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1.
J Anim Sci ; 87(10): 3235-43, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19542505

RESUMO

Ninety weanling pigs in Exp. 1 (6.27 +/- 0.73 kg; 21 d of age) and 96 growing pigs in Exp. 2 (21.73 kg +/- 1.29 kg; 56 d of age) were used in two 42-d experiments to evaluate the effect of phenyllactic acid (PLA) on growth performance, apparent total tract digestibility (ATTD) of DM and N, fecal pH value, microbial shedding, and blood profiles. In Exp. 1, the 3 dietary treatments were 1) negative control (NC), 2) positive control (PC), NC + antibiotics, and 3) PLA, NC + 0.5% PLA. In Exp. 2, dietary treatments were 1) control diet (CON), 2) PLA-0.1, CON + 0.1% PLA, 3) PLA-0.2, CON + 0.2% PLA, and 4) PLA-0.3, CON + 0.3% PLA. In Exp. 1, pigs fed the PC and PLA diets had greater ADFI during the overall period (P < 0.05) and tended to have greater ADG and G:F from d 7 to 21 (P < 0.10) than those fed the NC diet. The ATTD of DM was greatest in pigs fed the PLA diet on d 20 and 41, and N digestibility on d 20 was greater in pigs fed the PLA diet (P < 0.05) than those fed the NC diet. The numbers of white blood cell and lymphocyte concentrations on d 42 were increased (P < 0.05) by the inclusion of antibiotics and PLA in the diet. In Exp. 2, G:F tended to increase when PLA was added (quadratic, P < 0.10). The ATTD of DM did not differ among treatments, but there was a tendency (quadratic, P < 0.10) for N digestibility to increase as PLA levels increased. The lymphocyte percentage on d 42 increased linearly as dietary PLA increased (P < 0.05). Additionally, the white blood cell counts on d 42 tended to increase as PLA levels increased (P < 0.10). In both experiments, there was no effect of treatment on the fecal pH or presence of Lactobacillus, but the number of Escherichia coli in feces on d 41 decreased in response to the addition of PLA [P < 0.05 and 0.001 (linear) in Exp. 1 and 2, respectively]. In conclusion, PLA can decrease the number of E. coli, and this novel dietary acid may have potential to stimulate the immune system for both weanling and growing pigs. Thus, it could be a good candidate as an alternative to antibiotics in pig diets.


Assuntos
Digestão/fisiologia , Escherichia coli/isolamento & purificação , Ácido Láctico/análogos & derivados , Nitrogênio/metabolismo , Suínos/metabolismo , Animais , Contagem de Células Sanguíneas/veterinária , Proteínas Sanguíneas/análise , Contagem de Colônia Microbiana/veterinária , Fezes/química , Fezes/microbiologia , Feminino , Concentração de Íons de Hidrogênio , Imunoglobulina G/sangue , Ácido Láctico/farmacologia , Masculino , Distribuição Aleatória , Suínos/crescimento & desenvolvimento , Suínos/microbiologia
2.
Poult Sci ; 88(3): 593-600, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19211530

RESUMO

This study was conducted to evaluate the effects of dietary supplementation with chitooligosaccharide (COS) on growth performance, blood characteristics, relative organ weight, and meat quality in broilers. A total of 480 broilers with an average initial BW of 45.04 g per chick were randomly allocated into 1 of the following 4 dietary treatments (20 broilers per pen with 6 pens per treatment): 1) CON (basal diet), 2) ANT (basal diet + 44 mg/kg of avilamycin), 3) COS0.2 (basal diet + 14 g/kg of COS), 4) COS0.4 (basal diet + 28 g/kg of COS). The experiment lasted for 5 wk and avilamycin was administered from d 0 to 21. Growth performance was measured on d 0, 21, and 35, and all other response criteria were measured on d 35. No change in feed conversion (G:F) was observed in response to any of the treatments throughout the experimental period (P > 0.05). However, BW gain and feed intake were greater (P < 0.05) in broilers provided with feed supplemented with COS than in those in the control group. In addition, broilers had significantly greater (P < 0.05) red blood cell and high-density lipoprotein cholesterol concentrations when they were provided with the COS0.4 diet, whereas the triglyceride concentration was lower (P < 0.05) in broilers in the COS0.2 treatment group. No other blood characteristics were affected by the treatments. Additionally, as the dietary COS concentration increased, the liver weight increased (P < 0.05). Conversely, as the concentrations of dietary COS increased, abdominal fat decreased (P < 0.05). Furthermore, meat yellowness decreased (P < 0.05) as the concentration of COS increased. Finally, the breast meat and abdominal fat of birds provided with feed supplemented with COS had a lower (P < 0.05) saturated fatty acid concentration but a greater concentration of total monounsaturated fatty acids (P < 0.05) than that of birds in the control. In conclusion, COS can improve the performance and breast meat quality of broilers while increasing the red blood cell and high-density lipoprotein cholesterol concentrations in blood. In addition, COS can induce a decrease in abdominal fat and improve meat quality.


Assuntos
Suplementos Nutricionais , Carne/normas , Oligossacarídeos/farmacologia , Tecido Adiposo/anatomia & histologia , Tecido Adiposo/efeitos dos fármacos , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bolsa de Fabricius/anatomia & histologia , Bolsa de Fabricius/efeitos dos fármacos , Galinhas/sangue , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Moela das Aves/anatomia & histologia , Moela das Aves/efeitos dos fármacos , Fígado/anatomia & histologia , Fígado/efeitos dos fármacos , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/efeitos dos fármacos , Tamanho do Órgão , Baço/anatomia & histologia , Baço/efeitos dos fármacos
3.
Yonsei Med J ; 42(4): 367-70, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11519076

RESUMO

Soft-tissue lateral neck radiography is important for diagnosing acute supraglottitis. This study aimed to determine the objective criteria for a diagnosis of acute supraglottitis from soft-tissue lateral neck radiographs in Korean adults. The parameters in 30 adult patients with acute supraglottitis were compared with those of age- and sex-matched normal 30 Korean adults. The mean of epiglottis width (EW) and aryepiglottic fold width (AEW) in the control group were 4.37 +/- 0.93 mm, 2.45 +/- 0.71 mm, respectively and in the patient group they were 15.87 +/- 3.60 mm, 6.4 +/- 2.55 mm, respectively. The sensitivity and specificity of an EW greater than 7 mm were 100%, and 100% respectively. The sensitivity and specificity of an AEW greater than 4.5 mm were 83%, and 100% respectively.


Assuntos
Epiglotite/diagnóstico por imagem , Laringe/diagnóstico por imagem , Doença Aguda , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia
4.
J Oral Maxillofac Surg ; 58(8): 847-51, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10935582

RESUMO

PURPOSE: This article describes the endonasal endoscopic reduction (EER) of blowout fractures (BOFs) of the medial orbital walls and reports the clinical results. PATIENTS AND METHODS: Sixteen patients who underwent EER for a BOF of the medial orbital wall were analyzed. The surgical indications for treatment were diplopia, limitation of eye movements, and significant enophthalmos. They were followed-up for at least 3 months after the surgery. Surgical techniques, surgical results, and postoperative complications were reviewed. RESULTS: There were no significant intraoperative or postoperative complications. Fourteen patients showed complete resolution of symptoms after the surgery. One patient, who had persistent diplopia and remaining enophthalmos, underwent medial wall reconstruction with a Medpor surgical implant (Porex Surgical Inc, College Park, GA) by a transorbital approach. Another patient, who had residual enophthalmos, had correction of enophthalmos after insertion of a Medpor implant. Both patients are now symptom-free. CONCLUSION: The results indicate that EER is a safe and effective technique for the treatment of BOFs of the medial orbital wall.


Assuntos
Endoscopia/métodos , Nariz/cirurgia , Fraturas Orbitárias/cirurgia , Adolescente , Adulto , Diplopia/etiologia , Enoftalmia/etiologia , Feminino , Fixação Interna de Fraturas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos da Motilidade Ocular/etiologia , Fraturas Orbitárias/complicações , Avaliação de Processos e Resultados em Cuidados de Saúde , Estudos Retrospectivos
5.
J Oral Maxillofac Surg ; 58(6): 617-20; discussion 620-1, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10847282

RESUMO

PURPOSE: This study investigated the relationship between the extent of fracture and enophthalmos in blowout fractures of the medial orbital wall. PATIENTS AND METHODS: Nine patients with isolated blowout fractures of the medial orbital wall, confirmed by computed tomography scans, were evaluated. The area of fracture and the volume of herniated orbital tissue were determined from computed tomography scans using simple linear measurements. Each of the calculated values for area and volume were compared with the degree of enophthalmos to determine whether there was any significant relationship between them. RESULTS: Enophthalmos increased proportionally as the area of fracture or the volume of herniated orbital tissue increased (P < .05). The area of fracture and the volume of herniated orbital tissue associated with 2 mm of enophthalmos were 1.9 cm2 and 0.9 mL, respectively, as calculated from the regression curve. CONCLUSION: Enophthalmos of 2 mm or more, which is a frequent indication for surgery, can be expected when the area of fracture is 1.9 cm2 or more, or the volume of herniated orbital tissue is 0.9 mL or more.


Assuntos
Enoftalmia/etiologia , Enoftalmia/patologia , Fraturas Orbitárias/complicações , Fraturas Orbitárias/patologia , Adulto , Feminino , Humanos , Modelos Lineares , Masculino , Fatores de Risco , Índices de Gravidade do Trauma
6.
Exp Mol Med ; 32(4): 193-6, 2000 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-11190269

RESUMO

Centrosomes maintain genomic stability by establishing the bipolar spindles during cell division and, execute accurate segregation of chromosomes during mitosis. In this study, we have demonstrated that there are three forms of STK-15 gene in breast cancer cell lines. Alternative splice positions are located in 5'-untranslated region of STK15 gene. The results of in vitro translation experiments revealed that the alternative splicing in the 5'-untranslated region of STK15 had no effect on protein translation. The differential expression patterns of these alternatively spliced STK15 in breast cell lines and primary tumors therefore suggest that STK15 gene transcription may be differentially regulated or stabilized in these cells.


Assuntos
Regiões 5' não Traduzidas , Processamento Alternativo , Neoplasias da Mama/genética , Centrossomo/enzimologia , Proteínas Serina-Treonina Quinases/genética , Aurora Quinase A , Aurora Quinases , Sequência de Bases , Neoplasias da Mama/enzimologia , Feminino , Humanos , Dados de Sequência Molecular , Células Tumorais Cultivadas
7.
Auris Nasus Larynx ; 26(4): 441-5, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10530740

RESUMO

A lacrimal sac mucocele is an uncommon disease usually treated by ophthalmologists. In rare cases, it is sometimes associated with a nasolacrimal duct cyst presenting as an intranasal cystic mass, which needs the involvement of an otolaryngologist in diagnosis and management. Two cases of lacrimal sac mucoceles with nasolacrimal duct cysts are presented with a brief literature review. Both cases presented with intranasal cystic masses that caused nasal obstruction and were cured with endoscopic marsupialization of the cysts.


Assuntos
Endoscopia/métodos , Mucocele/complicações , Mucocele/patologia , Ducto Nasolacrimal/patologia , Adulto , Criança , Feminino , Humanos , Masculino , Seios Paranasais/diagnóstico por imagem , Tomografia Computadorizada por Raios X
8.
J Korean Med Sci ; 13(2): 223-6, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9610628

RESUMO

Subcutaneous cervical and mediastinal emphysema usually can occurs as a result of surgery or trauma. Spontaneous cervical subcutaneous emphysema and pneumomediastinum, occurring in the absence of previous disorders or provocating factors, is very rare. The following case report of spontaneous cervical and mediastinal emphysema is assumed to be the first of its kind in Korea. The patient has been followed up for three years without recurrence or sequelae.


Assuntos
Enfisema Mediastínico/diagnóstico por imagem , Enfisema Subcutâneo/diagnóstico por imagem , Adolescente , Feminino , Humanos , Enfisema Mediastínico/complicações , Cervicalgia , Enfisema Subcutâneo/complicações , Tomografia Computadorizada por Raios X
10.
Laryngoscope ; 107(2): 222-7, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9023247

RESUMO

The 68-kDa antigen detected in the sera of patients with autoimmune inner ear disease is known to represent the highly inducible heat shock protein 70 (hsp70). To evaluate the existence of anti-hsp70 in the sera of patients with Meniere's disease and to develop a more reliable method to detect this antibody, the sera of patients and controls were examined. Bovine kidney (MDBK) cells were cultured and some of them were heat shocked. Proteins in the cells were separated using sodium dodecyl sulfate polyacrylamide gel electrophoresis. Sera were reacted simultaneously with the blots of non-heat-shocked cells and heat-shocked cells. The serum was considered positive if the band in the 70-kDa location was denser in the lane with heat-shocked cells relative to non-heat-shocked cells. Presence of the antibody against the 68-kDa protein was compared with the result of immunoblotting with MDBK cells. In immunoblotting with MDBK cells, 33.3% of patients with Meniere's disease had anti-hsp70, while in the control group, only 5% had this antibody. Of the 60 cases, 13 were positive against both hsp70 and the 68-kDa protein, whereas 7 were positive only against hsp70 and 6 only against the 68-kDa protein. These differences appeared to result from the greater sensitivity of the differential anti-hsp assay and from difficulties in interpreting the results in blots with bovine inner ear extracts because of faint, broad, or overlapping multiple bands. Quite a number of patients with Meniere's disease have anti-hsp70, and it may be indicative of an immune etiology of the disease. The Western blot using heat-shocked and non-heat-shocked cells could be a reliable method to detect this antibody.


Assuntos
Orelha Interna/imunologia , Proteínas de Choque Térmico HSP70/imunologia , Doença de Meniere/imunologia , Adulto , Idoso , Animais , Anticorpos/sangue , Western Blotting , Bovinos , Linhagem Celular , Feminino , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Immunoblotting , Imunoeletroforese , Rim/imunologia , Masculino , Doença de Meniere/metabolismo , Pessoa de Meia-Idade
11.
Int J Biochem Cell Biol ; 28(8): 895-903, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8811837

RESUMO

In order to investigate microsomal diacylglycerol acyltransferase activity, ethanol or several detergents have been used as a dispersing agent for water-insoluble substrates. However, ethanol acyltransferase interferes with the activity of this enzyme, and detergents inhibit it. We examined the properties of microsomal diacylglycerol acyltransferase in rat salivary glands without detergents or organic solvents. 1,2-Dioleoyl-sn-glycerol (1,2-diolein) was dispersed by sonication. The activity was measured as the formation rate of [14C]triglyceride using [1-14C]palmitoyl-CoA as an acyl-donor. The reaction was dependent on the microsomal protein and 1,2-diolein at least up to 145 micrograms/ml and 3.6 mM, respectively. The specific activities were 3.91 +/- 0.57 and 3.80 +/- 0.77 nmol/min per mg protein (SEM, n = 4) in the parotid and submandibular glands, respectively. They were 12- to 20-fold higher than the activities in liver, brain and spleen, and two orders of magnitude higher than that assayed with microsomal endogenous diacylglycerol. Adding tissue phospholipids to 1,2-diolein suspension reduced the concentration of 1,2-diolein required for the maximal velocity. A similar, but reduced, effect was induced by egg yolk phosphatidylcholine in place of the tissue phospholipids. The level of activity was recovered by adding another phospholipid class to the phosphatidylcholine. The results suggested that the physical condition of the substrate diacylglycerol affects diacylglycerol acyltransferase activity in rat salivary gland microsomes.


Assuntos
Aciltransferases/metabolismo , Diglicerídeos/metabolismo , Microssomos/enzimologia , Glândula Parótida/enzimologia , Fosfolipídeos/metabolismo , Glândula Submandibular/enzimologia , Animais , Diacilglicerol O-Aciltransferase , Masculino , Glândula Parótida/ultraestrutura , Ratos , Ratos Wistar , Glândula Submandibular/ultraestrutura , Especificidade por Substrato
12.
Biochim Biophys Acta ; 1258(3): 288-96, 1995 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-7548199

RESUMO

Microsomal 1-acyl-sn-glycero-3-phosphoinositol (1-acyl-GPI) acyltransferase in the rat submandibular gland showed the highest specific activities for eicosanoid-related polyunsaturated acyl-CoAs, such as arachidonoyl-, bishomo-gamma-linolenoyl- and 5,8,11,14,17-eicosapentaenoyl-CoAs, with low Km values. High activities were also obtained with acyl-CoAs having long (more than 14 carbon atoms) and n - 6 unsaturated (more than 3 double bonds) acyl chains. This enzyme also utilized acyl-CoAs having trans-unsaturated or branched chains, but not short-chains, as substrates, although the activity levels for trans-unsaturated acyl-CoAs were lower than those for cis-unsaturated acyl-CoAs. Chronic administration of isoproterenol induced decreases of this enzyme activity and the content of arachidonic, bishomo-gamma-linolenic and 5,8,11,14,17-eicosapentaenoic acids at the sn-2 position of phosphatidylinositol. These results suggest that enrichment of arachidonic acid in the sn-2 position of phosphatidylinositol is established by the high specificity and affinity of 1-acyl-GPI acyltransferase for arachidonoyl-CoA. On the other hand, the low level of bishomo-gamma-linolenic and 5,8,11,14,17-eicosapentaenoic acids in the sn-2 position of phosphatidylinositol may be explained by their limited availability.


Assuntos
Acil Coenzima A/metabolismo , Aciltransferases/metabolismo , Ácidos Graxos Insaturados/metabolismo , Fosfatos de Inositol/metabolismo , Microssomos/enzimologia , Glândula Submandibular/enzimologia , Acil Coenzima A/química , Animais , Fracionamento Celular , Detergentes/farmacologia , Ácido Ditionitrobenzoico/metabolismo , Eicosanoides/química , Eicosanoides/metabolismo , Ácidos Graxos Insaturados/química , Isoproterenol/farmacologia , Cinética , Masculino , Fosfatidilinositóis/metabolismo , Ratos , Ratos Wistar , Especificidade por Substrato
13.
J Biochem ; 118(4): 693-9, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8576080

RESUMO

We investigated the significance of the plasma membrane lipid composition in exocytosis in an in vitro interaction system using an intact secretory granular fraction (SG) isolated from the rat parotid gland. When various liposomes (as a model of plasma membranes) were added to this assay system, rapid and transient amylase release from the SG was evoked and increased by Ca2+ in a concentration-dependent manner. The extent depended upon not only the amount of liposomes but also their lipid composition. The addition of 1,2-diacylglycerol and phosphatidic acid to egg yolk phosphatidylcholine-liposomes remarkably facilitated the release. On the other hand, that of various free fatty acids had different effects depending upon their molecular species. Furthermore, a fluorescence de-quenching study demonstrated that membrane fusion actually occurred in this interaction system, and appeared to correlate with the amylase release. These results suggest that the transient alteration of the membrane lipid composition upon cell activation is a modulator of the exocytotic membrane interaction.


Assuntos
Amilases/metabolismo , Grânulos Citoplasmáticos/enzimologia , Exocitose , Lipídeos de Membrana/fisiologia , Glândula Parótida/fisiologia , Animais , Lipossomos , Masculino , Fusão de Membrana , Ratos , Ratos Wistar
14.
J Biochem ; 115(6): 1040-6, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7982879

RESUMO

Chronic (5- and 10-day) administration of isoproterenol, an agent that induces the proliferation of salivary gland cells, produced increases in microsomal 1-acyl-sn-glycero-3-phosphate acyltransferase and 1-acyl-sn-glycero-3-phosphocholine acyltransferase activity in rat parotid glands in parallel with gland enlargement. This increased activity was reduced when the treatment was stopped, the reduction corresponding to the reduction in gland weight. There were significant correlations between lysophospholipid acyltransferase activity and gland weight, and between the activities of the two types of lysophospholipid acyltransferase. However, isoproterenol treatment did not affect any of the steps of the subsequent phospholipid N-methylation. These results suggest that the cell proliferation induced by chronic administration of isoproterenol in the parotid gland is accompanied by reversible and selective increases in microsomal lysophospholipid acyltransferases.


Assuntos
1-Acilglicerofosfocolina O-Aciltransferase/efeitos dos fármacos , Isoproterenol/farmacologia , Microssomos/enzimologia , Doenças Parotídeas/enzimologia , 1-Acilglicerofosfocolina O-Aciltransferase/metabolismo , Animais , Divisão Celular/efeitos dos fármacos , Masculino , Metilação , Tamanho do Órgão/efeitos dos fármacos , Doenças Parotídeas/induzido quimicamente , Fosfolipídeos/metabolismo , Ratos , Ratos Sprague-Dawley , Glândula Sublingual/efeitos dos fármacos , Fatores de Tempo
15.
Otolaryngol Head Neck Surg ; 110(4): 419-27, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8170687

RESUMO

Guinea pigs were irradiated with fast neutrons. After a single dose of 2, 6, 10, or 15 Gy was applied, scanning and transmission electron microscopy of the temporal bone was performed to assess the effect of fast neutron irradiation on the cochlea. Outer hair cell damage appeared with neutron irradiation of more than 10 Gy, and inner hair cell damage with neutron irradiation of more than 15 Gy. Outer hair cells were more severely damaged than inner hair cells. No statistically significant differences were found in damage of basal, middle, and apical turns. The second and third rows of outer hair cells were more severely damaged than the first row of outer hair cells. The most significant findings in transmission electron microscopy were clumping of chromatin and extension of the heterochromatin in the nuclei of hair cells. The cytoplasmic changes were sequestration of cytoplasm, various changes of mitochondria, formation of vacuoles, and irregularly arranged stereocilia. The morphologic change in stria vascularis was intercellular and perivascular fluid accumulation. It appeared to be a reversible process.


Assuntos
Cóclea/efeitos da radiação , Cóclea/ultraestrutura , Nêutrons Rápidos , Neoplasias de Cabeça e Pescoço/radioterapia , Radioterapia de Alta Energia/efeitos adversos , Animais , Modelos Animais de Doenças , Estudos de Avaliação como Assunto , Cobaias , Microscopia Eletrônica de Varredura , Tolerância a Radiação , Dosagem Radioterapêutica , Radioterapia de Alta Energia/métodos
16.
Int J Biochem ; 26(2): 279-85, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7909756

RESUMO

1. Long-chain fatty acyl-CoA hydrolase in submandibular gland microsomes was characterized and compared to that in liver ones. 2. In rat submandibular gland, the microsomal long-chain acyl-CoA hydrolase showed a higher relative activity for polyunsaturated fatty acyl-CoAs than that of liver microsomes. 3. It was suggested that the hydrolase in rat submandibular gland microsomes may play a role in modulation in the acyl-CoA pool size.


Assuntos
Microssomos/enzimologia , Palmitoil-CoA Hidrolase/análise , Glândula Submandibular/enzimologia , Animais , Masculino , Lipídeos de Membrana/química , Microssomos Hepáticos/enzimologia , Especificidade de Órgãos/fisiologia , Fosfolipídeos/química , Ratos , Ratos Wistar , Glândula Submandibular/ultraestrutura , Especificidade por Substrato
17.
Biochim Biophys Acta ; 1116(2): 104-11, 1992 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-1374645

RESUMO

A secretory granular fraction (SG) and a plasma membrane rich fraction (PM) have been isolated from rat parotid gland by differential and Percoll gradient centrifugation. With these two fractions, a cell-free interaction system has been reconstituted to clarify the exocytotic interaction between the secretory granules and plasma membranes, and the conditions of amylase release from SG have been characterized in vitro. The addition of PM into this assay system induced a rapid and transient release of amylase from SG. Some other membranes such as erythrocyte ghosts also mimicked the effect of PM. This release was increased by Ca2+, but was not completely blocked by EGTA. Simultaneous addition of 1 mM ATP with 1 mM MgCl2 (Mg-ATP) in the presence of Ca2+ reduced this release. However, in spite of the existence of Mg-ATP, the stimulation of PM-induced amylase release was caused by Ca2+ in a concentration-dependent manner (10(-7)-10(-3) M). These results suggest that Ca2+ and Mg-ATP should participate as important regulators in the exocytotic interaction between secretory granules and plasma membranes in this system. Furthermore, the differences between our system and intact cells are also discussed.


Assuntos
Trifosfato de Adenosina/farmacologia , Amilases/metabolismo , Cálcio/farmacologia , Membrana Celular/fisiologia , Grânulos Citoplasmáticos/enzimologia , Membrana Eritrocítica/fisiologia , Glândula Parótida/enzimologia , Animais , Fracionamento Celular/métodos , Membrana Celular/ultraestrutura , Centrifugação com Gradiente de Concentração/métodos , Grânulos Citoplasmáticos/efeitos dos fármacos , Grânulos Citoplasmáticos/ultraestrutura , Ácido Egtázico/farmacologia , Humanos , Cinética , Lipossomos , Masculino , Fosfatidilcolinas , Ratos , Ratos Endogâmicos , Ultracentrifugação/métodos
18.
Gifu Shika Gakkai Zasshi ; 17(2): 547-56, 1990 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-2133668

RESUMO

The major constituent free fatty acid in rat parotid and submandibular glands was palmitic acid (about 40% of the total), followed by saturated and unsaturated fatty acids with 18 carbon atoms and arachidonic acid. The composition was changed by chronic administration of isoproterenol, with an increase of linoleic acid and a decrease of arachidonic acid coinciding with changes in the acyl composition of phospholipids. With respect to the metabolism of unsaturated fatty acids, delta 6-desaturation activity converting linoleic acid to gamma-linolenic acid was detected using [14C]linoleoyl-CoA in the submandibular gland. These results suggest that changes in the acyl composition of phospholipids induced by chronic administration of isoproterenol are in part due to changes in free fatty acid composition and that delta 6-desaturation activity may be involved in the regulation of unsaturated fatty acid composition.


Assuntos
Ácidos Graxos não Esterificados/metabolismo , Isoproterenol/farmacologia , Glândulas Salivares/química , Animais , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos Insaturados/metabolismo , Ácido Linoleico , Ácidos Linoleicos/metabolismo , Fosfolipídeos/química , Ratos , Glândulas Salivares/efeitos dos fármacos
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