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1.
Cell Calcium ; 29(1): 49-58, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11133355

ABSTRACT

Two potential mechanisms by which the intracellular Ca(2 stores might modulate catecholamine release from bovine adrenal chromaffin cells were investigated: (i) that the cytosolic Ca(2+)transient caused by Ca(2+)release from the intracellular stores recruits additional chromaffin granules to a readily releasable pool that results in augmented catecholamine release when this is subsequently evoked, and (ii) that the Ca(2+)influx that follows depletion of intracellular stores (i.e. store-operated Ca(2+)entry) triggers release per se thereby augmenting evoked catecholamine release. When histamine or caffeine were applied in Ca(2+)-free perfusion media, a transient elevation of intracellular free Ca(2+)occurred owing to mobilization of Ca(2+)from the stores. When Ca(2+)was later readmitted to the perfusing fluid there followed a prompt and maintained rise in intracellular Ca(2+)concentrations of magnitude related to the degree of store mobilization. In parallel experiments, increased catecholamine secretion was measured under the conditions when Ca(2+)influx following store-mobilization occurred. Furthermore, the size of the catecholamine release increment correlated with the degree of Ca(2+)influx. Store-operated Ca(2+)entry evoked by mobilization with histamine and/or caffeine did not augment nicotine-evoked secretion per se; that is, it augmented evoked catecholamine release only to the extent that it increased basal catecholamine release. The nicotine-evoked catecholamine release was sensitive to cytosolic BAPTA, which, at the concentration used (50 microM BAPTA-AM), reduced release by approximately 25%. However, the increment in basal catecholamine release which followed Ca(2+)influx triggered by Ca(2+)store mobilization was not reduced by intracellular BAPTA. This finding is inconsistent with the hypothesis that the elevated cytosolic Ca(2+)from store mobilization recruits additional vesicles of catecholamine to the sub-plasmalemmal release sites to augment subsequently evoked secretion. This position is supported by the observation that histamine (10 microM) in Ca(2+)-free medium caused a pronounced elevation of cytosolic free Ca(2+), but this caused no greater catecholamine release when Ca(2+)was re-introduced than did prior exposure to Ca(2+)-free medium alone, which caused no elevation of cytosolic free Ca(2+). It is concluded that intracellular Ca(2+)stores can modulate secretion of catecholamines from bovine chromaffin cells by permitting Ca(2+)influx through a store-operated entry pathway. The results do not support the notion that the Ca(2+)released from intracellular stores plays a significant role in the recruitment of vesicles into the ready-release pool under the experimental conditions reported here.


Subject(s)
Calcium/metabolism , Chromaffin Cells/metabolism , Epinephrine/metabolism , Norepinephrine/metabolism , Adrenal Medulla/cytology , Animals , Caffeine/pharmacology , Calcium/pharmacology , Cattle , Cells, Cultured , Chelating Agents/pharmacology , Chromaffin Cells/cytology , Cytosol/metabolism , Egtazic Acid/analogs & derivatives , Egtazic Acid/pharmacology , Exocytosis/drug effects , Exocytosis/physiology , Fluorescent Dyes , Fura-2 , Histamine/pharmacology , Phosphodiesterase Inhibitors/pharmacology , Receptors, Nicotinic/metabolism
2.
J Neurochem ; 75(3): 1162-71, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10936199

ABSTRACT

The effect on exocytosis of La(3+), a known inhibitor of plasma membrane Ca(2+)-ATPases and Na(+)/Ca(2+) exchangers, was studied using cultured bovine adrenal chromaffin cells. At high concentrations (0.3-3 mM), La(3+) substantially increased histamine-induced catecholamine secretion. This action was mimicked by other lanthanide ions (Nd(3+), Eu(3+), Gd(3+), and Tb(3+)), but not several divalent cations. In the presence of La(3+), the secretory response to histamine became independent of extracellular Ca(2+). La(3+) enhanced secretion evoked by other agents that mobilize intracellular Ca(2+) stores (angiotensin II, bradykinin, caffeine, and thapsigargin), but not that due to passive depolarization with 20 mM K(+). La(3+) still enhanced histamine-induced secretion in the presence of the nonselective inhibitors of Ca(2+)-permeant channels SKF96365 and Cd(2+), but the enhancement was abolished by prior depletion of intracellular Ca(2+) stores with thapsigargin. La(3+) inhibited (45)Ca(2+) efflux from preloaded chromaffin cells in the presence or absence of Na(+). It also enhanced and prolonged the rise in cytosolic [Ca(2+)] measured with fura-2 during mobilization of intracellular Ca(2+) stores with histamine in Ca(2+)-free buffer. The results suggest that the efficacy of intracellular Ca(2+) stores in evoking exocytosis is enhanced dramatically by inhibiting Ca(2+) efflux from the cell.


Subject(s)
Adrenal Medulla/physiology , Calcium/metabolism , Chromaffin Cells/physiology , Exocytosis/physiology , Lanthanum/pharmacology , Metals, Rare Earth/pharmacology , Norepinephrine/metabolism , Adrenal Medulla/cytology , Angiotensin II/pharmacology , Animals , Cadmium/pharmacology , Caffeine/pharmacology , Calcium Channel Blockers/pharmacology , Cattle , Cells, Cultured , Chromaffin Cells/cytology , Chromaffin Cells/drug effects , Exocytosis/drug effects , Histamine/pharmacology , Imidazoles/pharmacology , Kinetics
3.
Br J Pharmacol ; 128(7): 1435-44, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10602322

ABSTRACT

1. The effects of Gd3+ on bradykinin- (BK-) induced catecholamine secretion, 45Ca2+ efflux and cytosolic [Ca2+] were studied using bovine adrenal chromaffin cells. 2. BK increased secretion in a Ca2+-dependent manner. From 1 - 100 microM, Gd3+ progressively inhibited secretion induced by 30 nM BK to near-basal levels, however from 0.3 - 3 mM Gd3+ dramatically enhanced BK-induced secretion to above control levels. Gd3+ also increased basal catecholamine secretion by 2 - 3 fold at 1 mM. These effects were mimicked by Eu3+ and La3+. 3. Gd3+ enhanced secretion induced by other agonists that mobilize intracellular Ca2+ stores, but simply blocked the response to K+. 4. Gd3+ still enhanced basal and BK-induced secretion in Ca2+-free solution or in the presence of 30 microM SKF96365, however both effects of Gd3+ were abolished after depleting intracellular Ca2+ stores. 5. Gd3+ (1 mM) reduced the rate of basal 45Ca2+ efflux by 57%. In Ca2+-free buffer, BK transiently increased cytosolic [Ca2+] measured with Fura-2. The [Ca2+] response to BK was substantially prolonged in the presence of Gd3+ (1 mM). 6. The results suggest that Gd3+ greatly enhances the efficacy of Ca2+ released from intracellular stores in evoking catecholamine secretion, by inhibiting Ca2+ extrusion from the cytosol. This suggests that intracellular Ca2+ stores are fully competent to support secretion in chromaffin cells to levels comparable to those evoked by extracellular Ca2+ entry. Drugs that modify Ca2+ extrusion from the cell, such as lanthanide ions, will be useful in investigating the mechanisms by which intracellular Ca2+-store mobilization couples to Ca2+-dependent exocytosis.


Subject(s)
Bradykinin/pharmacology , Chromaffin Cells/drug effects , Chromaffin Cells/metabolism , Gadolinium/pharmacology , Norepinephrine/metabolism , Animals , Calcium/metabolism , Calcium/physiology , Calcium Channel Blockers/pharmacology , Calcium Radioisotopes , Cations, Divalent , Cattle , Epinephrine/metabolism , Extracellular Space/metabolism , Extracellular Space/physiology , Fluorescent Dyes , Fura-2 , Intracellular Fluid/metabolism , Secretory Rate/drug effects
4.
J Med Microbiol ; 47(7): 577-84, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9839561

ABSTRACT

Forty-six patients presenting with chronic orofacial muscle pain and eight age- and sex-matched control subjects were investigated for the carriage prevalence of, and exotoxin production by, coagulase-negative staphylococci (CNS). The eight control subjects were selected from an initial group of 41 subjects on the basis of the absence of musculoskeletal symptoms. There was a significantly higher prevalence and multiple carriage of four or more strains of CNS in patients with chronic muscle pain than in control subjects (23 versus 9 isolates/10 subjects). Two of the 103 CNS isolates from patients with muscle pain and none from the control subjects produced toxic shock syndrome toxin 1 (TSST-1), suggesting that pyrogenic toxins do not significantly contribute to the aetiology of chronic muscle pain. There was a significantly higher prevalence of delta-haemolysin (41 of 114) and 'horse'-haemolysin (56 of 114) production by CNS isolates from patients with chronic muscle pain compared with those from control subjects. None of the control subjects was colonised with CNS that produced significant amount of either delta- or 'horse'-haemolysin, whereas 35 of 44 patients with chronic orofacial muscle pain were colonised with CNS that produced significant amounts of 'horse'-haemolysin, 37 that produced delta-haemolysin and 33 that produced both delta- and horse-haemolysin. This study suggests that membrane-damaging toxins, like delta- and 'horse'-haemolysin, may play a role in the aetiology of chronic orofacial muscle pain.


Subject(s)
Bacterial Toxins/biosynthesis , Carrier State/epidemiology , Facial Pain/microbiology , Staphylococcal Infections/epidemiology , Staphylococcus/metabolism , Superantigens , Adolescent , Adult , Bacterial Proteins/biosynthesis , Carrier State/microbiology , Chronic Disease , Coagulase , Enterotoxins/biosynthesis , Female , Hemolysin Proteins/biosynthesis , Humans , Male , Middle Aged , Prevalence , Staphylococcal Infections/microbiology , Staphylococcus/enzymology , Staphylococcus/isolation & purification
5.
Alpha Omegan ; 91(2): 25-8, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9927897

ABSTRACT

The initial data from this study indicate that there are clearly identifiable chronic muscle pain conditions in the form of localized pain; myofascial pain or regional pain conditions; and fibromyalgia or generalized pain conditions. A clear difference exists between the prevalence of these conditions in male and female patients, with a higher percentage of female patients suffering generalized pain problems and temporomandibular problems. Generalized or localized pain appears to be an individual variant of a similar problem and pain patients may have a genetically determined vulnerability associated with bacterial toxins, particularly within the genitourinary tract. It appears that in fibromyalgia there is an underlying genetic factor that causes abnormalities in the muscle metabolic cycle, and preliminary data suggest that lipid anomalies predispose to fibromyalgia and possibly chronic fatigue syndrome. Patients report infectious events at/or around onset in more than 60 percent of cases. Seventy percent of fibromyalgic cases report orofacial pain.


Subject(s)
Facial Pain , Temporomandibular Joint Dysfunction Syndrome/diagnosis , Temporomandibular Joint Dysfunction Syndrome/therapy , Chronic Disease , Facial Pain/etiology , Female , Fibromyalgia/complications , Humans , Male , Masticatory Muscles/physiopathology , Temporomandibular Joint Dysfunction Syndrome/etiology
6.
Cell Calcium ; 23(6): 379-86, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9924629

ABSTRACT

The characteristics and properties of the increase in cytosolic [Ca2+] that occurs in bovine adrenal medullary chromaffin cells on exposure to histamine have been investigated. Specifically, these experiments were conducted to determine how much external Ca2+ enters the cell through a (capacitative) Ca2+ entry pathway activated as a consequence of intracellular Ca2+ store mobilization, relative to that which enters independently of store depletion via other channels activated by histamine. In Fura-2 loaded cells continued exposure to histamine (10 microM) caused a rapid but transient increase in cytosolic [Ca2+] followed by a lower plateau that was sustained as long as external Ca2+ was present. In the absence of external Ca2+, only the initial brief transient was observed. In cells previously treated with thapsigargin (100 nM) in Ca(2+)-free medium to deplete the internal Ca2+ stores, histamine caused no increase in cytosolic [Ca2+] when external Ca2+ was absent. Re-introduction of external Ca2+ to thapsigargin-treated store-depleted cells caused a sustained increase in cytosolic [Ca2+] that was further increased (P < 0.0002) upon exposure to histamine. The histamine-evoked increase was prevented by the H1-receptor antagonist, mepyramine (2 microM). A comparison was made between store-dependent Ca2+ entry consequent upon store mobilization with histamine in Ca(2+)-free medium and plateau phase Ca2+ entry resulting from stimulation with histamine in Ca(2+)-containing medium. The latter was found to be approximately 3 times greater in magnitude than the former (P << 0.0001) at the same concentration of histamine (10 microM). It is concluded that histamine causes Ca2+ entry not only via a capacitative entry pathway secondary to internal store mobilization, but also causes substantial Ca2+ entry through other pathways.


Subject(s)
Adrenal Glands/metabolism , Calcium/metabolism , Chromaffin Cells/metabolism , Histamine/pharmacology , Animals , Caffeine/pharmacology , Calcium/pharmacology , Cattle , Cells, Cultured , HEPES/pharmacology , Ion Transport/physiology , Lanthanum/pharmacology , Thapsigargin/pharmacology , Time Factors
7.
Biochem Mol Med ; 58(1): 85-92, 1996 Jun.
Article in English | MEDLINE | ID: mdl-8809350

ABSTRACT

Chronic fatigue syndrome (CFS) patients have a urinary metabolite labeled CFSUM1 with increased incidence (P < 0.004) and relative abundance (P < 0.00003). The relative abundances of urinary CFSUM1 and beta-alanine were associated with alterations in metabolite excretion and symptom incidence. In 20 CFS patients and 45 non-CFS subjects, symptom/metabolite associations were investigated by assessing symptom sensitivity and specificity, and symptom indices of total symptom incidence, CFS core symptoms, cognitive, neurological, musculoskeletal, gastrointestinal, infection-related and genitourinary symptom indices, as well as a visual analogue pain scale of average pain intensity. Thirty-three symptoms had significant (P < 0.005) sensitivity and specificity in the CFS patients compared to that in the non-CFS controls. Severe fatigue was the only symptom with 100% sensitivity and specificity and CFSUM1 excretion was the primary metabolite for expression of this symptom. All nine symptom indices had elevated responses in the CFS patients (all P < 0.0000001). Multiple regression analyses indicated that all the symptom indices had significant correlations (R) with changes in the urinary excretion of metabolites (P < 0.0001). CFSUM1 and beta-alanine were the first and second metabolites correlated with the CFS core symptom index and CFSUM1 was primarily associated with infection-related and musculoskeletal indices whereas beta-alanine was primarily associated with gastrointestinal and genitourinary indices. The strong associations of CFSUM1 and beta-alanine with CFS symptom expression provide a molecular basis for developing an objective test for CFS.


Subject(s)
Fatigue Syndrome, Chronic/urine , Pyrrolidines/urine , Adolescent , Adult , Female , Gas Chromatography-Mass Spectrometry , Humans , Male , Middle Aged , Regression Analysis , Sensitivity and Specificity
8.
Biochem Mol Med ; 57(2): 73-80, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8733884

ABSTRACT

Chronic fatigue syndrome (CFS/ME) is a debilitating fatigue illness that has an unknown etiology. We studied 20 chronic fatigue syndrome (CFS) patients, who complied with the Oxford and American CDC definitions, and 45 non-CFS subjects. Participants completed questionnaires, were clinically examined, and had first morning urine specimens collected, which were screened by gas chromatography-mass spectrometry for changes in metabolite excretion. Multivariate analysis of the urinary metabolite profiles differed significantly in the CFS patients compared to the non-CFS patients (P < 0.004). The CFS patients had increases in aminohydroxy-N-methylpyrrolidine (P < 0.00003, referred to as chronic fatigue symptom urinary marker 1, or CFSUM1), tyrosine (P < 0.02), beta-alanine (P < 0.02), aconitic acid (P < 0.05), and succinic acid (P < 0.05) and reductions in an unidentified urinary metabolite, CFSUM2 (P < 0.0007), alanine (P < 0.005), and glutamic acid (P < 0.02). CFSUM1, beta-alanine, and CFSUM2 were found by discriminant function analysis to be the first, second, and third most important metabolites, respectively for discriminating between CFS and non-CFS subjects. The abundances of CFSUM1 and beta-alanine were positively correlated with symptom incidence (P < 0.01 and P < 0.001, respectively), symptom severity, core CFS symptoms, and SCL-90-R somatization (P < 0.00001), suggesting a molecular basis for CFS.


Subject(s)
Fatigue Syndrome, Chronic/urine , Aconitic Acid/urine , Adolescent , Adult , Alanine/urine , Amino Acids/urine , Analysis of Variance , Biomarkers/urine , Fatigue Syndrome, Chronic/physiopathology , Fatigue Syndrome, Chronic/psychology , Female , Gas Chromatography-Mass Spectrometry , Glutamic Acid/urine , Humans , Male , Middle Aged , Multivariate Analysis , Physical Examination , Pyrrolidines/urine , Reference Values , Succinates/urine , Succinic Acid , Surveys and Questionnaires , Tyrosine/urine , beta-Alanine/urine
9.
J Orofac Pain ; 10(4): 339-50, 1996.
Article in English | MEDLINE | ID: mdl-9161239

ABSTRACT

A visual analog pain scale and scalar responses to 13 pain/symptom indicator Symptom Checklist-90-Revised (SCL-90-R) questions were used to assess symptom prevalence and pain severity in 43 chronic orofacial muscle pain patients and 40 control subjects. The orofacial muscle pain group reported pain in an axial skeletal distribution; neurocognitive, gastrogenitourinary, and musculoskeletal symptoms; infectious events at or preceding onset; similar symptoms in sexual partners; and low prevalence of trauma. Sudden onset was reported by 30.2% of pain patients. Strong associations were found between chronic orofacial muscle pain and (1) onset-related infectious-like events (67.4%); (2) a higher prevalence of history of respiratory and gastrogenitourinary infectious events; and (3) high prevalences of similar pain symptoms in long-term sexual partners. The SCL-90-R somatization scores (> 62) had a higher prevalence in the chronic pain group. No prevalence differences or associations with pain/symptom indicators were found for depression or anxiety dimension scores. These data suggest that patients with recurrent systemic infectious events have a higher prevalence of reporting of chronic orofacial muscle pain compared with control subjects, and these infectious events are associated with the onset of chronic orofacial muscle pain in 67% of patients.


Subject(s)
Facial Pain/etiology , Infections/complications , Temporomandibular Joint Dysfunction Syndrome/etiology , Adolescent , Adult , Aged , Case-Control Studies , Chi-Square Distribution , Chronic Disease , Cluster Analysis , Discriminant Analysis , Female , Humans , Logistic Models , Male , Middle Aged , Pain Measurement , Precipitating Factors , Sensitivity and Specificity , Severity of Illness Index , Statistics, Nonparametric , Surveys and Questionnaires
10.
Vet Microbiol ; 46(1-3): 213-9, 1995 Sep.
Article in English | MEDLINE | ID: mdl-8545959

ABSTRACT

Field samples were received for Marek's disease virus (MDV) isolation from clinically affected flocks from several regions of Eastern Australia. Lymphocytes were fractionated in Ficoll-Paque and passaged once or twice in chicken embryo kidney cultures. Serotype-specific virus was detected in infected cultures by indirect immunofluorescence with monoclonal antibodies. Serotype 1 MDV was isolated from 10 flocks. In samples from 5 of these flocks, serotype 2 and 3 vaccine viruses were isolated from the same specimen. In a parallel study, plasmas obtained during lymphocyte isolation were tested for antibodies to MDVs by agar gel precipitin (AGP) tests using serotype 1 and 3 antigen extracts. No correlation was observed between the rate of virus isolation and AGP positivity. The AGP test was incapable of discriminating between the different MDV serotypes.


Subject(s)
Herpesvirus 2, Gallid/classification , Lymphocytes/immunology , Lymphocytes/virology , Marek Disease/immunology , Vaccination , Animals , Australia , Cells, Cultured , Chick Embryo , Chickens , Fluorescent Antibody Technique, Indirect , Herpesvirus 2, Gallid/isolation & purification , Kidney , Marek Disease/prevention & control , Poultry , Precipitin Tests , Serotyping , Viral Vaccines
13.
Arch Virol ; 111(3-4): 227-38, 1990.
Article in English | MEDLINE | ID: mdl-2162161

ABSTRACT

A model for determining immunogenic relationships between strains of infectious bronchitis virus is described that is based upon the vaccinating dose required to induce prevention of multiplication of a standard challenge dose of an homologous strain in the lungs of specific-pathogen-free chickens. The model has been used to demonstrate that: (1) Approximately 100 times the vaccinating dose must be used to produce immunity from one compared with two doses; (2) differences of immunogenicity of greater than 1,000-fold exist between Australian strains; (3) immunogenicity is greatest for live virus administered directly to the trachea, followed by live virus administered by the ocular route, inactivated virus administered intratracheally and inactivated virus administered intramuscularly; (4) for chickens inoculated with Australian vaccine strains, protection against challenge is unrelated to serotype.


Subject(s)
Coronaviridae/immunology , Infectious bronchitis virus/immunology , Aging , Animals , Chick Embryo , Cross Reactions , Infectious bronchitis virus/classification , Infectious bronchitis virus/drug effects , Lung/microbiology , Models, Biological , Species Specificity , Specific Pathogen-Free Organisms , Viral Vaccines/administration & dosage , Viral Vaccines/immunology
14.
Zentralbl Chir ; 112(3): 188-91, 1987.
Article in German | MEDLINE | ID: mdl-2951942

ABSTRACT

Reported in this paper is experience obtained from coronary diagnosis and coronary fibrinolysis in acute myocardial infarction. Local fibrinolysis was applied to 69 patients, with 2 X 75,000 units of streptokinase in 30 minutes being the dose for orientation. Percutaneous transluminal coronary angioplasty was added in those cases in which therapeutic fibrinolysis proved to be insufficient. An additional bypass operation was required by nine patients.


Subject(s)
Angioplasty, Balloon , Combined Modality Therapy , Humans , Myocardial Infarction/therapy , Streptokinase/therapeutic use
15.
Biomed Biochim Acta ; 43(8-9): S447-50, 1984.
Article in English | MEDLINE | ID: mdl-6517907

ABSTRACT

We examined the fatty acid patterns of serum phospholipids, cholesterolesters, triglycerides and serum testosterone, estradiol, total cholesterol, triglycerides and HDL-cholesterol levels in the acute phase and after one, 6 and 12 months in a group of 27 male patients with myocardial infarction. These results were compared with the corresponding values of 19 healthy controls. Significant differences were discussed as the consequence of disturbed metabolism in patients with ischaemic heart diseases.


Subject(s)
Cholesterol Esters/blood , Fatty Acids/blood , Myocardial Infarction/blood , Phospholipids/blood , Triglycerides/blood , Follow-Up Studies , Humans , Reference Values
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