , Neoplasias Intestinais/secundário , Neoplasias Pulmonares/genética , Aneuploidia , Núcleo Celular/análise , Citometria de Fluxo , Humanos , Neoplasias Intestinais/análise , Neoplasias Intestinais/genética , Intestino Delgado , Neoplasias Pulmonares/análise , Neoplasias Pulmonares/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , PoliploidiaRESUMO
In rat luteal cells labeled with [3H]oleic acid, PGF2 alpha-stimulated phospholipase D (PLD) activation was investigated. The PLD activity was detected by measuring the accumulation of [3H]phosphatidylethanol (PtdEt) in the presence of ethanol. PGF2 alpha stimulated PtdEt accumulation at concentrations of more than 100 nM in the presence of ethanol. However, PtdEt accumulation did not change in the absence of ethanol. PGF2 alpha (1 microM) increased PtdEt accumulation after 1 min, and the accumulation reached a plateau by 2-3 min. These results indicate that PGF2 alpha activates PLD in rat luteal cells. U-73122, a phospholipase C (PLC) inhibitor, and staurosporine, a protein kinase C (PKC) inhibitor, did not inhibit PGF2 alpha-stimulated [3H]PtdEt accumulation. These results suggest that PGF2 alpha-induced PLD activation is different from PLC-PKC systems. We reported previously that PGF2 alpha stimulated the release of arachidonic acid. The effects of indomethacin, nordihydroguaiaretic acid (NDGA), and 5,8,11,14-eicosatetraynoic acid (ETYA), inhibitors of arachidonic acid metabolism, on PGF2 alpha-stimulated PtdEt accumulation were examined. Pretreatment with indomethacin enhanced PGF2 alpha-induced PtdEt accumulation. In contrast, pretreatment with NDGA and ETYA inhibited PGF2 alpha-induced PtdEt accumulation. It is suggested that PGF2 alpha-stimulated PLD activation is mediated via lipoxygenase products.
Assuntos
Ácido Araquidônico/antagonistas & inibidores , Dinoprosta/farmacologia , Glicerofosfolipídeos , Células Lúteas/enzimologia , Fosfolipase D/metabolismo , Ácido 5,8,11,14-Eicosatetrainoico/farmacologia , Animais , Inibidores de Ciclo-Oxigenase/farmacologia , Ativação Enzimática/efeitos dos fármacos , Feminino , Indometacina/farmacologia , Cinética , Inibidores de Lipoxigenase/farmacologia , Células Lúteas/efeitos dos fármacos , Masoprocol/farmacologia , Ácidos Fosfatídicos/metabolismo , Ratos , Ratos Sprague-Dawley , TrítioRESUMO
The human corpus luteum produces both estradiol and progesterone. It is well known that there are both autocrine and paracrine systems for the regulation of the corpus luteum and that estradiol regulates the progesterone production of the corpora lutea of some other species. To assess the direct effects of estrogen on human luteal function, we performed cell culture experiments. A low concentration of estradiol, almost equal to the amount of estradiol produced by human cultured luteal cells, directly stimulated progesterone production. 4-Cyclohexylaniline, an aromatase inhibitor, significantly reduced both progesterone production and estradiol production. Levels of estradiol higher than the levels that cultured human luteal cells themselves produced significantly reduced basal progesterone production and also significantly reduced human chorionic gonadotropin (hCG), forskolin and dibutyryl-cyclic AMP-stimulated progesterone production. According to these data, high doses of estradiol produced a luteolytic action which widely inhibited the steroidogenesis process. In conclusion, our results indicated that estradiol in part regulates progesterone production physiologically and blocks progesterone production in a pharmacological or pathological state in the human corpus luteum.
Assuntos
Compostos de Anilina/farmacologia , Inibidores da Aromatase , Corpo Lúteo/fisiologia , Estradiol/farmacologia , Células Lúteas/metabolismo , Progesterona/biossíntese , Bucladesina/farmacologia , Células Cultivadas , Gonadotropina Coriônica/farmacologia , Colforsina/farmacologia , AMP Cíclico/metabolismo , Estradiol/biossíntese , Estradiol/metabolismo , Feminino , Humanos , Células Lúteas/efeitos dos fármacos , RadioimunoensaioRESUMO
There are two stages of luteal regression. The first stage is functional regression that is characterized by a decreased production of progesterone secretion; the second stage of structural involution is referred to as a structural luteolysis. In rodents, prolactin has a biphasic action on the corpus luteum. It is luteotrophic, but when exposed to functionally regressed corpora lutea it causes luteolysis. The objective of the present studies was to examine mechanisms of prolactin action in structural luteolysis, whether apoptosis is involved in this process, and to examine the possible association of cell proliferation signals as mediators of structural luteolysis. Prolactin-induced structural luteolysis was associated with apoptosis verified by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL). Apoptotic cells made up about 3% of the cells 24 hours after the first injection of prolactin, a level that remained constant at all stages of structural luteolysis. Total ovarian weight and DNA content were decreased about 50% in 72 hours after induction of structural luteolysis by prolactin, The finding of about 3% of cells in apoptosis indicates apoptosis is a rapid process. Proliferating cell nuclear antigens (PCNA) of luteal cells were significantly decreased during functional luteal regression, but were conversely increased in structural luteolysis as shown by western blotting and immunohistochemistry. In general PCNA expression is reported to be decreased during structural involution, and there are no reports that have linked excess expression of PCNA with apoptosis and structural luteolysis. We speculate that an excessive increase in expression of PCNA which signals activation of cell proliferation creates a disorder in the signals involved with DNA synthesis. This disorder results in mitotic catastrophe and in the induction of apoptosis. Therefore the disorder of cell cycle signals in luteal cells are associated with prolactin induced apoptosis in structural luteolysis.
Assuntos
Apoptose/fisiologia , Corpo Lúteo/crescimento & desenvolvimento , Luteolíticos/farmacologia , Prolactina/farmacologia , Antígeno Nuclear de Célula em Proliferação/biossíntese , Animais , Western Blotting , Corpo Lúteo/efeitos dos fármacos , Corpo Lúteo/metabolismo , DNA/biossíntese , Feminino , Imuno-Histoquímica , Gravidez , Progestinas/metabolismo , Proteínas/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
In general, growth hormone acts as a factor promoting cell proliferation in the positive direction and suppresses apoptosis. No report has described growth hormone (GH)-induced structural luteolysis. The present studies showed that GH induced structural luteolysis in rats after the induction of functional luteolysis by treatment with bromocriptine, and that apoptotic cells were present among luteal cells during structural luteolysis as shown by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling. Zymography showed that the activity of matrix metalloproteinase (MMP)-2 increased during GH-induced structural luteolysis. The expression of c-myc protein of luteal cells was significantly decreased, but proliferating cell nuclear antigens (PCNA) were conversely increased during structural luteolysis, as shown by Western blot analysis. We propose that an excessive increase in PCNA and a marked decrease in c-myc protein of luteal cells lead to a disorder in the signals concerned with DNA synthesis, causing mitotic catastrophe and inducing apoptosis in luteal cells, and that structural luteolysis may be triggered. GH-induced apoptosis in structural luteolysis therefore highly depends on the cell cycle. There are thought to be two mechanisms of GH-induced structural luteolysis. One is apoptosis, and the other is destruction of extracellular matrix by MMP.
Assuntos
Corpo Lúteo/efeitos dos fármacos , Hormônio do Crescimento Humano/farmacologia , Superovulação , 20-alfa-Di-Hidroprogesterona/sangue , Animais , Apoptose/efeitos dos fármacos , Bromocriptina/farmacologia , Corpo Lúteo/citologia , Corpo Lúteo/metabolismo , Feminino , Gelatinases/metabolismo , Humanos , Luteólise/sangue , Luteólise/efeitos dos fármacos , Luteólise/metabolismo , Metaloproteinase 2 da Matriz , Metaloendopeptidases/metabolismo , Peso Molecular , Tamanho do Órgão/efeitos dos fármacos , Progesterona/sangue , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
Polycystic ovary syndrome (PCOS) is characterized by cystogenesis; however, the cause of this cystogenesis is unknown. At ovulation, preovulatory collagenolytic activities in the ovarian follicles increase and various proteinases are needed to degrade the tissues surrounding the follicles. To clarify the roles of enzymes in collagen degradation of the follicular wall of polycystic ovary (PCO) in relation to the cystogenesis, we examined expression of lysyl oxidase (LOX), which initiates cross-link formation of the collagen and elastin in the extracellular matrix, and expression of matrix metalloproteinases (MMPs) in ovaries of model rats with PCO induced by dehydroepiandrosterone (DHEA) compared with MMP expression in control rats. DHEA treatment increased LOX mRNA expression to more than three times the control value (P: < 0.01). MMP-2 mRNA expression in control rats was threefold greater than that in the DHEA-induced group (P: < 0.05). Expression of both latent and active forms of MMP-2 in controls was more than twice that in the DHEA-induced group (P: < 0.05) as shown by Western blotting, and expression of the active form of MMP-2 was also twice as high in the controls as in the DHEA-treated group (P: < 0.05) as shown by zymography. Our results suggest that depression of MMP-2 activity and increased LOX expression may be one of the causes of the cystogenesis of PCO.