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1.
Artículo en Inglés | MEDLINE | ID: mdl-37943007

RESUMEN

OBJECTIVE: To study the safety and effectiveness of consecutively administered ropinirole and apomorphine (both dopamine 2-like receptor agonists) for emesis induction in dogs. DESIGN: Prospective, crossover study design. SETTING: Institutional animal research facility. ANIMALS: Six healthy male purpose-bred Beagle dogs. INTERVENTIONS: Each dog received 4 treatments: (1) apomorphine infusion (21 µg/kg) over 30 minutes + ropinirole eye drops (3.75 mg/m2 ); (2) ropinirole infusion (108 µg/m2 ) over 30 minutes + apomorphine SC (100 µg/kg); (3) apomorphine SC (100 µg/kg) + ropinirole eye drops (7.5 mg/m2 ) after 30 minutes; and (4) ropinirole eye drops (7.5 mg/m2 ) + apomorphine SC (100 µg/kg) after 30 minutes. Infusions were administered via a catheter instrumented in the cephalic vein. Eye drops and SC injections were administered as described in the product inserts. Blood samples were taken for ropinirole and apomorphine concentration analysis before dosing and periodically following administrations. The washout period between the treatments was 5-7 days. MEASUREMENTS AND MAIN RESULTS: Number of vomits and clinical signs were recorded. Alertness and heart rate were monitored in conjunction with blood sampling. The average number of vomits varied between 4.3 and 8.8 (range 1-16) following treatments. Signs of nausea, vomiting, and lethargy were seen in all individuals without significant differences between treatments. Moderate to marked, transient increase in heart rates was detected in all treatments. Infrequent noted side effects included ocular hyperemia, blepharospasms, and muscle tremors. Prior treatment with apomorphine significantly decreased the absorption of ropinirole eye drops. CONCLUSIONS: The safety and efficacy profiles of this experimental study support that ropinirole and apomorphine could be administered consecutively in cases where the treatment using 1 substance has resulted in an incomplete evacuation of the stomach contents, and the attending veterinarian considers the use of a different agent to have benefits that outweigh the risks.


Asunto(s)
Apomorfina , Indoles , Vómitos , Perros , Masculino , Animales , Estudios Cruzados , Estudios Prospectivos , Vómitos/inducido químicamente , Vómitos/tratamiento farmacológico , Vómitos/veterinaria , Soluciones Oftálmicas
2.
Front Immunol ; 13: 858875, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35693790

RESUMEN

Aims: Altered immune functions as well as fatty acid intake and status have been associated with the development of type 1 diabetes. We aimed to study the relationship between fatty acids and immunological markers in young children with increased genetic risk for type 1 diabetes in order to define putative mechanisms related to development of islet autoimmunity. Methods: Serum samples for fatty acid and immunological marker measurements were obtained in the Trial to Reduce IDDM in the Genetically at Risk (TRIGR) ancillary study (Divia) from children born between 2002 and 2007 in 15 countries. Case children (n = 95) were defined as having repeated positivity for at least two out of four diabetes-associated autoantibodies. For each case child, control children were selected matched for country and date of birth (n = 173). Serum fatty acids and immunological markers were measured from cord serum and at the age of 6 and 12 months. Spearman correlation coefficients were calculated between fatty acids and immunological markers. Results: Correlations between circulating fatty acids and immunological markers were different in case children who developed islet autoimmunity than in control children already at birth continuing across the first year of life. In case children, saturated fatty acids (SFAs) showed stronger correlations with immunological markers, while in controls, polyunsaturated fatty acids (PUFAs) showed stronger correlations. Conclusions: In cases, SFAs were associated with several immunological markers (CXCL10, IL-6, IL-9, IL-17, and CM-CSF) previously linked to the type 1 diabetes disease process. Findings indicate that fatty acids could have immunomodulatory potential in the early phase of the disease development, although causality between fatty acids and the immunological pathways remains to be explored. Trial registry number: NCT00179777.


Asunto(s)
Diabetes Mellitus Tipo 1 , Islotes Pancreáticos , Autoinmunidad , Estudios de Casos y Controles , Niño , Preescolar , Ácidos Grasos , Humanos , Lactante , Recién Nacido
3.
J Transl Autoimmun ; 3: 100055, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32743535

RESUMEN

Narcolepsy type 1, likely an immune-mediated disease, is characterized by excessive daytime sleepiness and cataplexy. The disease is strongly associated with human leukocyte antigen (HLA) DQB1∗06:02. A significant increase in the incidence of childhood and adolescent narcolepsy was observed after a vaccination campaign with AS03-adjuvanted Pandemrix influenza vaccine in Nordic and several other countries in 2010 and 2011. Previously, it has been suggested that a surface-exposed region of influenza A nucleoprotein, a structural component of the Pandemrix vaccine, shares amino acid residues with the first extracellular domain of the human OX2 orexin/hypocretin receptor eliciting the development of autoantibodies. Here, we analyzed, whether H1N1pdm09 infection or Pandemrix vaccination contributed to the development of autoantibodies to the orexin precursor protein or the OX1 or OX2 receptors. The analysis was based on the presence or absence of autoantibody responses against analyzed proteins. Entire OX1 and OX2 receptors or just their extracellular N-termini were transiently expressed in HuH7 cells to determine specific antibody responses in human sera. Based on our immunofluorescence analysis, none of the 56 Pandemrix-vaccinated narcoleptic patients, 28 patients who suffered from a laboratory-confirmed H1N1pdm09 infection or 19 Pandemrix-vaccinated controls showed specific autoantibody responses to prepro-orexin, orexin receptors or the isolated extracellular N-termini of orexin receptors. We also did not find any evidence for cell-mediated immunity against the N-terminal epitopes of OX2. Our findings do not support the hypothesis that the surface-exposed region of the influenza nucleoprotein A would elicit the development of an immune response against orexin receptors.

4.
Front Immunol ; 11: 468, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32265922

RESUMEN

Although gut bacterial dysbiosis is recognized as a regulator of beta-cell autoimmunity, no data is available on fungal dysbiosis in the children at the risk of type 1 diabetes (T1D). We hypothesized that the co-occurrence of fungal and bacterial dysbiosis contributes to the intestinal inflammation and autoimmune destruction of insulin-producing beta-cells in T1D. Fecal and blood samples were collected from 26 children tested positive for at least one diabetes-associated autoantibody (IAA, GADA, IA-2A or ICA) and matched autoantibody-negative children with HLA-conferred susceptibility to T1D (matched for HLA-DQB1 haplotype, age, gender and early childhood nutrition). Bacterial 16S and fungal ITS2 sequencing, and analyses of the markers of intestinal inflammation, namely fecal human beta-defensin-2 (HBD2), calprotectin and secretory total IgA, were performed. Anti-Saccharomyces cerevisiae antibodies (ASCA) and circulating cytokines, IFNG, IL-17 and IL-22, were studied. After these analyses, the children were followed for development of clinical T1D (median 8 years and 8 months). Nine autoantibody positive children were diagnosed with T1D, whereas none of the autoantibody negative children developed T1D during the follow-up. Fungal dysbiosis, characterized by high abundance of fecal Saccharomyces and Candida, was found in the progressors, i.e., children with beta-cell autoimmunity who during the follow-up progressed to clinical T1D. These children showed also bacterial dysbiosis, i.e., increased Bacteroidales and Clostridiales ratio, which was, however, found also in the non-progressors, and is thus a common nominator in the children with beta-cell autoimmunity. Furthermore, the progressors showed markers of intestinal inflammation detected as increased levels of fecal HBD2 and ASCA IgG to fungal antigens. We conclude that the fungal and bacterial dysbiosis, and intestinal inflammation are associated with the development of T1D in children with beta-cell autoimmunity.


Asunto(s)
Candida/fisiología , Diabetes Mellitus Tipo 1/inmunología , Heces/microbiología , Células Secretoras de Insulina/inmunología , Micosis/inmunología , Saccharomyces/fisiología , Adolescente , Anticuerpos Antifúngicos/sangre , Autoanticuerpos/sangre , Autoinmunidad , Niño , Preescolar , Diabetes Mellitus Tipo 1/epidemiología , Disbiosis , Heces/química , Femenino , Finlandia/epidemiología , Cadenas beta de HLA-DQ/genética , Humanos , Células Secretoras de Insulina/patología , Masculino , Micosis/epidemiología , beta-Defensinas/análisis
5.
Transl Psychiatry ; 10(1): 94, 2020 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-32179746

RESUMEN

Several lines of research support immune system dysregulation in psychotic disorders. However, it remains unclear whether the immunological marker alterations are stable and how they associate with brain glial cell function. This longitudinal study aimed at investigating whether peripheral immune functions are altered in the early phases of psychotic disorders, whether the changes are associated with core symptoms, remission, brain glial cell function, and whether they persist in a one-year follow-up. Two independent cohorts comprising in total of 129 first-episode psychosis (FEP) patients and 130 controls were assessed at baseline and at the one-year follow-up. Serum cyto-/chemokines were measured using a 38-plex Luminex assay. The FEP patients showed a marked increase in chemokine CCL22 levels both at baseline (p < 0.0001; Cohen's d = 0.70) and at the 12-month follow-up (p = 0.0007) compared to controls. The group difference remained significant (p = 0.0019) after accounting for relevant covariates including BMI, smoking, and antipsychotic medication. Elevated serum CCL22 levels were significantly associated with hallucinations (ρ = 0.20) and disorganization (ρ = 0.23), and with worse verbal performance (ρ = -0.23). Brain glial cell activity was indexed with positron emission tomography and the translocator protein radiotracer [11C]PBR28 in subgroups of 15 healthy controls and 14 FEP patients with serum CCL22/CCL17 measurements. The distribution volume (VT) of [11C]PBR28 was lower in patients compared to controls (p = 0.026; Cohen's d = 0.94) without regionally specific effects, and was inversely associated with serum CCL22 and CCL17 levels (p = 0.036). Our results do not support the over-active microglia hypothesis of psychosis, but indicate altered CCR4 immune signaling in early psychosis with behavioral correlates possibly mediated through cross-talk between chemokine networks and dysfunctional or a decreased number of glial cells.


Asunto(s)
Trastornos Psicóticos , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Quimiocina CCL22/metabolismo , Humanos , Estudios Longitudinales , Neuroglía/metabolismo
6.
Front Immunol ; 10: 907, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31134054

RESUMEN

Exercise and exercise-induced weight loss have a beneficial effect on overall health, including positive effects on molecular pathways associated with immune function, especially in overweight individuals. The main aim of our study was to assess how energy deprivation (i.e., "semi-starvation") leading to substantial fat mass loss affects the immune system and immunosuppression in previously normal weight individuals. Thus, to address this hypothesis, we applied a high-throughput systems biology approach to better characterize potential key pathways associated with immune system modulation during intensive weight loss and subsequent weight regain. We examined 42 healthy female physique athletes (age 27.5 ± 4.0 years, body mass index 23.4 ± 1.7 kg/m2) volunteered into either a diet group (n = 25) or a control group (n = 17). For the diet group, the energy intake was reduced and exercise levels were increased to induce loss of fat mass that was subsequently regained during a recovery period. The control group was instructed to maintain their typical lifestyle, exercise levels, and energy intake at a constant level. For quantification of systems biology markers, fasting blood samples were drawn at three time points: baseline (PRE), at the end of the weight loss period (MID 21.1 ± 3.1 weeks after PRE), and at the end of the weight regain period (POST 18.4 ± 2.9 weeks after MID). In contrast to the control group, the diet group showed significant (false discovery rate <0.05) alteration of all measured immune function parameters-white blood cells (WBCs), immunoglobulin G glycome, leukocyte transcriptome, and cytokine profile. Integrative omics suggested effects on multiple levels of immune system as dysregulated hematopoiesis, suppressed immune cell proliferation, attenuated systemic inflammation, and loss of immune cell function by reduced antibody and chemokine secretion was implied after intense weight loss. During the weight regain period, the majority of the measured immune system parameters returned back to the baseline. In summary, this study elucidated a number of molecular pathways presumably explaining immunosuppression in individuals going through prolonged periods of intense training with low-energy availability. Our findings also reinforce the perception that the way in which weight loss is achieved (i.e., dietary restriction, exercise, or both) has a distinct effect on how the immune system is modulated.


Asunto(s)
Ingestión de Energía/inmunología , Ejercicio Físico , Tolerancia Inmunológica , Pérdida de Peso/inmunología , Adulto , Proliferación Celular , Citocinas/sangre , Citocinas/genética , Dieta , Femenino , Humanos , Inmunoglobulina G/sangre , Recuento de Leucocitos , Leucocitos/inmunología , Transcriptoma/inmunología , Adulto Joven
7.
J Autoimmun ; 63: 68-75, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26227560

RESUMEN

Following the mass vaccinations against pandemic influenza A/H1N1 virus in 2009, a sudden increase in juvenile onset narcolepsy with cataplexy (NC) was detected in several European countries where AS03-adjuvanted Pandemrix vaccine had been used. NC is a chronic neurological disorder characterized by excessive daytime sleepiness and cataplexy. In human NC, the hypocretin-producing neurons in the hypothalamus or the hypocretin signaling pathway are destroyed by an autoimmune reaction. Both genetic (e.g. HLA-DQB1*0602) and environmental risk factors (e.g. Pandemrix) contribute to the disease development, but the underlying and the mediating immunological mechanisms are largely unknown. Influenza virus hemagglutinin is known to bind gangliosides, which serve as host cell virus receptors. Anti-ganglioside antibodies have previously been linked to various neurological disorders, like the Guillain-Barré syndrome which may develop after infection or vaccination. Because of these links we screened sera of NC patients and controls for IgG anti-ganglioside antibodies against 11 human brain gangliosides (GM1, GM2, GM3, GM4, GD1a, GD1b, GD2, GD3, GT1a, GT1b, GQ1b) and a sulfatide by using a line blot assay. Samples from 173 children and adolescents were analyzed: 48 with Pandemrix-associated NC, 20 with NC without Pandemrix association, 57 Pandemrix-vaccinated and 48 unvaccinated healthy children. We found that patients with Pandemrix-associated NC had more frequently (14.6%) anti-GM3 antibodies than vaccinated healthy controls (3.5%) (P = 0.047). Anti-GM3 antibodies were significantly associated with HLA-DQB1*0602 (P = 0.016) both in vaccinated NC patients and controls. In general, anti-ganglioside antibodies were more frequent in vaccinated (18.1%) than in unvaccinated (7.3%) individuals (P = 0.035). Our data suggest that autoimmunity against GM3 is a feature of Pandemrix-associated NC and that autoantibodies against gangliosides were induced by Pandemrix vaccination.


Asunto(s)
Autoanticuerpos/inmunología , Gangliósido G(M3)/inmunología , Cadenas beta de HLA-DQ/inmunología , Vacunas contra la Influenza/efectos adversos , Narcolepsia/etiología , Adolescente , Niño , Preescolar , Europa (Continente)/epidemiología , Humanos , Subtipo H1N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Gripe Humana/prevención & control , Vacunación Masiva/efectos adversos , Narcolepsia/inmunología
8.
Sci Transl Med ; 7(294): 294ra105, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-26136476

RESUMEN

The sleep disorder narcolepsy is linked to the HLA-DQB1*0602 haplotype and dysregulation of the hypocretin ligand-hypocretin receptor pathway. Narcolepsy was associated with Pandemrix vaccination (an adjuvanted, influenza pandemic vaccine) and also with infection by influenza virus during the 2009 A(H1N1) influenza pandemic. In contrast, very few cases were reported after Focetria vaccination (a differently manufactured adjuvanted influenza pandemic vaccine). We hypothesized that differences between these vaccines (which are derived from inactivated influenza viral proteins) explain the association of narcolepsy with Pandemrix-vaccinated subjects. A mimic peptide was identified from a surface-exposed region of influenza nucleoprotein A that shared protein residues in common with a fragment of the first extracellular domain of hypocretin receptor 2. A significant proportion of sera from HLA-DQB1*0602 haplotype-positive narcoleptic Finnish patients with a history of Pandemrix vaccination (vaccine-associated narcolepsy) contained antibodies to hypocretin receptor 2 compared to sera from nonnarcoleptic individuals with either 2009 A(H1N1) pandemic influenza infection or history of Focetria vaccination. Antibodies from vaccine-associated narcolepsy sera cross-reacted with both influenza nucleoprotein and hypocretin receptor 2, which was demonstrated by competitive binding using 21-mer peptide (containing the identified nucleoprotein mimic) and 55-mer recombinant peptide (first extracellular domain of hypocretin receptor 2) on cell lines expressing human hypocretin receptor 2. Mass spectrometry indicated that relative to Pandemrix, Focetria contained 72.7% less influenza nucleoprotein. In accord, no durable antibody responses to nucleoprotein were detected in sera from Focetria-vaccinated nonnarcoleptic subjects. Thus, differences in vaccine nucleoprotein content and respective immune response may explain the narcolepsy association with Pandemrix.


Asunto(s)
Anticuerpos Antivirales/inmunología , Reacciones Cruzadas/inmunología , Receptores de Orexina/inmunología , Proteínas de Unión al ARN/inmunología , Proteínas del Núcleo Viral/inmunología , Secuencia de Aminoácidos , Línea Celular , Niño , Humanos , Inmunidad , Inmunoglobulina G/sangre , Vacunas contra la Influenza/inmunología , Gripe Humana/inmunología , Gripe Humana/virología , Espectrometría de Masas , Datos de Secuencia Molecular , Narcolepsia/inmunología , Proteínas de la Nucleocápside , Receptores de Orexina/química , Péptidos/química , Péptidos/inmunología , Proteínas de Unión al ARN/química , Virus Reordenados/inmunología , Estaciones del Año , Alineación de Secuencia , Vacunación , Proteínas del Núcleo Viral/química
9.
PLoS One ; 9(12): e114361, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25501681

RESUMEN

BACKGROUND: Narcolepsy results from immune-mediated destruction of hypocretin secreting neurons in hypothalamus, however the triggers and disease mechanisms are poorly understood. Vaccine-attributable risk of narcolepsy reported so far with the AS03 adjuvanted H1N1 vaccination Pandemrix has been manifold compared to the AS03 adjuvanted Arepanrix, which contained differently produced H1N1 viral antigen preparation. Hence, antigenic differences and antibody response to these vaccines were investigated. METHODS AND FINDINGS: Increased circulating IgG-antibody levels to Pandemrix H1N1 antigen were found in 47 children with Pandemrix-associated narcolepsy when compared to 57 healthy children vaccinated with Pandemrix. H1N1 antigen of Arepanrix inhibited poorly these antibodies indicating antigenic difference between Arepanrix and Pandemrix. High-resolution gel electrophoresis quantitation and mass spectrometry identification analyses revealed higher amounts of structurally altered viral nucleoprotein (NP) in Pandemrix. Increased antibody levels to hemagglutinin (HA) and NP, particularly to detergent treated NP, was seen in narcolepsy. Higher levels of antibodies to NP were found in children with DQB1*06:02 risk allele and in DQB1*06:02 transgenic mice immunized with Pandemrix when compared to controls. CONCLUSIONS: This work identified 1) higher amounts of structurally altered viral NP in Pandemrix than in Arepanrix, 2) detergent-induced antigenic changes of viral NP, that are recognized by antibodies from children with narcolepsy, and 3) increased antibody response to NP in association of DQB1*06:02 risk allele of narcolepsy. These findings provide a link between Pandemrix and narcolepsy. Although detailed mechanisms of Pandemrix in narcolepsy remain elusive, our results move the focus from adjuvant(s) onto the H1N1 viral proteins.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/efectos adversos , Gripe Humana/prevención & control , Narcolepsia/etiología , Adolescente , Alelos , Animales , Formación de Anticuerpos , Antígenos Virales/efectos adversos , Antígenos Virales/análisis , Antígenos Virales/inmunología , Niño , Preescolar , Cadenas beta de HLA-DQ/genética , Cadenas beta de HLA-DQ/inmunología , Humanos , Inmunoglobulina G/inmunología , Vacunas contra la Influenza/análisis , Vacunas contra la Influenza/inmunología , Gripe Humana/genética , Gripe Humana/inmunología , Ratones Endogámicos NOD , Narcolepsia/genética , Narcolepsia/inmunología , Infecciones por Orthomyxoviridae/genética , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/prevención & control
10.
PLoS One ; 8(8): e68402, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23950869

RESUMEN

BACKGROUND: Narcolepsy cataplexy syndrome, characterised by excessive daytime sleepiness and cataplexy, is strongly associated with a genetic marker, human leukocyte antigen (HLA) DQB1*06:02. A sudden increase in the incidence of childhood narcolepsy was observed after vaccination with AS03-adjuvanted Pandemrix influenza vaccine in Finland at the beginning of 2010. Here, we analysed whether the coinciding influenza A H1N1pdm pandemic contributed, together with the Pandemrix vaccination, to the increased incidence of childhood narcolepsy in 2010. The analysis was based on the presence or absence of antibody response against non-structural protein 1 (NS1) from H1N1pdm09 virus, which was not a component of Pandemrix vaccine. METHODS: Non-structural (NS) 1 proteins from recombinant influenza A/Udorn/72 (H3N2) and influenza A/Finland/554/09 (H1N1pdm09) viruses were purified and used in Western blot analysis to determine specific antibody responses in human sera. The sera were obtained from 45 patients who fell ill with narcolepsy after vaccination with AS03-adjuvanted Pandemrix at the end of 2009, and from controls. FINDINGS: Based on quantitative Western blot analysis, only two of the 45 (4.4%) Pandemrix-vaccinated narcoleptic patients showed specific antibody response against the NS1 protein from the H1N1pdm09 virus, indicating past infection with the H1N1pdm09 virus. Instead, paired serum samples from patients, who suffered from a laboratory confirmed H1N1pdm09 infection, showed high levels or diagnostic rises (96%) in H1N1pdm virus NS1-specific antibodies and very high cross-reactivity to H3N2 subtype influenza A virus NS1 protein. CONCLUSION: Based on our findings, it is unlikely that H1N1pdm09 virus infection contributed to a sudden increase in the incidence of childhood narcolepsy observed in Finland in 2010 after AS03-adjuvanted Pandemrix vaccination.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/efectos adversos , Vacunas contra la Influenza/uso terapéutico , Gripe Humana/complicaciones , Gripe Humana/inmunología , Narcolepsia/etiología , Adolescente , Formación de Anticuerpos , Niño , Preescolar , Finlandia/epidemiología , Humanos , Subtipo H3N2 del Virus de la Influenza A/inmunología , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Pandemias , Pruebas Serológicas , Proteínas no Estructurales Virales/inmunología
11.
Vaccine ; 29(10): 1929-34, 2011 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-21236231

RESUMEN

We evaluated the effect of aging on the functional activity of naturally acquired anti-pneumococcal antibodies, the function of neutrophils in phagocytic killing of opsonized pneumococci, and the complement activity. Opsonic activities of antibodies to all tested pneumococcal serotypes were significantly lower and phagocytic killing of pneumococci by neutrophils was significantly impaired among the elderly, whereas the complement activity was slightly higher in the elderly than in the young adults. The reduced functional activity of serotype-specific antibodies and the compromised function of neutrophils in the opsonophagocytosis of pneumococci are likely to contribute to the increased susceptibility of the elderly to pneumococcal diseases.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Actividad Bactericida de la Sangre , Neutrófilos/inmunología , Fagocitosis , Streptococcus pneumoniae/inmunología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Envejecimiento/inmunología , Anticuerpos Antibacterianos/inmunología , Proteínas del Sistema Complemento/inmunología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proteínas Opsoninas/sangre , Proteínas Opsoninas/inmunología , Adulto Joven
12.
J Pharmacol Exp Ther ; 325(1): 236-47, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18174383

RESUMEN

Levosimendan (LS), a Ca(2+) sensitizer, is presently limited to i.v. administration. The dose-related pharmacodynamic effects of newly developed oral LS remain undetermined. We assessed the dose-response relationship of oral LS in nine normal and seven pacing-induced heart failure (HF), conscious, chronically instrumented mongrel dogs. Animals received a placebo capsule on day 1, and then LS was administered at single oral doses of 0.025 (day 2), 0.05 (day 4), and 0.1 (day 8) mg/kg. We serially measured plasma LS concentrations, hemodynamic, and left ventricular (LV) systolic and diastolic functional responses periodically until 12 h after oral LS. In both normal and HF, after three incremental dosages of oral LS, the peak plasma LS concentrations (34.6, 66.8, and 123.2 ng/ml in normal and 38.3, 71.5, and 137.4 ng/ml in HF) were achieved within 2 h in proportion to the dose, parallel to an increased LV contractility (normal, from 5.7 mm Hg/ml placebo to 8.2, 10.5, and 12.6 mm Hg/ml; HF, from 3.7 mm Hg/ml placebo to 5.7, 7.1, and 8.7 mm Hg/ml), and decreased time constant of LV relaxation (tau) (normal, from 28.8 ms of placebo to 25.6, 24.7, and 23.5 mm Hg/ml; HF, from 44.7 ms of placebo to 38.9, 36.4, and 34.6 ms). Compared with placebo, total systemic vascular resistance and mean left atrial pressure were significantly reduced after LS. In HF, oral LS caused a dose-dependent increase of LV-arterial coupling and mechanical efficiency. Heart rate increased only after 0.1 mg/kg LS in normal dogs. In conclusion, oral LS produces vasodilatation and dose-dependent augmentation in LV contractility and relaxation both in normal and HF.


Asunto(s)
Insuficiencia Cardíaca/tratamiento farmacológico , Hemodinámica/efectos de los fármacos , Hidrazonas/administración & dosificación , Piridazinas/administración & dosificación , Función Ventricular Izquierda/efectos de los fármacos , Administración Oral , Animales , Cardiotónicos/farmacología , Diástole/efectos de los fármacos , Perros , Relación Dosis-Respuesta a Droga , Hidrazonas/farmacocinética , Hidrazonas/farmacología , Contracción Miocárdica/efectos de los fármacos , Piridazinas/farmacocinética , Piridazinas/farmacología , Simendán , Vasodilatación/efectos de los fármacos
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