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Prazosina , Angústia Psicológica , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Prazosina/administração & dosagem , Prazosina/uso terapêutico , Masculino , Adulto , Pessoa de Meia-Idade , Antagonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , FemininoRESUMO
Arterial stiffness, a prominent hallmark of ageing arteries, is a predictor of all-cause mortality. Strategies for promoting healthy vascular ageing are encouraged. Here we conducted a pilot study to evaluate the potential effects of low-dose Terazosin on arterial stiffness. We enrolled patients aged over 40 with elevated arterial stiffness, defined as a brachial-ankle pulse wave velocity (baPWV) ≥1400 cm/s, who were administered Terazosin (0.5 and 1.0 mg/day) from December 2020 to June 2023. Treatment responses were assessed every 3 months. Linear regression analysis was used to characterise the improvement. We matched cases who took Terazosin for 1 year with Terazosin-free controls using propensity score matching (PSM). Our findings demonstrate that Terazosin administration significantly affected arterial stiffness. (1) Arterial stiffness significantly improved (at least a 5% reduction in baPWV) in 50.0% of patients at 3 months, 48.6% at 6 months, 59.3% at 9 months, and 54.4% at 12 months, respectively. (2) Those with higher baseline baPWV and hypertension exhibited a significantly reduced risk of non-response. (3) Terazosin was associated with a reduction of baPWV at 1-year follow-up (linear regression: ß = -165.16, p < 0.001). This pilot study offers valuable insights into the potential significance of Terazosin in improving arterial stiffness and paves the way for future randomised clinical trials in combating vascular ageing.
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Prazosina , Análise de Onda de Pulso , Rigidez Vascular , Humanos , Rigidez Vascular/efeitos dos fármacos , Projetos Piloto , Masculino , Feminino , Idoso , Prazosina/análogos & derivados , Prazosina/farmacologia , Prazosina/administração & dosagem , Prazosina/uso terapêutico , Pessoa de Meia-Idade , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Índice Tornozelo-BraçoRESUMO
BACKGROUND: The isometric handgrip (IHG) test is commonly used to detect sympathetic autonomic dysfunction. Tamsulosin, approved for the management of symptomatic benign prostatic hyperplasia (BPH), acts as an antagonist for α1-adrenergic receptors (α1-AR), whereas prazosin, an α1 receptor blocker, being less selective than tamsulosin, is used as an antihypertensive agent clinically. Our objective was to investigate if there is a distinction in blood pressure (BP) increase during IHG exercise between individuals with essential hypertension taking tamsulosin compared to those taking prazosin. MATERIALS AND METHODS: A cross-sectional observational study was performed on 50 subjects receiving tablet prazosin and 47 subjects receiving tamsulosin, who were asked to undergo an IHG test. Pre- and posttest BP was recorded for both the groups, and the difference in diastolic BP (DBP) (delta DBP) was compared between the groups and to their respective baseline values. RESULTS: Post-IHG test, mean DBP was found to be 93.98 ± 9.13 mm Hg in the prazosin group and 101.00 ± 12.05 mm Hg in the tamsulosin group, respectively. The change of delta DBP in the tamsulosin group was significant, but the prazosin group showed an insignificant rise in DBP. CONCLUSION: Prazosin, being less selective than tamsulosin in terms of α1 receptor antagonism, showed suppression of BP during IHG. Tamsulosin demonstrates high selectivity for prostatic receptors while showing minimal affinity for vascular receptors. As a result, its impact on BP is expected to be minimal.
Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1 , Pressão Sanguínea , Força da Mão , Hipertensão , Prazosina , Hiperplasia Prostática , Tansulosina , Humanos , Masculino , Estudos Transversais , Hiperplasia Prostática/tratamento farmacológico , Hiperplasia Prostática/fisiopatologia , Prazosina/farmacologia , Prazosina/uso terapêutico , Prazosina/administração & dosagem , Tansulosina/uso terapêutico , Pessoa de Meia-Idade , Antagonistas de Receptores Adrenérgicos alfa 1/uso terapêutico , Antagonistas de Receptores Adrenérgicos alfa 1/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Força da Mão/fisiologia , Idoso , Anti-Hipertensivos/uso terapêutico , ÍndiaRESUMO
PURPOSE: The present study aims to assess and compare the effects of carvedilol and terazosin plus enalapril on lower urinary tract symptoms (LUTS), the urine flow, and blood pressure (BP) in patients with moderate hypertension (HTN) and benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: In this randomized crossover trial, a total of 40 men with HTN and LUTS symptoms were enrolled. The first group was treated with carvedilol, and the second one received terazosin plus enalapril. After eight weeks of treatment, the patients experienced a one-month washout period, and the treatments changed and continued for eight weeks. To diagnose BPH in the study, the international prostate symptom score (IPSS) questionnaire was used. Moreover, the prostate-specific antigen (PSA), the post-void residual (PVR) urine volume, and the maximum urinary flow rate (Q-max using the uroflowmetry test) were measured. RESULTS: Effect assessment results in this crossover trial illustrated neither carryover effects nor significant treatment effects on all primary outcomes (P > 0.05). Moreover, the results for the period effect indicated a significant reduction in BP (systolic and diastolic), PVR, and IPSS, yet a significant raise in Qmax. CONCLUSION: The effects of carvedilol are similar to those of the combination of terazosin and enalapril in patients with moderate HTN and BPH in controlling LUTS. Carvedilol could be used as an appropriative drug in patients with moderate HTN and cardiac problems with LUTS of BPH. Further studies are recommended to be conducted to investigate and compare the efficacy of carvedilol with that of other alpha-blockers with a larger sample size and over a longer period of time.
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Antagonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , Anti-Hipertensivos/administração & dosagem , Carvedilol/administração & dosagem , Enalapril/administração & dosagem , Prazosina/análogos & derivados , Idoso , Estudos Cross-Over , Quimioterapia Combinada , Humanos , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Prazosina/administração & dosagem , Hiperplasia Prostática/complicações , Método Simples-CegoRESUMO
Importance: Parkinson disease (PD) is a common neurodegenerative disease. A treatment that prevents or delays development of PD is a critical unmet need. Terazosin and closely related drugs were recently discovered to enhance glycolysis and reduce PD progression in animal models and human clinical databases. Objective: To determine whether use of terazosin, doxazosin, and alfuzosin is associated with a decreased risk of developing PD. Design, Setting, and Participants: This cohort study used active comparator control and propensity score-matched data from Danish nationwide health registries, including the Danish National Prescription Registry, the Danish National Patient Registry, and the Danish Civil Registration System, from January 1996 to December 2017 and data from the Truven Health Analytics MarketScan database from January 2001 to December 2017. Men without PD who newly initiated terazosin/doxazosin/alfuzosin therapy or tamsulosin therapy, which is used for a similar indication (benign prostatic hyperplasia or unspecified urinary problems) but does not enhance glycolysis, and had at least 1 year of follow-up after medication start were included. In Denmark, the database included all residents, while the Truven database is a compilation of insurance claims across the US. Data were analyzed from February 2019 to July 2020. Exposures: Patients who used terazosin/doxazosin/alfuzosin vs tamsulosin. Additional dose-response analyses were carried out. Main Outcomes and Measures: Differences in the hazard of developing PD identified by diagnoses or use of PD-specific medications between patients who ever used terazosin/doxazosin/alfuzosin or tamsulosin. Results: A cohort of 52â¯365 propensity score-matched pairs of terazosin/doxazosin/alfuzosin and tamsulosin users were identified in the Danish registries, of which all were male and the mean (SD) age was 67.9 (10.4) years, and 94â¯883 propensity score-matched pairs were identified in the Truven database, of which all were male and the mean (SD) age was 63.8 (11.1) years. Patients in the Danish cohort who used terazosin/doxazosin/alfuzosin had a hazard ratio (HR) for developing PD of 0.88 (95% CI, 0.81-0.98), and patients in the Truven cohort had an HR of 0.63 (95% CI, 0.58-0.69). There was a dose-response association with short-duration, medium-duration, and long-duration use of terazosin/doxazosin/alfuzosin users having a decreasing HR in both the Danish cohort (short: HR, 0.95; 95% CI, 0.84-1.07; medium: HR, 0.88; 95% CI, 0.77-1.01; long: HR, 0.79; 95% CI, 0.66-0.95) and Truven cohort (short: HR, 0.70; 95% CI, 0.64-0.76; medium: HR, 0.58; 95% CI, 0.52-0.64; long: HR, 0.46; 95% CI, 0.36-0.57). Conclusions and Relevance: These data suggest that users of terazosin/doxazosin/alfuzosin are at lower hazard of developing PD compared with users of tamsulosin. Future work is needed to further assess this association.
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Antagonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , Glicólise/efeitos dos fármacos , Doença de Parkinson/epidemiologia , Doença de Parkinson/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Bases de Dados Factuais/tendências , Dinamarca/epidemiologia , Doxazossina/administração & dosagem , Feminino , Seguimentos , Glicólise/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico , Doença de Parkinson/metabolismo , Prazosina/administração & dosagem , Prazosina/análogos & derivados , Quinazolinas/administração & dosagem , Sistema de Registros , Fatores de Risco , Tansulosina/administração & dosagem , Estados Unidos/epidemiologiaRESUMO
This study aimed to construct a transdermal iontophoresis delivery system for terazosin hydrochloride (IDDS-TEH), which included a positive and negative electrode hydrogel prescription. Intact guinea pig skin was used as a model for the skin barrier function, and the current intensity, terazosin hydrochloride (TEH) concentration, pH, competitive salt, and transdermal enhancer properties were studied. The blood drug concentration was determined in Sprague-Dawley (SD) rats using HPLC, and the antihypertensive effects of IDDS-TEH were evaluated in spontaneously hypertensive rats (SHRs). The results showed that the steady-state penetration rate of TEH increased (from 80.36 µg·cm-2·h-1 to 304.93 µg·cm-2·h-1), followed by an increase in the current intensity (from 0.10 mA·cm-2 to 0.49 mA·cm-2). The pH values also had a significant influence on percutaneous penetration. The blood concentration of IDDS-TEH was significantly higher (p < .05) than with passive diffusion, which could not be detected. The main pharmacokinetic parameters of the high current group (0.17 mA·cm-2) and the low current group (0.09 mA·cm-2) were AUC0-t: 5873.0 ng·mL-1·h and 2493.7 ng·mL-1·h, respectively. Meanwhile, the pharmacodynamic results showed that IDDS-TEH significantly decreased the blood pressure of SHRs compared with the TEH hydrogel without loading current. Therefore, TEH could be successfully delivered by the transdermal iontophoresis system in vitro and in vivo, and further clinical studies should be explored to develop a therapeutically useful protocol.
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Antagonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , Sistemas de Liberação de Medicamentos , Hipertensão/tratamento farmacológico , Prazosina/análogos & derivados , Administração Cutânea , Antagonistas de Receptores Adrenérgicos alfa 1/farmacocinética , Antagonistas de Receptores Adrenérgicos alfa 1/farmacologia , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/farmacocinética , Anti-Hipertensivos/farmacologia , Área Sob a Curva , Pressão Sanguínea/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Feminino , Cobaias , Iontoforese , Masculino , Prazosina/administração & dosagem , Prazosina/farmacocinética , Prazosina/farmacologia , Ratos , Ratos Endogâmicos SHR , Ratos Sprague-Dawley , Absorção CutâneaRESUMO
A simple, fast and sensitive LC-MS/MS method was developed to quantify terazosin in human plasma. The mobile phase consisted of acetonitrile-0.1% (v/v) formic acid (70:30, v/v). Prazosin was used as internal standard (IS). As deproteinization agent, acetonitrile produced a clean sample. A higher response intensity with more symmetrical peak was obtained using Agilent Poroshell 120 EC-C18 - Fast LC column (100 × 2.1mmID, 2.7 µm) compared with Kinetex XB-C18 (100 × 2.1 mm, 2.6 µm) column. The response of terazosin and IS were approximately two times in citrate phosphate dextrose (CPD) plasma compared with dipotassium ethylenediaminetetraacetic acid (K2EDTA) plasma. Plasma calibration curve was linear from 1.0 to 100.0 ng/mL, with coefficient of determination r2 ≥ 0.99. The within-run and between-run precision values (CV, %) were <5.2% and <7.8%, while accuracy values were 102.8-112.7% and 103.4-112.2%. The extended run accuracy was 98.6-102.8% and precision (CV, %) 4.3-10.4%. The recovery of analyte was >98% and IS >94%. Terazosin in plasma kept at benchtop was stable for 24 h, in autosampler tray for 48 h, in instrumentation room for 48 h, for 7 freeze-thaw cycles and in freezer for 140 days. Terazosin and IS stock standard solutions were stable for 140 days at room temperature and in the chiller. The high throughput method was successfully utilized to measure 935 samples in a bioequivalence study of terazosin.
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Cromatografia Líquida de Alta Pressão/métodos , Prazosina/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Administração Oral , Adolescente , Adulto , Estudos Cross-Over , Ensaios de Triagem em Larga Escala , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Prazosina/administração & dosagem , Prazosina/sangue , Prazosina/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Equivalência Terapêutica , Adulto JovemRESUMO
WHAT IS KNOWN AND OBJECTIVE: To describe the pharmacological management of post-traumatic stress disorder (PTSD) by psychiatrists, with a focus on their use of clinical guidelines and the role of prazosin for nightmares. METHODS: An online survey of Australian and New Zealand psychiatrists was conducted. Aspects included respondent demographics, familiarity and usage of guidelines for PTSD, and opinions on the safety and efficacy of prazosin for PTSD-associated nightmares. RESULTS AND DISCUSSION: A total of 157 responses were recorded, 106 of which were complete. The most frequently used guideline for PTSD management was over 10 years old and used by only 48% of respondents. Peer-reviewed scientific journals were the most common additional source used by psychiatrists to inform their practice. For the targeted treatment of nightmares, 35 different medications had been trialled by respondents. Prazosin had been prescribed by 86% of psychiatrists for PTSD-associated nightmares, with only 2% reporting it to be ineffective in reducing nightmare frequency and/or intensity. Psychiatrists who were familiar with prazosin-mentioning guidelines (P < .05) and those who more frequently treat patients with PTSD (P < .01) were most likely to have prescribed prazosin. WHAT IS NEW AND CONCLUSION: Psychiatrists generally do not rely on guidelines to inform the treatment of PTSD. Off-label prescription of prazosin for PTSD-associated nightmares occurs frequently, with positive perceived outcomes, despite conflicting published evidence and a lack of local guideline recommendations for its use.
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Sonhos/psicologia , Prazosina/uso terapêutico , Psiquiatria , Transtornos de Estresse Pós-Traumáticos/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália , Estudos Transversais , Feminino , Fidelidade a Diretrizes , Humanos , Masculino , Pessoa de Meia-Idade , Nova Zelândia , Guias de Prática Clínica como Assunto , Prazosina/administração & dosagem , Transtornos de Estresse Pós-Traumáticos/complicações , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Inquéritos e QuestionáriosRESUMO
Black individuals exhibit increased blood pressure (BP) responses to sympathetic stimulation that are associated with an increased risk of hypertension (HTN). We tested the hypothesis that α1 -adrenergic blockade inhibits the increased BP response during and after 45-min stress in young normotensive Black adults, which may be mediated, in part, by dampened vasoconstriction and decreased renal sodium retention. Utilizing a double-masked randomized, crossover study design, 51 normotensive Black adults (31 ± 8 yr) were treated with either a placebo or 1 mg/day of prazosin for 1 week. On the final day of each treatment, hemodynamic measures and urinary sodium excretion (UNaV) were collected before (Rest), during (Stress) and after (Recovery) 45 min of mental stress induced via a competitive video game task. During the Stress period, diastolic BP and total peripheral resistance (TPR) were significantly lower with prazosin compared to placebo (p < .05 for both). Similarly, we observed lower systolic BP, diastolic BP, and TPR during the Recovery period with prazosin versus placebo (p < .05 for both). There was no effect of prazosin on stress-associated UNaV. The change in systolic BP from Rest to Recovery was positively associated with the change in TPR with both treatments (p < .05 for both). In summary, prazosin treatment dampened BP reactivity to 45-min mental stress and lowered post-stress BP over the recovery period, which was linked to reduce TPR in young normotensive Black adults. These results suggest that α1 -adrenergic receptor activity may contribute to BP responses and delayed BP recovery to prolonged mental stress through increased vasoconstriction in Black adults.
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Antagonistas de Receptores Adrenérgicos alfa 1/farmacologia , Prazosina/farmacologia , Estresse Psicológico/metabolismo , Antagonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , Adulto , População Negra , Pressão Sanguínea/efeitos dos fármacos , Feminino , Humanos , Masculino , Prazosina/administração & dosagem , Reflexo/efeitos dos fármacos , Sódio/urina , Estresse Psicológico/etnologia , Estresse Psicológico/fisiopatologiaRESUMO
The emission of 50 kHz frequency-modulated ultrasonic vocalizations (FM USVs) in rats has been associated with positive affective states, while a decrease in FM USVs has been associated with anxiety-like states. We tested the hypothesis in male Sprague-Dawley rats that FM USVs would complement measures of aversive memories (decrease in FM USVs) in a conditioned fear task in which we examined extinction or reconsolidation disruption. In Experiment 1, rats were fear conditioned using low-level footshock followed by extinction while monitoring freezing and FM USVs. In Experiment 2, rats were fear conditioned, the alpha-1 antagonist prazosin was used to disrupt reconsolidation of memory, and freezing and FM USVs were measured. Rats fear conditioned with low-level shock showed minimal freezing that rapidly extinguished, despite a persistent decrease in FM USVs throughout extinction. Prazosin reduced freezing in a memory reactivation-dependent manner as expected, but the reduction in FM USVs after fear conditioning remained decreased, suggesting that an affective component of memory was not impacted by prazosin. These findings indicate that FM USVs may be used as an index of fear- or anxiety-like memory, and their measurement could benefit pre-clinical animal models for assessing reduction of aversive memories.
Assuntos
Medo , Memória , Vocalização Animal , Antagonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Condicionamento Clássico/efeitos dos fármacos , Eletrochoque , Extinção Psicológica/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Consolidação da Memória/efeitos dos fármacos , Prazosina/administração & dosagem , Ratos Sprague-Dawley , UltrassomRESUMO
Pheochromocytomas are uncommon tumours that originate in chromaffin cells. They are a representation of 0.1%-1% of all cases of secondary hypertension. Most pheochromocytomas are unilateral and benign, featuring catecholamine production, as well as the production of other neuropeptides. Pheochromocytomas are mostly located in the adrenal gland; the frequency of occurrence is highest between 30 and 50 years of age; however, up to 25% of cases may be linked to multiple endocrine neoplasia type 2, Von-Hippel-Landau disease and type 1 neurofibromatosis in the young.We present a case of ruptured left adrenal pheochromocytoma with an atypical presentation. A 30-year-old male patient presented with severe left flank pain and hypertension. The CT scan of the abdomen showed bleeding from the left adrenal mass, where resuscitation and angioembolisation were done. Embolisation of the inferior and superior arteries was done, but the middle failed. The patient experienced a significant drop in haemoglobin and a haemorrhagic shock post angioembolisation, which called for emergency laparotomy. The patient is currently doing well with an uneventful postoperative course.
Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico , Extravasamento de Materiais Terapêuticos e Diagnósticos/etiologia , Hipertensão/etiologia , Feocromocitoma/diagnóstico , Cólica Renal/etiologia , Ruptura Espontânea/diagnóstico , Neoplasias das Glândulas Suprarrenais/complicações , Neoplasias das Glândulas Suprarrenais/cirurgia , Glândulas Suprarrenais/diagnóstico por imagem , Glândulas Suprarrenais/patologia , Glândulas Suprarrenais/cirurgia , Adulto , Angiografia por Tomografia Computadorizada , Diagnóstico Diferencial , Embolização Terapêutica , Humanos , Hipertensão/tratamento farmacológico , Masculino , Fentolamina/administração & dosagem , Feocromocitoma/complicações , Feocromocitoma/cirurgia , Prazosina/administração & dosagem , Ruptura Espontânea/etiologia , Ruptura Espontânea/terapia , Resultado do TratamentoRESUMO
Purpose: In guinea pigs, choroidal thickness (ChT) and choroidal blood perfusion (ChBP) simultaneously decrease in experimental myopia, and both increase during recovery. However, the causal relationship between ChBP and myopia requires further investigation. In this study, we examined the changes of ChBP with three different antimyopia treatments. We also actively increased ChBP to examine the direct effect on myopia development in guinea pigs. Methods: Experiment 1: Guinea pigs wore occluders on the right eye for two weeks to induce form-deprivation myopia (FDM). Simultaneously they received daily antimyopia treatments: peribulbar injections of atropine or apomorphine or exposure to intense light. Experiment 2: The vasodilator prazosin was injected daily into the form-deprivation eyes to increase ChBP during the two-week induction of FDM. Other FDM animals received appropriate control treatments. Changes in refraction, axial length, ChBP, ChT, and hypoxia-labeled pimonidazole adducts in the sclera were measured. Results: The antimyopia treatments atropine, apomorphine, and intense light all significantly inhibited myopia development and the decrease in ChBP. The treatments also reduced scleral hypoxia, as indicated by the decrease in hypoxic signals. Furthermore, actively increasing ChBP with prazosin inhibited the progression of myopia, as well as the increase in axial length and scleral hypoxia. Conclusions: Our data strongly indicate that increased ChBP attenuates scleral hypoxia, and thereby inhibits the development of myopia. Thus ChBP may be a promising target for myopia retardation. As such, it can serve as an immediate predictor of myopia development as well as a long-term marker of it.
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Corioide/irrigação sanguínea , Modelos Animais de Doenças , Miopia/prevenção & controle , Antagonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , Animais , Atropina/administração & dosagem , Biometria , Cobaias , Luz , Antagonistas Muscarínicos/administração & dosagem , Miopia/fisiopatologia , Prazosina/administração & dosagem , Refração Ocular , Fluxo Sanguíneo Regional/fisiologia , Esclera/irrigação sanguínea , Privação Sensorial , Tomografia de Coerência ÓpticaRESUMO
Noncompetitive N-methyl-D-aspartate/glutamate receptor (NMDAR) antagonists contribute to the pathophysiology of schizophrenia and mood disorders but improve monoaminergic antidepressant-resistant mood disorder and suicidal ideation. The mechanisms of the double-edged sword clinical action of NMDAR antagonists remained to be clarified. The present study determined the interaction between the NMDAR antagonist (MK801), α1 adrenoceptor antagonist (prazosin), and α2A adrenoceptor agonist (guanfacine) on mesocortical and mesothalamic catecholaminergic transmission, and thalamocortical glutamatergic transmission using multiprobe microdialysis. The inhibition of NMDAR in the locus coeruleus (LC) by local MK801 administration enhanced both the mesocortical noradrenergic and catecholaminergic coreleasing (norepinephrine and dopamine) transmissions. The mesothalamic noradrenergic transmission was also enhanced by local MK801 administration in the LC. These mesocortical and mesothalamic transmissions were activated by intra-LC disinhibition of transmission of γ-aminobutyric acid (GABA) via NMDAR inhibition. Contrastingly, activated mesothalamic noradrenergic transmission by MK801 enhanced intrathalamic GABAergic inhibition via the α1 adrenoceptor, resulting in the suppression of thalamocortical glutamatergic transmission. The thalamocortical glutamatergic terminal stimulated the presynaptically mesocortical catecholaminergic coreleasing terminal in the superficial cortical layers, but did not have contact with the mesocortical selective noradrenergic terminal (which projected terminals to deeper cortical layers). Furthermore, the α2A adrenoceptor suppressed the mesocortical and mesothalamic noradrenergic transmissions somatodendritically in the LC and presynaptically/somatodendritically in the reticular thalamic nucleus (RTN). These discrepancies between the noradrenergic and catecholaminergic transmissions in the mesocortical and mesothalamic pathways probably constitute the double-edged sword clinical action of noncompetitive NMDAR antagonists.
Assuntos
Maleato de Dizocilpina/administração & dosagem , Guanfacina/administração & dosagem , Locus Cerúleo/metabolismo , Prazosina/administração & dosagem , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Córtex Cerebral/metabolismo , Maleato de Dizocilpina/farmacologia , Dopamina/metabolismo , Guanfacina/farmacologia , Hipotálamo/metabolismo , Locus Cerúleo/efeitos dos fármacos , Masculino , Microdiálise/instrumentação , Norepinefrina/metabolismo , Prazosina/farmacologia , Ratos , Transmissão Sináptica/efeitos dos fármacosRESUMO
BACKGROUND: Binge-eating disorder is a pervasive addiction-like disorder that is defined by excessive and uncontrollable consumption of food within brief periods of time. The aim of the current study was to examine the role of the brain noradrenergic system in binge-like eating through the use of the alpha-1 adrenergic receptor antagonist prazosin. METHODS: For this purpose, we employed a limited access model whereby male Wistar rats were allowed to nosepoke for either chow (Chow rats) or a sugary, highly palatable food (Palatable rats) for 1 h/day. The effects of prazosin (0, 0.5, 1 and 2 mg/kg, i.p.) were tested in a fixed ratio 1 (FR1) and progressive ratio (PR) schedule of reinforcement. RESULTS: The results show that prazosin preferentially reduced the responses for palatable food in a FR1 reinforcement schedule; when tested in a PR schedule of reinforcement, prazosin increased breakpoint in both Chow and Palatable rats, but more potently and more efficaciously in the latter. Our results suggest that prazosin treatment preferentially increased the motivational properties of the palatable diet. CONCLUSIONS: The current findings provide the characterization of the effects of prazosin on binge-like eating and offer support to the existing literature showing the important role of the noradrenergic system in addiction-like behavior.
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Antagonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , Transtornos da Alimentação e da Ingestão de Alimentos/tratamento farmacológico , Dependência de Alimentos/tratamento farmacológico , Prazosina/administração & dosagem , Animais , Modelos Animais de Doenças , Transtornos da Alimentação e da Ingestão de Alimentos/etiologia , Dependência de Alimentos/etiologia , Masculino , Norepinefrina/metabolismo , Norepinefrina/fisiologia , Ratos Wistar , Resultado do TratamentoRESUMO
Brain interstitial fluid drainage and extracellular space are closely related to waste clearance from the brain. Different anesthetics may cause different changes of brain interstitial fluid drainage and extracellular space but these still remain unknown. Herein, effects of the inhalational isoflurane, intravenous sedative dexmedetomidine and pentobarbital sodium on deep brain matters' interstitial fluid drainage and extracellular space and underlying mechanisms were investigated. When compared to intravenous anesthetic dexmedetomidine or pentobarbital sodium, inhalational isoflurane induced a restricted diffusion of extracellular space, a decreased extracellular space volume fraction, and an increased norepinephrine level in the caudate nucleus or thalamus with the slowdown of brain interstitial fluid drainage. A local administration of norepinephrine receptor antagonists, propranolol, atipamezole and prazosin into extracellular space increased diffusion of extracellular space and interstitial fluid drainage whilst norepinephrine decreased diffusion of extracellular space and interstitial fluid drainage. These findings suggested that restricted diffusion in brain extracellular space can cause slowdown of interstitial fluid drainage, which may contribute to the neurotoxicity following the waste accumulation in extracellular space under inhaled anesthesia per se.
Assuntos
Anestésicos Inalatórios/administração & dosagem , Dexmedetomidina/administração & dosagem , Líquido Extracelular/efeitos dos fármacos , Espaço Extracelular/efeitos dos fármacos , Hipnóticos e Sedativos/administração & dosagem , Isoflurano/administração & dosagem , Pentobarbital/administração & dosagem , Administração por Inalação , Administração Intravenosa , Animais , Transporte Biológico , Encéfalo , Núcleo Caudado/metabolismo , Drenagem , Humanos , Imidazóis/administração & dosagem , Masculino , Norepinefrina/metabolismo , Prazosina/administração & dosagem , Propranolol/administração & dosagem , Ratos Sprague-Dawley , Tálamo/metabolismoRESUMO
BACKGROUND: Higher levels of anxiety, negative affect, and impaired emotion regulation are associated with alcohol use disorder (AUD) and contribute to relapse and worse treatment outcomes. Prazosin, while typically used to treat post-traumatic stress disorder (PTSD) and other anxiety disorders, has shown promise for treating AUD. In order to better understand these underlying neural processes in individuals with AUD, our aims in this study were to measure brain activation during an anticipatory anxiety task before treatment to determine whether observed patterns supported previous work. We then aimed to measure the effects of prazosin on patients with AUD and explore whether greater baseline anticipatory anxiety (as measured by subjective and neural measures) predicts better treatment outcomes. METHODS: Thirty-four individuals seeking treatment for AUD participated in a six-week placebo-controlled study of prazosin and underwent an anticipatory anxiety task during fMRI scans at baseline and three weeks. Alcohol use over six weeks was measured. RESULTS: Greater levels of subjective anxiety and deactivation in posterior cingulate cortex (PCC) and ventromedial prefrontal cortex (vmPFC) were observed during high-threat stimuli compared to low-threat stimuli. Compared to placebo, prazosin reduced subjective anxiety to high-threat stimuli but there were no observed significant effects of prazosin on brain activation during the task. However, AUD patients with greater vmPFC deactivation during high threat relative to low threat and patients with low baseline anticipatory anxiety during the task had worse clinical outcomes on prazosin. CONCLUSIONS: Deactivation in PCC and vmPFC to high-threat stimuli replicated previous work and shows promise for further study as a marker for AUD. Although prazosin did not affect brain activation in the regions of interest during the anticipatory anxiety task, subjective levels of anxiety and brain activation in vmPFC predicted treatment outcomes in individuals with AUD undergoing treatment with prazosin, highlighting individuals more likely to benefit from prazosin than others.
Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1/farmacologia , Alcoolismo/tratamento farmacológico , Alcoolismo/fisiopatologia , Antecipação Psicológica/fisiologia , Ansiedade/fisiopatologia , Giro do Cíngulo/fisiopatologia , Avaliação de Resultados em Cuidados de Saúde , Prazosina/farmacologia , Córtex Pré-Frontal/fisiopatologia , Adolescente , Antagonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , Adulto , Alcoolismo/diagnóstico por imagem , Antecipação Psicológica/efeitos dos fármacos , Ansiedade/diagnóstico por imagem , Ansiedade/tratamento farmacológico , Feminino , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/efeitos dos fármacos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prazosina/administração & dosagem , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/efeitos dos fármacos , Adulto JovemRESUMO
PURPOSE: We aimed to investigate the comparative efficacy of terazosin and baclofen in young men with chronic orchialgia using National Institutes of Health Chronic Prostatitis Symptom Index measurement. PATIENTS AND METHODS: Of 499 young men with chronic orchialgia, 255 received a daily 2 mg terazosin at bedtime and 244 received 10 mg baclofen during a period of 3 months. A daily 10-min hot-tub hip-bath rest was administered for all patients. Moreover, all patients with grade 3 and 18 patients with grade 2 varicocele underwent varicocelectomy. The National Institutes of Health Chronic Prostatitis Symptom Index score was assessed at baseline and 3 months later. RESULTS: Both terazosin and baclofen groups experienced a significant reduction in mean National Institutes of Health Chronic Prostatitis Symptom Index score (24.78 and 24.81 at baseline to 19.68 and 19.60 after the treatment for terazosin and baclofen groups, respectively). However, there was no significant difference between the groups with regard to post-treatment National Institutes of Health Chronic Prostatitis Symptom Index score after adjustment for the pre-treatment score (p = 0.987). A total of 85 patients (33.4%) in terazosin group and 74 patients (30.3%) in baclofen group underwent varicocelectomy. Addition of the varicocelectomy to the treatment as a multimodal approach had no further improvement in the National Institutes of Health Chronic Prostatitis Symptom Index score. CONCLUSION: Although a significant reduction was observed in mean National Institutes of Health Chronic Prostatitis Symptom Index score for both terazosin and baclofen groups, there was no significant difference between the treatments. Moreover, addition of varicocelectomy to terazosin or baclofen could not significantly decrease National Institutes of Health Chronic Prostatitis Symptom Index score; thus, varicocelectomy may not be appropriate for men who have some success with medical management. Further randomized studies are warranted.
Assuntos
Baclofeno/administração & dosagem , Dor Crônica/tratamento farmacológico , Prazosina/análogos & derivados , Testículo , Adolescente , Adulto , Estudos de Coortes , Humanos , Masculino , Prazosina/administração & dosagem , Resultado do Tratamento , Adulto JovemRESUMO
Management of urinary retention after spinal cord injury in dogs is often needed and can include use of medications to relax the urethral sphincter. This was a retrospective study evaluating two such medications, prazosin and diazepam, and whether dogs treated with these medications had different lengths of hospitalization, urinary continence levels, or development of bacteriuria compared to dogs not receiving these medications after thoracolumbar hemilaminectomy for intervertebral disc herniation (IVDH). Electronic medical records were searched for dogs that underwent CT or MRI followed by a hemilaminectomy between the 3rd thoracic and 3rd lumbar vertebra for treatment of IVDH. Dogs were grouped based on whether or not they received a medication to aid in urethral sphincter relaxation (either prazosin, diazepam, or both medications). The total length of hospitalization, urinary continence at the time of discharge, and presence of bacteriuria were recorded from the medical file. Medical records from 71 dogs were included in the analysis. There were no significant associations between administration of prazosin and/or diazepam and length of hospitalization or urinary continence scores at the time of discharge from the hospital (P > 0.05).
Assuntos
Adjuvantes Anestésicos/uso terapêutico , Diazepam/uso terapêutico , Doenças do Cão/tratamento farmacológico , Deslocamento do Disco Intervertebral/veterinária , Prazosina/uso terapêutico , Traumatismos da Medula Espinal/veterinária , Retenção Urinária/veterinária , Adjuvantes Anestésicos/administração & dosagem , Animais , Diazepam/administração & dosagem , Cães , Feminino , Deslocamento do Disco Intervertebral/cirurgia , Laminectomia/veterinária , Vértebras Lombares , Masculino , Complicações Pós-Operatórias/tratamento farmacológico , Prazosina/administração & dosagem , Registros/veterinária , Estudos Retrospectivos , Traumatismos da Medula Espinal/cirurgia , Vértebras Torácicas , Resultado do Tratamento , Retenção Urinária/tratamento farmacológicoAssuntos
Sistemas de Liberação de Medicamentos/tendências , Glicólise/fisiologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Antagonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , Animais , Sistemas de Liberação de Medicamentos/métodos , Glicólise/efeitos dos fármacos , Humanos , Prazosina/administração & dosagem , Prazosina/análogos & derivadosRESUMO
Bone provides supportive microenvironments for hematopoietic stem cells (HSCs) and mesenchymal stem cells (MSCs) and is a frequent site of metastasis. While incidences of bone metastases increase with age, the properties of the bone marrow microenvironment that regulate dormancy and reactivation of disseminated tumor cells (DTCs) remain poorly understood. Here, we elucidate the age-associated changes in the bone secretome that trigger proliferation of HSCs, MSCs, and DTCs in the aging bone marrow microenvironment. Remarkably, a bone-specific mechanism involving expansion of pericytes and induction of quiescence-promoting secretome rendered this proliferative microenvironment resistant to radiation and chemotherapy. This bone-specific expansion of pericytes was triggered by an increase in PDGF signaling via remodeling of specialized type H blood vessels in response to therapy. The decline in bone marrow pericytes upon aging provides an explanation for loss of quiescence and expansion of cancer cells in the aged bone marrow microenvironment. Manipulation of blood flow - specifically, reduced blood flow - inhibited pericyte expansion, regulated endothelial PDGF-B expression, and rendered bone metastatic cancer cells susceptible to radiation and chemotherapy. Thus, our study provides a framework to recognize bone marrow vascular niches in age-associated increases in metastasis and to target angiocrine signals in therapeutic strategies to manage bone metastasis.