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1.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(6): 885-890, 2023 Jun 06.
Artículo en Chino | MEDLINE | ID: mdl-37357208

RESUMEN

Objective: To investigate the clinical value of serum glypican-3 (GPC3) detection in predicting recurrence of primary hepatocellular carcinoma (HCC). Methods: Through univariate and multivariate logistic regression analysis, the patients pathologically diagnosed with HCC in our hospital from March 2019 to January 2021 were enrolled as the experimental group (n=113), and patients with follow-up time longer than 6 months were included in the prognosis group(n=64). At the same time,20 healthy individuals and 20 individuals with benign liver disease from the physical examination center were enrolled by simple random sampling as control group (n=40). The serum GPC3 and alpha-fetoprotein (AFP) levels were respectively detected by ELISA and chemiluminescence. Then, the study explored the influential factors of the recurrence in HCC patients and constructed the HCC-GPC3 recurrence predicting model by logistic regression. Results: In the research, the sensitivity of GPC3 for the diagnosis of HCC was 61.95% (70/113) and AFP was 52.21% (59/113), meanwhile, the specificity of GPC3 could reach 87.50% (35/40) and AFP was 90.00% (36/40),respectively; The serum GPC3 levels of HCC patients with progressive stage, tumor size≥3 cm, vascular cancer thrombosis and portal venous thromboembolism were significantly higher than that of HCC patients with early stage, tumor size<3 cm, vascular cancer thrombosis and portal venous thromboembolism (Z=2.677, 2.848, 2.995, 2.252, P<0.05), independent of different ages, presence or absence of ascites, peritoneal metastasis, cirrhosis, intrahepatic metastasis (Z=-1.535, 1.011, 0.963, 0.394, 1.510, P>0.05), respectively. Univariate analysis showed that there were no statistically significant differences between the recurrence group and the non-recurrence group in terms of different age, tumor size, presence or absence of vascular cancer thrombosis, ascites, peritoneal metastasis, cirrhosis and AFP levels (χ2=2.012, 0.119, 2.363, 1.041, 0.318, 0.360, Z=0.748, P>0.05); The ratio of those with the progressive stage, portal venous thromboembolism and intrahepatic metastasis and GPC3 levels were all higher in the recurrence group than in the non-recurrence group (χ2=4.338, 11.90, 4.338, Z=2.805, P<0.05).Including the above risk factors in the logistic regression model, the logistic regression analysis showed that the stage, the presence of portal venous thromboembolism,intrahepatic metastasis and GPC3 levels were correlated with the prognosis recurrence of HCC patients (Wald χ2=4.421, 5.681, 4.995, 4.319, P<0.05), and the HCC-GPC3 recurrence model was obtained as: OcScore=-2.858+1.563×[stage]+1.664×[intrahepatic metastasis]+2.942×[ portal venous thromboembolism]+0.776×[GPC3]. According to the receiver operating characteristic curve(ROC), the area under the curve(AUC)of the HCC-GPC3 prognostic model was 0.862, which was better than that of GPC3 alone (AUC=0.704). The cut-off value of model SCORE was 0.699 (the cut-off value of GPC3 was 0.257 mg/L), furthermore, the total sensitivity and specificity of model were 83.3% and 82.4%, which were better than those of GPC3(60.0% and 79.4%).Kaplan-Meier showed that the median PFS was significantly shorter in HCC patients with high GPC3 levels (≥0.257 mg/L) and high values of the model SCORE (≥0.700) (χ2=12.73, 28.16, P<0.05). Conclusion: Besides diagnosing of HCC, GPC3 can may be an independent risk indicator for the recurrence of HCC and can more efficiently predicting the recurrence of HCC patients when combined with the stage, the presence or absence of intrahepatic metastasis and portal venous thromboembolism.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Neoplasias Peritoneales , Tromboembolia Venosa , Humanos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/diagnóstico , alfa-Fetoproteínas/análisis , Biomarcadores de Tumor , Glipicanos , Ascitis , Cirrosis Hepática
2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(12): 1468-1474, 2021 Dec 06.
Artículo en Chino | MEDLINE | ID: mdl-34963245

RESUMEN

Objective: To discuss the diagnostic value of calcitonin(CT), carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), pro-gastrin releasing peptide (Pro-GRP) and chromogranin A (CgA) in the identification of medullary thyroid carcinoma (MTC). Methods: The CT levels in 105 cases of MTC, 50 cases of papillary thyroid carcinoma, 10 cases of thyroid follicular carcinoma, 5 cases of undifferentiated thyroid carcinoma, 50 cases of benign thyroid diseases, 30 cases of non-thyroid malignant tumors and 50 cases of healthy controls were measured from February 2017 to August 2019 at the Department of Clinical Laboratory, Cancer Hospital affliated to Fudan University. Additionally, 79 cases of MTC, 30 cases of non-MTC thyroid malignant tumors and 30 healthy controls were selected for the measurement of CEA, NSE, Pro-GRP and CgA levels. The receiver operating curve was utilized to clarify the area under the curve (AUC), sensitivity, and specificity of each indicator to distinguish between different groups. Results: The medians of CT concentrations in the group of MTC patients was 607.2 (152.5,2 777.5)pg/ml, which was statistically significantly higher than that of the subjects in the group of papillary thyroid carcinoma 1.48 (0.5,2.91)pg/ml, follicular thyroid carcinoma 1.90 (0.82,2.99)pg/ml, undifferentiated thyroid carcinoma 0.50 (0.50,4.93)pg/ml, benign thyroid disease 1.30 (0.50,2.79)pg/ml, non-thyroid malignancies 1.36 (0.50,2.89)pg/ml and healthy controls 2.05 (0.89,3.18)pg/ml. The sensitivity, specificity and AUC of CT to distinguish MTC vs. non-MTC patients was 96.2%, 99.3% and 0.99, respectively. The maximum diameter (>1 cm, P=0.001, OR=15.74) and number (>1, P=0.04, OR=3.4) of nodules were two independent risk factors for elevated CT. CEA (AUC=0.94), NSE (AUC=0.65), Pro-GRP (AUC=0.94) and CgA (AUC=0.83) could all distinguish MTC vs. non-MTC thyroid malignancies. The AUC, sensitivity and specificity by combining CT, CEA, NSE, Pro-GRP and CgA to differentiate MTC vs. non-MTC thyroid malignancies was 1, 100% and 100%, respectively. Conclusions: CT, CEA, NSE, Pro-GRP and CgA may be helpful for the auxiliary diagnosis of MTC. The combination of these indicators in the diagnosis of MTC has high sensitivity and specificity.


Asunto(s)
Carcinoma Neuroendocrino , Neoplasias de la Tiroides , Biomarcadores de Tumor , Cromogranina A , Humanos , Laboratorios Clínicos
3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(9): 998-1002, 2020 Sep 06.
Artículo en Chino | MEDLINE | ID: mdl-32907292

RESUMEN

Objective: To investigate the clinical value of glypican-3 (GPC3) detection in the diagnosis and therapy-monitoring of primary hepatocellular carcinoma (HCC). Methods: From March 2018 to May 2019, the patients with HCC were enrolled as the experimental group(n=166)from Fudan University Shanghai Cancer Centre, while the specimens from health control group(n=94) and benign control group (n=50) were analyzed. The serum of GPC3 and alpha fetoprotein (AFP)levels were respectively detected by ELISA and chemiluminescence. GPC3 detections combined with AFP etc. in accuracy of HCC diagnosis were explored by using Logistic regression analysis. Results: The serum GPC3 level in patients with HCC [0.210 (0.048, 0.801)mg/L] [Median (quartile Q1, Q3)] was significantly higher than those in healthy controls [0.029(0.019, 0.052)mg/L] and benign controls [0.033(0.021, 0.043) mg/L] (Z=-7.69, P<0.001).The serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and AFP were significantly different among the three groups (Z=-7.02, -6.85, -8.36 respectively, P<0.001). Among the serological indicators, it was related to ALT and AST (Z=-3.77, -4.09 respectively, P<0.001).The Cut-off level of GPC3 was determined as 0.077 mg/L by ROC curve. The sensitivity of the combined detection of serum GPC3 with AFP for HCC was up to 87.82%, the specificity was 77.86%, the negative predictive value was 84.29%, and the positive predictive value was 82.53%.The HCC-GPC3 model was constructed by using Logistic regression analysis. The area under the ROC curve was 0.882, the total sensitivity was 91.10%, and the total specificity was 72.73%. Further analysis showed that the serum GPC3 of patients with HCC was significantly lower [0.454(0.019, 0.286) mg/L] than that before surgery[0.608(0.039, 0.554)mg/L](Z=-7.32, P<0.001). Conclusion: The detection of serum GPC3 can be applied to aid diagnosis and therapy-monitoring of HCC.The combination of GPC3 and AFP can improve the diagnostic efficiency of HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas/diagnóstico , Biomarcadores de Tumor , China , Glipicanos , Humanos
4.
J Eur Acad Dermatol Venereol ; 33(1): 178-184, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30223307

RESUMEN

BACKGROUND: Currently, many laboratories have switched the traditional screening algorithm (TSA) to reverse screening algorithm (RSA) for the efficiencies in high-volume syphilis screening. However, confusions have been arisen regarding this paradigm shift. OBJECTIVE: To compare the performance of two algorithms with head-to-head mode. METHODS: Sera screening for syphilis were tested in parallel with chemiluminescence immunoassay (CIA) and toluidine red unheated serum test (TRUST). CIA-reactive sera from the RSA were reflexively tested with TRUST and confirmed with Treponema pallidum particle agglutination assay (TPPA), while the TRUST-reactive serology from the TSA were afterwards tested with TPPA. RESULTS: A total of 110 663 serum samples were screened. The RSA identified 2259 (2.0%) CIA-reactive results, of which 377 (16.7%) showed TPPA nonreactive results, while the TSA identified 934 (0.8%) TRUST-reactive results, of which 67 (7.2%) showed TPPA-nonreactive results. Among the 2259 CIA-reactive results, 1392 (61.6%) were TRUST-nonreactive, of which 350 (25.1%) were TPPA-nonreactive. A total of 182 sera from the 350 TPPA-nonreactive sera were further tested by a second CIA (VITROS Syphilis TPA, VITROS TPA), of which 155 (85.2%) were nonreactive and 27 (14.8%) were reactive. The 27 VITROS TPA-reactive sera were further tested with a treponemal Western blot assay (Euroimmun IgG Western Blot, EuroWB), of which 11 (41%) were indeterminate, 6 (22%) were nonreactive and 10 (37%) were reactive. Among the 10 EuroWB-reactive sera, two seroconverted to TPPA 1:80+/- after 1-year follow-up. Of 867 CIA-reactive/TRUST-reactive results, 27 (3.1%) were TPPA-nonreactive. CONCLUSIONS: The RSA identified more patients with reactive treponemal serology. However, it also yielded an increased likely false-reactive rate compared with the TSA, especially those results with low index values and TRUST-nonreactive serology, were necessary to retest with a second treponemal test. Further testing results with TPPA, VITROS TPA and EuroWB suggested the false-reactive CIA screening results and the likely false-nonreactive TPPA results when the reactive treponemal results screened with RSA were to be identified.


Asunto(s)
Algoritmos , Serodiagnóstico de la Sífilis , Sífilis/sangre , Sífilis/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Pruebas de Aglutinación , Anticuerpos Antibacterianos/sangre , Compuestos Azo , Western Blotting , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Humanos , Mediciones Luminiscentes , Masculino , Tamizaje Masivo/métodos , Persona de Mediana Edad , Treponema pallidum/inmunología
5.
Shock ; 14(6): 652-6, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11131917

RESUMEN

This study was designed to investigate the effect of a calcium sensitizer on the Ca2+ sensitivity of myocardial fibers in endotoxic shock rats. Right ventricular papillary muscles from sham shock or endotoxic shock rats were skinned by incubation in saponin solution. Forces of the skinned muscles were recorded when they were activated sequentially by different pCa (-log[Ca2+]) activating solutions with or without positive inotropic agents. Tension-pCa relationship curve of skinned fibers delineated the affinity of troponin C(TnC) for Ca2+ and the medium value pCa50 (pCa required for producing 50% of maximal Ca2+-activated tension) was taken as the quantitative index of Ca2+ sensitivity of TNC. It was found that the maximal Ca2+ activated tension (Tmax) was lower, tension-pCa relationship curve was shifted rightward, and the pCa50 was reduced significantly in endotoxic shock group compared with that of sham shock group. Milrinone could not counteract the above abnormalities. However, when skinned right ventricular papillary fibers from endotoxic shock rats were dealt with activating solutions containing 1 x 10(-5) M MCI-154, the Tmax was significantly increased, the tension-pCa relationship curve was shifted leftward. The pCa50 in MCI-154 group was increased to an extent similar to that of sham shock group and markedly higher than the values of endotoxic shock group and milrinone group. Furthermore, such effects of MCI-154 were concentration dependent. It can been concluded that the sensitivity of cardiac contractile proteins to Ca2+ in endotoxic shock rats is decreased. MCI-154, a calcium sensitizer, can significantly reverse the decreased sensitivity and increase Tmax of myocardial muscles from endotoxic shock rats.


Asunto(s)
Calcio/farmacología , Músculos Papilares/efectos de los fármacos , Músculos Papilares/fisiopatología , Piridazinas/farmacología , Choque Séptico/tratamiento farmacológico , Choque Séptico/fisiopatología , Animales , Calcio/metabolismo , Cardiotónicos/administración & dosificación , Cardiotónicos/farmacología , Relación Dosis-Respuesta a Droga , Resistencia a Medicamentos , Femenino , Técnicas In Vitro , Masculino , Fibras Musculares Esqueléticas/efectos de los fármacos , Fibras Musculares Esqueléticas/fisiología , Contracción Miocárdica/efectos de los fármacos , Piridazinas/administración & dosificación , Ratas , Ratas Wistar , Troponina C/metabolismo
6.
Shock ; 13(6): 459-63, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10847633

RESUMEN

This study was designed to observe the effects of MCI-154, a calcium sensitizer, on cardiac dysfunction after endotoxic shock in rabbits. Ten hours after the rabbits were given injection of 1.0 mg/kg endotoxin (Escherichia coli, O111:B4) via marginal ear veins, 0.1 mg/kg MCI-154 was injected intravenously and then 50 mL/kg normal saline (NS) + 0.1 mg/kg MCI-154 was infused continuously at a rate of 0.7 mL/min. During this process, the parameters of cardiac function were measured. It was found that 10 h after the endotoxin injection, heart rate (HR) was increased significantly while the mean arterial blood pressure (MAP), left ventricular systolic pressure (LVSP), isovolumetric pressure (IP), myocardial contractility (MC), and the area of p-dp/dt(max) vector loop (Lo) all were markedly decreased. Treatment with 50 mL/kg NS alone had slight effects on these parameters. On the contrary, LVSP, IP, MC, and Lo all were increased significantly while HR was not obviously changed and left ventricular end-diastolic pressure (LVEDP) was reduced remarkably following MCI-154 administration in endotoxic shock rabbits. The parameters of myocardial contractility were improved nearly to the values in sham shock group and were markedly higher than that in NS alone-treated group. It can be concluded that MCI-154 can exert significant therapeutic effects on cardiac dysfunction after endotoxic shock, for it improves cardiac function, dilates peripheral blood vessels, and slightly affects HR.


Asunto(s)
Calcio/fisiología , Cardiopatías/prevención & control , Hemodinámica/efectos de los fármacos , Contracción Miocárdica/efectos de los fármacos , Piridazinas/uso terapéutico , Choque Séptico/complicaciones , Animales , Evaluación Preclínica de Medicamentos , Femenino , Cardiopatías/etiología , Pruebas de Función Cardíaca/efectos de los fármacos , Lipopolisacáridos/toxicidad , Masculino , Proyectos Piloto , Piridazinas/farmacología , Conejos , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Izquierda/prevención & control , Función Ventricular Izquierda/efectos de los fármacos
7.
Acta Pharmacol Sin ; 21(9): 824-9, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11501165

RESUMEN

AIM: To observe the effects of MCI-154, a calcium sensitizer, on cardiac function after endotoxic shock. METHODS: The rabbits were intravenously injected with MCI-154 0.1 mg.kg-1 at 10 h after the administration of endotoxin 1.0 mg.kg-1, followed by a continuous infusion of normal saline (NS) 50 mL.kg-1 + MCI-154 0.1 mg.kg-1. During this process, the parameters of cardiac function were measured. RESULTS: Ten hours after the endotoxin injection, heart rate (HR) increased noticeably while the mean arterial blood pressure (MAP), left ventricular systolic pressure (LVSP), isovolumetric pressure (IP), myocardial contractility (MC), and the area of p-dp/dtmax vector loop (Lo) were all markedly decreased. Treatment with NS 50 mL.kg-1 alone had slight effects on these parameters. LVSP, IP, MC, and Lo were all markedly increased while HR did not obviously change and left ventricular end-diastolic pressure (LVEDP) was reduced markedly following MCI-154 administration in endotoxic shock rabbits. The parameters of MC were improved nearly to the same values as in sham shock group and were markedly higher than in NS treated group. CONCLUSION: MCI-154 exerts remarkable therapeutic effects on cardiac dysfunction after endotoxic shock.


Asunto(s)
Cardiotónicos/farmacología , Piridazinas/farmacología , Choque Séptico/fisiopatología , Función Ventricular Izquierda/efectos de los fármacos , Animales , Calcio/fisiología , Endotoxinas , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Masculino , Conejos , Distribución Aleatoria , Choque Séptico/inducido químicamente
8.
Acta Pharmacol Sin ; 21(9): 830-4, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11501166

RESUMEN

AIM: To investigate the effect of MCI-154 on calcium sensitivity of myocardial contractile system in endotoxemic rats. METHODS: Skinned right ventricular papillary muscles from endotoxemic rats were prepared by saponin 500 mg/L. Forces of the skinned muscles were recorded when they were activated sequentially by different concentrations of Ca2+ with or without cardiotonic agents. The tension-pCa relationship and pCa50 of the skinned fibers were taken as the index of Ca2+ sensitivity of myocardial contractile system. RESULTS: The maximal Ca(2+)-activated tension (Tmax) was lower, and pCa50 was reduced in endotoxemia group as compared with those in sham control group. Milrinone 50 mumol/L could not counteract the above abnormalities. However, after MCI-154 10 mumol/L was added, the Tmax and pCa50 were increased to an extent similar to that of sham control group and significantly higher than those of endotoxemia group and endotoxemia + milrinone group. Furthermore, such effects of MCI-154 were concentration-dependent. CONCLUSION: The Ca2+ sensitivity of cardiac contractile system in endotoxemic rats is decreased. MCI-154 can reverse the decreased sensitivity and increase Tmax of myocardial muscles from endotoxemic rats.


Asunto(s)
Cardiotónicos/farmacología , Contracción Miocárdica/efectos de los fármacos , Piridazinas/farmacología , Choque Séptico/fisiopatología , Animales , Calcio/fisiología , Endotoxinas , Femenino , Técnicas In Vitro , Masculino , Músculos Papilares/fisiopatología , Distribución Aleatoria , Ratas , Ratas Wistar , Choque Séptico/inducido químicamente
9.
Chin J Dent Res ; 1(2): 22-5, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10557190

RESUMEN

OBJECTIVE: Dental anatomy is one of the most important basic courses in the education of dentistry. The deep understanding of both the external and internal morphologic characteristics is very important to the teaching, research and clinical practice of dentistry. METHODS: In the present study, 32 permanent teeth from the skull specimen of a young man were individually embedded in black fluid resin, each in special containers. They were ground by a numerically-controlled grinding machine at intervals of 0.2 mm per layer. A distinct outline of the tooth could be seen on every section. Black and white photographs were taken and scanned into a computer by a film-scanner to obtain sequences of two-dimensional images of the tooth sections. After pattern recognition, all of the images of each tooth were piled up at intervals of 0.2 mm by the technique of computerized reconstruction. RESULTS: The three-dimensional stereo tooth models were built up from two-dimensional data. On the basis of those models, computer graphic techniques were used to highlight, smooth, and shade the teeth. These digital teeth and dentitions could function as a series of computerized teaching models. Their high resolution and accuracy could meet the basic demands of dentistry. CONCLUSIONS: The present study developed new techniques of model preparation, image input, and 3-D reconstruction. These digital teeth and dentitions provide an important foundation for the application of computer imaging, CAD/CAM, computer-assisted instruction, and virtual reality in dentistry.


Asunto(s)
Educación en Odontología/métodos , Procesamiento de Imagen Asistido por Computador , Modelos Dentales , Diente/anatomía & histología , Anatomía Transversal , Diseño Asistido por Computadora , Instrucción por Computador , Humanos , Masculino , Modelos Educacionales , Fotografía Dental
10.
Shock ; 7(1): 60-4, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8989838

RESUMEN

Many studies have demonstrated that thyrotropin-releasing hormone (TRH) produces various beneficial effects in the treatment of shock. TRH has been proposed to reverse the cardiovascular depression of endogenous opioid peptides. Nevertheless, it remains unknown whether opioid receptors are truly involved in this process. We designed experiments to study the importance of delta and kappa opioid receptors in the beneficial effects of TRH in hemorrhagic shock in rabbits and on opiate receptors following hemorrhagic shock in rats. The results indicated that TRH (50 micrograms, i.c.v.) significantly improved the mean arterial pressure (MAP), left ventricular systolic pressure (LVSP), and the maximal rate of ventricular systolic pressure changes (+/- dp/dtmax) during hemorrhagic shock in rabbits. This TRH effect was abolished by pretreatment with ICI174,864 (50 micrograms, i.c.v.), a highly selective delta opioid receptor antagonist, but not by pretreatment with nor-binaltorphimine (Nor-BNI, 50 micrograms, i.c.v.), a highly selective kappa opioid receptor antagonist. The maximal binding capacity (Bmax) of brain delta and kappa opioid receptors significantly increased following hemorrhagic shock, but the receptor affinity (Kd) did not change. TRH (5 mg/kg, i.v.) decreased the number (Bmax) of brain delta opioid receptors significantly, but it did not influence the receptor affinity. TRH did not influence the Bmax or affinity of brain kappa opioid receptors. These findings suggest that opioid receptors play an important role in mediating the antishock property of TRH. TRH-induced down-regulation of the number of brain opioid receptors may be one of the important mechanisms by which TRH exercises its protective effects in the treatment of shock.


Asunto(s)
Receptores Opioides delta/fisiología , Receptores Opioides kappa/fisiología , Choque Hemorrágico/fisiopatología , Hormona Liberadora de Tirotropina/fisiología , Animales , Presión Sanguínea/efectos de los fármacos , Encefalina Leucina/análogos & derivados , Encefalina Leucina/farmacología , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Cinética , Masculino , Naltrexona/análogos & derivados , Naltrexona/farmacología , Antagonistas de Narcóticos/farmacología , Conejos
11.
Shock ; 3(6): 430-3, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7656067

RESUMEN

Although studies have indicated that thyrotropin-releasing hormone (TRH) produces various beneficial effects following low flow conditions, it remains unknown whether this agent has any salutary effect on myocardial alpha- and beta-adrenergic and dopaminergic (DA) receptors following hemorrhagic shock. To study this, rats (220-280 g) were bled to a mean arterial pressure of 40 mmHg and maintained for 1.5 h following shock. TRH or an equivalent volume of normal saline was administered. Receptor binding assay was carried out in myocardial plasma membrane preparations at 15 and 45 min after TRH administration. The results indicate that the maximal binding capacity (Bmax) of myocardial alpha- and beta-adrenergic receptors and their affinity decreased significantly following hemorrhage. The Bmax of DA receptors was also reduced, while the affinity was not significantly affected by hemorrhagic insult. Administration of TRH (5 mg/kg body wt) at 1.5 h after the onset of hemorrhage, however, markedly increased the Bmax of myocardial beta-adrenergic and DA receptors. The decreased affinity of beta-adrenoceptors observed in hemorrhaged animals was also improved with TRH treatment. TRH did not, however, significantly affect the altered Bmax and affinity of alpha-adrenoceptors following hemorrhagic shock. These results suggest that TRH-induced upregulation of beta-adrenoceptor and DA receptor binding capacity and the enhanced affinity of beta-adrenoceptors may be one of the mechanisms by which TRH produces the beneficial effects following hemorrhagic shock.


Asunto(s)
Miocardio/metabolismo , Receptores Adrenérgicos/metabolismo , Receptores Dopaminérgicos/metabolismo , Choque Hemorrágico/metabolismo , Hormona Liberadora de Tirotropina/farmacología , Animales , Membrana Celular/metabolismo , Femenino , Masculino , Miocardio/patología , Prazosina/farmacología , Ensayo de Unión Radioligante , Ratas , Ratas Wistar , Receptores Adrenérgicos/efectos de los fármacos , Receptores Dopaminérgicos/efectos de los fármacos
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