Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
1.
Curr Pain Headache Rep ; 26(9): 677-681, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35816220

RESUMO

PURPOSE OF REVIEW: This article reviews PTPS demographics, diagnosis, pathophysiology, surgical and anesthetic techniques, and their role in preventing PTPS along with updated treatment options. RECENT FINDINGS: Post-thoracotomy pain syndrome (PTPS) can be incapacitating. The neuropathic type pain of PTPS is along the incision site and persists at least 2 months postoperatively. There is a wide reported range of prevalence of PTPS. There are several risk factors that have been identified including surgical technique and younger age. Several surgical and anesthetic techniques have been trialed to reduce pain after thoracotomy. Multimodal pain control is the suggested long-term treatment plan for patients with PTPS. There are several factors that can be modified to reduce pain and incidence of PTPS during the perioperative period and the use of multimodal analgesia is suggested for the treatment of PTPS.


Assuntos
Analgesia , Neuralgia , Dor no Peito/etiologia , Humanos , Neuralgia/etiologia , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/terapia , Toracotomia/efeitos adversos
3.
Curr Pain Headache Rep ; 26(6): 429-438, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35384587

RESUMO

PURPOSE OF REVIEW: This narrative review aims to summarize advances in the field of small fiber neuropathy made over the last decade, with emphasis on novel research highlighting the distinctive features of SFN. RECENT FINDINGS: While the management of SFNs is ideally aimed at treating the underlying cause, most patients will require pain control via multiple, concurrent therapies. Herein, we highlight the most up-to-date information for diagnosis, medication management, interventional management, and novel therapies on the horizon. Despite the prevalence of small fiber neuropathies, there is no clear consensus on guidelines specific for the treatment of SFN. Despite the lack of specific guidelines for SFN treatment, the most recent general neuropathic pain guidelines are based on Cochrane studies and randomized controlled trials (RCTs) which have individually examined therapies used for the more commonly studied SFNs, such as painful diabetic neuropathy and HIV neuropathy. The recommendations from current guidelines are based on variables such as number needed to treat (NNT), safety, ease of use, and effect on quality of life.


Assuntos
Neuropatias Diabéticas , Neuralgia , Neuropatia de Pequenas Fibras , Neuropatias Diabéticas/diagnóstico , Neuropatias Diabéticas/epidemiologia , Neuropatias Diabéticas/terapia , Humanos , Neuralgia/tratamento farmacológico , Neuralgia/terapia , Neuropatia de Pequenas Fibras/diagnóstico , Neuropatia de Pequenas Fibras/etiologia , Neuropatia de Pequenas Fibras/terapia
4.
Vet Parasitol ; 247: 1-6, 2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29080753

RESUMO

Monogenean parasites are important ectoparasites of fish, and are responsible for severe economic impacts in the aquaculture industry. They are usually treated with chemicals, but the chemicals can have harmful side effects in the fish and may pose threats to human health. Rosemary (Rosmarinus officinalis) is a common medicinal herb, with antimicrobial and antitumor properties. Here, we examined the anthelmintic activity of rosemary extract against the monogenean (Dactylogyrus minutus) in vitro and in vivo using bath treatment and oral administration. The in vitro experiments showed that parasite survival was affected by both rosemary extract concentration and the solvent (water and ethanol). Parasites were dead at 61.8±5.6 and 7.8±1.4min when exposed to 100 and 200g aqueous rosemary extract solution/L of water respectively. It took 166.7±48.2 and 5.4±1.01min to kill the parasites when exposed to 1 and 32g ethanol rosemary extract solution/L of water respectively. Moreover, pure component of rosemary extract obtained commercially used in in vitro experiments showed that 1,8-Cineole was the most toxic component of the main components tested. Parasite intensity and prevalence in fish exposed to 50 and 100g aqueous rosemary solution/L water for 30min were significantly lower than they were in controls (p<0.05). In oral treatment experiments, diets of Cyprinus carpio were supplemented with eight different concentrations of aqueous rosemary extract. The intensity of parasites was significantly less in fish fed for 30days with feed containing 60, 80 and 100ml aqueous extract/100g feed than in control (p<0.05). Together these results indicate that rosemary is a promising candidate for prevention and control of monogenean infection.


Assuntos
Anti-Helmínticos/farmacologia , Carpas/parasitologia , Doenças dos Peixes/tratamento farmacológico , Helmintíase Animal/tratamento farmacológico , Extratos Vegetais/farmacologia , Rosmarinus/química , Animais , Anti-Helmínticos/química , Anti-Helmínticos/isolamento & purificação , Aquicultura , Cicloexanóis/química , Cicloexanóis/isolamento & purificação , Cicloexanóis/farmacologia , Eucaliptol , Doenças dos Peixes/parasitologia , Doenças dos Peixes/prevenção & controle , Helmintíase Animal/parasitologia , Helmintíase Animal/prevenção & controle , Monoterpenos/química , Monoterpenos/isolamento & purificação , Monoterpenos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Plantas Medicinais , Platelmintos/efeitos dos fármacos
5.
Lymphat Res Biol ; 15(4): 343-348, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28956696

RESUMO

BACKGROUND: This aim of this study was to assess and compare arterial and venous circulation in women with axillary lymph node dissection (ALND) and sentinel lymph node biopsy (SLNB) before and after breast cancer surgery. METHODS AND RESULTS: Fifty-two women took part in the study, divided into three groups: those undergoing ALND at levels I, II, and III (ALNDG), with mean age of 56.29 ± 10.85 years old; those undergoing sentinel lymph node biopsy (SLNBG), with mean age of 57.7 ± 7.07 years old; and controls without diagnosis of breast cancer (CG), with mean age of 53.92 ± 8.85 years old. Maximum venous and arterial flow velocities in upper limbs were assessed before and after surgical treatment for breast cancer by means of Doppler ultrasonography (Nicolet Vascular Versalab SE®). Data normality was assessed by using the Shapiro-Wilk's test, with normally distributed variables being analyzed with analysis of variance (ANOVA) and post hoc Tukey's test or t-test. For variables with non-normal distribution, Kruskal-Wallis' test and post hoc Dunn's test were used at p < 0.05. There was significant difference in the maximum blood flow velocities, both venous (ALNDG) and arterial (SLNBG). CONCLUSION: The results suggest that ALND and SLNB can interfere with the upper limp blood circulation.


Assuntos
Neoplasias da Mama/complicações , Excisão de Linfonodo/efeitos adversos , Fluxo Sanguíneo Regional , Biópsia de Linfonodo Sentinela/efeitos adversos , Extremidade Superior/irrigação sanguínea , Extremidade Superior/fisiopatologia , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade
6.
J Fish Dis ; 40(10): 1341-1350, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28111768

RESUMO

In 2013, an outbreak of ulcerative disease associated with ranavirus infection occurred in barcoo grunter, Scortum barcoo (McCulloch & Waite), farms in Thailand. Affected fish exhibited extensive haemorrhage and ulceration on skin and muscle. Microscopically, the widespread haemorrhagic ulceration and necrosis were noted in gill, spleen and kidney with the presence of intracytoplasmic eosinophilic inclusion bodies. When healthy barcoo grunter were experimentally challenged via intraperitoneal and oral modes with homogenized tissue of naturally infected fish, gross and microscopic lesions occurred with a cumulative mortality of 70-90%. Both naturally and experimentally infected fish yielded positive results to the ranavirus-specific PCR. The full-length nucleotide sequences of major capsid protein gene of ranaviral isolates were similar to largemouth bass virus (LMBV) and identical to largemouth bass ulcerative syndrome virus (LBUSV), previously reported in farmed largemouth bass (Micropterus salmoides L.), which also produced lethal ulcerative skin lesions. To the best of our knowledge, this is the first report of a LMBV-like infection associated with skin lesions in barcoo grunter, adding to the known examples of ranavirus infection associated with skin ulceration in fish.


Assuntos
Infecções por Vírus de DNA/veterinária , Surtos de Doenças/veterinária , Doenças dos Peixes/epidemiologia , Perciformes , Ranavirus/fisiologia , Animais , Proteínas do Capsídeo/genética , Infecções por Vírus de DNA/epidemiologia , Infecções por Vírus de DNA/virologia , Doenças dos Peixes/virologia , Filogenia , Ranavirus/genética , Análise de Sequência de Proteína/veterinária , Tailândia
7.
Braz J Phys Ther ; 19(2): 122-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25993626

RESUMO

BACKGROUND: Infrared thermography is recognized as a viable method for evaluation of subjects with myofascial pain. OBJECTIVE: The aim of the present study was to assess the intra- and inter-rater reliability of infrared image analysis of myofascial trigger points in the upper trapezius muscle. METHOD: A reliability study was conducted with 24 volunteers of both genders (23 females) between 18 and 30 years of age (22.12 ± 2.54), all having cervical pain and presence of active myofascial trigger point in the upper trapezius muscle. Two trained examiners performed analysis of point, line, and area of the infrared images at two different periods with a 1-week interval. The intra-class correlation coefficient (ICC(2,1)) was used to assess the intra- and inter-rater reliability. RESULTS: With regard to the intra-rater reliability, ICC values were between 0.591 and 0.993, with temperatures between 0.13 and 1.57 °C for values of standard error of measurement (SEM) and between 0.36 and 4.35 °C for the minimal detectable change (MDC). For the inter-rater reliability, ICC ranged from 0.615 to 0.918, with temperatures between 0.43 and 1.22 °C for the SEM and between 1.19 and 3.38 °C for the MDC. CONCLUSION: The methods of infrared image analyses of myofascial trigger points in the upper trapezius muscle employed in the present study are suitable for clinical and research practices.


Assuntos
Raios Infravermelhos , Síndromes da Dor Miofascial/diagnóstico , Síndromes da Dor Miofascial/fisiopatologia , Músculos Superficiais do Dorso/fisiologia , Termografia/métodos , Pontos-Gatilho/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
8.
Braz. j. phys. ther. (Impr.) ; 19(2): 122-128, 27/04/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-745813

RESUMO

BACKGROUND: Infrared thermography is recognized as a viable method for evaluation of subjects with myofascial pain. OBJECTIVE: The aim of the present study was to assess the intra- and inter-rater reliability of infrared image analysis of myofascial trigger points in the upper trapezius muscle. METHOD: A reliability study was conducted with 24 volunteers of both genders (23 females) between 18 and 30 years of age (22.12±2.54), all having cervical pain and presence of active myofascial trigger point in the upper trapezius muscle. Two trained examiners performed analysis of point, line, and area of the infrared images at two different periods with a 1-week interval. The intra-class correlation coefficient (ICC2,1) was used to assess the intra- and inter-rater reliability. RESULTS: With regard to the intra-rater reliability, ICC values were between 0.591 and 0.993, with temperatures between 0.13 and 1.57 °C for values of standard error of measurement (SEM) and between 0.36 and 4.35 °C for the minimal detectable change (MDC). For the inter-rater reliability, ICC ranged from 0.615 to 0.918, with temperatures between 0.43 and 1.22 °C for the SEM and between 1.19 and 3.38 °C for the MDC. CONCLUSION: The methods of infrared image analyses of myofascial trigger points in the upper trapezius muscle employed in the present study are suitable for clinical and research practices. .


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Adulto Jovem , Termografia/métodos , Pontos-Gatilho/fisiologia , Músculos Superficiais do Dorso/fisiologia , Raios Infravermelhos , Síndromes da Dor Miofascial/diagnóstico , Síndromes da Dor Miofascial/fisiopatologia
9.
Arch Phys Med Rehabil ; 94(12): 2465-2470, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23806609

RESUMO

OBJECTIVE: To assess the influence of diabetic neuropathy (DN) on balance and functional strength in patients with diabetes mellitus type 2 (DM2). DESIGN: Cross-sectional study. SETTING: Diabetes outpatient unit. PARTICIPANTS: Adults (N=62; age range, 40-65y): 32 with DM2 (19 subjects without DN and 13 with DN) and 30 without DM2 (control group). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Upright balance, evaluated in 4 situations (fixed platform, unstable platform, with eyes open, with eyes closed), and functional strength, assessed with a five-times-sit-to-stand test, were analyzed using an electromagnetic system, with a sensor placed over C7 to allow maximum trunk displacements in the anterior-posterior and medial-lateral directions. The Berg Balance Scale and the Timed Up & Go test were also used. RESULTS: Subjects with DM2 had greater anterior-posterior displacement (P<.05) in the unstable platform with eyes closed condition compared with those without DM2, whereas no difference in medial-lateral displacement was observed between these groups. A difference in time was observed in the five-times-sit-to-stand test (P<.05), with subjects in the control group performing the tasks faster than either group of subjects with DM2. Additionally, subjects in the control group showed a higher score in the Berg Balance Scale and performed the Timed Up & Go test in less time compared with subjects in other groups. CONCLUSIONS: Subjects with DM2, with or without DN, showed deficits in postural control and functional strength compared with healthy individuals of the same age group.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Neuropatias Diabéticas/fisiopatologia , Força Muscular/fisiologia , Equilíbrio Postural/fisiologia , Adulto , Idoso , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Movimento/fisiologia
10.
J Comp Pathol ; 147(2-3): 259-66, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22316434

RESUMO

The toxicity of melamine and its analogue in man and animals has been reported widely. The aim of the present study was to examine the pathological effects of feeding melamine and cyanuric acid, separately or in combination, to walking catfish (Clarius batrachus). The catfish developed darkening of the skin as early as 3 days post feeding. Melamine-related crystals were distributed multifocally throughout the liver, kidney, heart, spleen and corpuscle of Stannius of fish fed melamine and cyanuric acid in combination. Oil red O staining and electron microscopy revealed that the melamine-related crystals had structure resembling that of plastic polymer crystals. Elevations in the serum concentrations of alanine transaminase, aspartate transaminase, creatinine and uric acid were related to the crystal-associated granulomatous inflammation in the liver and kidney of affected fish. None of the catfish died during the 2-week experiment. Melamine and cyanuric acid are therefore systemically toxic to fish in addition to causing renal crystal formation and renal damage as seen in man and animals. The finding of extrarenal crystals implies that the metabolism and biotransformation of these toxic compounds should be further investigated in aquatic animals.


Assuntos
Triazinas/administração & dosagem , Ração Animal , Animais , Peixes-Gato , Cristalização , Quimioterapia Combinada , Contaminação de Alimentos , Granuloma/induzido quimicamente , Granuloma/metabolismo , Granuloma/patologia , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Testes de Função Hepática , Transtornos da Pigmentação/induzido quimicamente , Transtornos da Pigmentação/patologia , Pele/efeitos dos fármacos , Pele/patologia , Testes de Toxicidade
11.
Res Vet Sci ; 91(3): e92-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21536310

RESUMO

The use of lactic acid bacteria from human origins as a potential probiotic supplementation in aquaculture feed is now widely accepted. Here, we examined some of the properties and mechanisms of the action of Lactobacillus rhamnosus GG, originating from humans, on growth performance, gut mucosal immunity and humoral and cellular immune response in tilapia (Oreochromis niloticus). The results suggested that supplementation of L. rhamnosus gave an advantage in promoting the intestinal structure and the mucosal immunity of tilapia. Probiotic fish had a greater villous height in all parts of the intestines and, significantly, in the proximal and middle part. The population of intraepithelial lymphocytes was significantly higher in the probiotic group than in the control group in all parts of the intestines. The population of acidophilic granulocyte in the probiotic group was significantly higher at the proximal and distal parts when compared with the control group. The higher serum complement activity as well as the enhanced phagocytosis and killing ability of the head kidney leukocytes in the probiotic supplemented fish corresponded with the higher level of TNF alpha and IL-1 gene expression, suggesting that the induction of IL-1 and TNF alpha cytokines by L. rhamnosus served as an important regulator of gut associated immune systems.


Assuntos
Ciclídeos/imunologia , Intestinos/anatomia & histologia , Intestinos/microbiologia , Lacticaseibacillus rhamnosus/fisiologia , Probióticos , Ração Animal , Animais , Ciclídeos/crescimento & desenvolvimento , Dieta/veterinária , Suplementos Nutricionais , Granulócitos/citologia , Granulócitos/fisiologia , Rim Cefálico/citologia , Mucosa Intestinal/citologia , Intestinos/imunologia , Muramidase , Fagocitose , Streptococcus/imunologia
12.
Arq. bras. med. vet. zootec ; 59(5): 1301-1307, out. 2007. graf, tab
Artigo em Inglês | LILACS | ID: lil-471216

RESUMO

The role of cortisol on the osmoregulation of pejerrey Odontesthes bonariensis at different salinities was investigated in adult fish injected with 0.7mg hydrocortisone per 100g body weight of fish, and transferred to 0, 5 and 20ppt of NaCl. Blood cortisol was 566ng/ml at the beginning of the experiment (0h) but surged to 1250ng/ml within 3h in cortisol-injected fish. Cortisol levels were influenced not only by treatment but also by time, being higher at 3h compared to 24h. Salinity level, time of exposure and their interaction, but not cortisol treatment, significantly affected plasma osmolality and the concentration of ions Cl- and Na+. This study showed that exogenous cortisol does not seem to play a significant role on the regulation of plasma osmolality and concentration of individual ions in pejerrey


Investigou-se a participação do cortisol na osmoregulação de peixe-rei Odontesthes bonariensis, em diferentes salinidades, em peixes adultos injetados com 0,7mg hidrocortisona por 100g de peso corporal, e transferidos para 0, 5 e 20ppt de NaCl. No inicio do experimento (0h), o cortisol encontrado no plasma foi de 566ng/ml, aumentando para 1250ng/ml em 3h em peixes injetados com cortisol. A concentração de cortisol foi influenciada não somente pelo tratamento, mas também pelo tempo, sendo maior 3h após a inoculação, comparada à 24h. A salinidade, o tempo de exposição e a interação desses dois fatores, mas não o tratamento com o cortisol, afetaram significativamente a osmolaridade e a concentração dos íons Cl- e Na+ do plasma. Este estudo mostrou que, o cortisol exógeno não influi significativamente na regulação da osmolaridade e da concentração de íons Na+ e Cl- no plasma em peixe-rei


Assuntos
Aclimatação , Peixes , Hidrocortisona/efeitos adversos , Hidrocortisona , Concentração Osmolar , Salinidade , Equilíbrio Hidroeletrolítico
14.
Am J Physiol ; 271(6 Pt 2): H2306-12, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8997287

RESUMO

Rats with congestive heart failure demonstrate striking intrarenal vasoconstriction that contributes to reduced renal excretory function. The importance of specific angiotensin II receptor subtypes (AT1, AT2) for mediating changes in renal hemodynamics was studied in anesthetized rats 1 mo after myocardial infarction (MI) created by coronary artery ligation. AT1 antagonism with losartan alone decreased mean arterial pressure (MAP), total peripheral resistance (TPR), and renal resistance (RR) in control and MI rats to a similar extent without affecting renal blood flow (RBF) or RBF as a percentage of cardiac output (%RBF/CO). In contrast, AT2 antagonism with PD-123319 alone significantly reduced MAP and RR in MI rats without affecting these parameters in control rats. TPR and %RBF/CO were not changed significantly in either group. In contrast, combined AT1- and AT2-receptor inhibition lowered TPR and RR and increased RBF and %RBF/CO, thus the effects of renin or ACE inhibition were mimicked in MI rats. We conclude that angiotensin II acts at both AT1 and AT2 receptor sites in rats with reduced cardiac mass to modulate renal hemodynamics.


Assuntos
Antagonistas de Receptores de Angiotensina , Infarto do Miocárdio/fisiopatologia , Circulação Renal , Animais , Compostos de Bifenilo/farmacologia , Hemodinâmica , Imidazóis/farmacologia , Losartan , Masculino , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Valores de Referência , Tetrazóis/farmacologia
15.
J Clin Invest ; 96(1): 183-91, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7615788

RESUMO

We tested the hypothesis that endothelin (ET) responsiveness in the renal medulla is modulated by ambient osmolarity. Cultured renal medullary interstitial cells (RMICs) were incubated from 3 to 24 h in isosmolar culture medium (300 mOsm/kg H2O) or media rendered hyperosmolar (600 mOsm/kg H2O) by the addition of urea. Under hyperosmolar conditions, the peak of ET-evoked Ca2+ transient was blunted by 45-58% (P < 0.02) and PGE2 accumulation decreased from 16- to 2-fold above basal values (P < 0.001). To explore whether hyperosmolar conditions blunt intracellular signaling via modulation of receptor number or expression, kinetics of ET binding and Northern blot analysis of ETA receptor mRNA was performed. Under hyperosmolar conditions, ETA receptor density was reduced by 84% versus isosmolar conditions (238 +/- 12 vs. 1450 +/- 184 fmol/mg) (P < 0.01). In contrast to the ligand binding studies, ETA receptor mRNA was increased by 58% (P < 0.05) in cells grown under hyperosmolar versus isosmolar media. These observations indicate that in the hyperosmolar setting, ET-evoked intracellular signaling is blunted in RMICs due to ET receptor downregulation. Since ETA receptor mRNA is increased under hyperosmolar conditions, we conclude that ET receptor downregulation is the consequence of either decreased translation of message, increased degradation of receptor peptide, or increased internalization of specific receptor sites.


Assuntos
Endotelinas/farmacologia , Medula Renal/efeitos dos fármacos , Animais , Sequência de Bases , Cálcio/metabolismo , Células Cultivadas , Dinoprostona/biossíntese , Dados de Sequência Molecular , Concentração Osmolar , Proteína Quinase C/fisiologia , RNA Mensageiro/análise , Ratos , Receptores de Endotelina/análise , Receptores de Endotelina/genética , Receptores de Endotelina/fisiologia
16.
Hypertension ; 23(6 Pt 2): 853-6, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8206617

RESUMO

The aim of this study was to determine whether angiotensin receptor subtypes play a role in angiotensin clearance from plasma. Angiotensin metabolic clearance rate was measured in rats by the constant infusion method. Increasing doses of angiotensin II were infused for 15 minutes, and blood was sampled for angiotensin II. The type 1 angiotensin II receptor antagonist losartan decreased the apparent metabolic clearance rate by > 50% at low-dose infusion, suggesting that type 1 angiotensin II receptors are involved in angiotensin II clearance from plasma. At higher angiotensin infusion rates, the-metabolic clearance rate of angiotensin was unaffected. To dissect the contribution of renin-generated angiotensin, additional experiments were performed in nephrectomized rats. In anephric rats, angiotensin clearance was unaffected by type 1 angiotensin II receptor inhibition. In contrast, the type 2 angiotensin II receptor ligand PD123319 in intact rats caused a > 50% increase in metabolic clearance rate of angiotensin at higher infusion rates (P < .05). In anephric rats, the type 2 angiotensin II receptor ligand alone or combined with type 1 receptor inhibition was without effect on the metabolic clearance rate or the T1/2 for angiotensin disappearance. These data argue against a role for type 1 or 2 angiotensin II receptors as clearance receptors. Increased clearance of angiotensin by type 2 receptor blockade in the presence but not the absence of kidneys suggests an alternative renal mechanism by which selective type 2 ligands may alter angiotensin effects.


Assuntos
Angiotensina II/sangue , Antagonistas de Receptores de Angiotensina , Animais , Compostos de Bifenilo/farmacologia , Imidazóis/farmacologia , Losartan , Masculino , Taxa de Depuração Metabólica/efeitos dos fármacos , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Tetrazóis/farmacologia
17.
J Cardiovasc Pharmacol ; 21(5): 791-6, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-7685451

RESUMO

Renal and systemic hemodynamics were studied in rats 1 month after induction of myocardial infarction by ligation of the left coronary artery. The mean arterial pressure, heart rate, and cardiac index were not different from controls, but there were striking elevations in heart weight (p < 0.001), left ventricular end diastolic pressure (p < 0.002), and renal vascular resistance (p < 0.01). Renal blood flow and the percent of cardiac output perfusing the kidneys were reduced by 18% (p < 0.01) and 14% (p < 0.01), respectively. Acute angiotensin inhibition was studied at a dose of the converting enzyme inhibitor, enalapril, or the renin inhibitor, CP71362, that lowered the mean arterial pressure by 15 mm Hg in normal rats. In normal rats, enalapril and CP71362 were without effect on renal blood flow (RBF), renal vascular resistance (RR), and RBF as a percent of cardiac output. However, in rats with myocardial infarction, enalapril and CP71362 increased the RBF and RBF as a percent of cardiac output and lowered the RR to levels similar to normal controls (p < 0.02). Enalapril and CP71362 were equally effective in reducing the left ventricular end-diastolic pressure and total peripheral resistance in rats with myocardial infarction. These data demonstrate significant intrarenal vasoconstriction following myocardial infarction in the absence of detectable changes in mean arterial pressure or cardiac index. Converting enzyme inhibition or renin inhibition had similar beneficial effects on cardiorenal function, suggesting that both classes of compounds act by a similar mechanism to improve renal hemodynamics in congestive heart failure.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Infarto do Miocárdio/fisiopatologia , Renina/antagonistas & inibidores , Animais , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Circulação Coronária/efeitos dos fármacos , Vasos Coronários/fisiologia , Enalapril/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Masculino , Microesferas , Oligopeptídeos/farmacologia , Ratos , Ratos Sprague-Dawley , Circulação Renal/efeitos dos fármacos
18.
Am J Physiol ; 260(1 Pt 2): F110-8, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1847009

RESUMO

Glomerular endothelin (ET) receptors were studied in normal Sprague-Dawley rats and in rats with ischemic acute renal failure (ARF) induced by a 60-min occlusion of the left renal artery (right kidney intact). In normal rats ET bound to specific glomerular receptor sites [equilibrium affinity constant (Kd), 46.6 +/- 5.8 pM; receptor number (Ro), 1,167 +/- 160 fmol/mg (n = 7)]. ET infusion (90 ng.kg-1.min-1, intra-arterially) raised mean arterial pressure by 32 +/- 4 mmHg, lowered renal blood flow (RBF) by 62% and glomerular filtration rate (GFR) by 49%, and reduced the number of glomerular ET receptor sites by 62%. Reduced ET binding could not be explained by prior occupancy, because acid treatment (which dissociates bound ET from its receptors) did not increase receptor number. If elevated ET levels contributed to decreased RBF and GFR in ARF, glomerular ET receptors would be expected to down-regulate. In rats with ischemic ARF there were no differences in the number or affinity of glomerular ET receptors in the clamped or contralateral kidneys. Additional studies demonstrated that the downregulation response to ET infusion was intact in ARF. The data demonstrate that glomerular ET receptors are unaltered in ischemic ARF and do not support a role for increased glomerular ET in the alterations of renal hemodynamics in this model.


Assuntos
Injúria Renal Aguda/fisiopatologia , Isquemia/fisiopatologia , Glomérulos Renais/ultraestrutura , Receptores de Superfície Celular/fisiologia , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Animais , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Endotelinas/administração & dosagem , Endotelinas/metabolismo , Endotelinas/farmacologia , Hemodinâmica/efeitos dos fármacos , Infusões Intra-Arteriais , Isquemia/metabolismo , Isquemia/patologia , Rim/irrigação sanguínea , Rim/patologia , Rim/fisiopatologia , Glomérulos Renais/patologia , Glomérulos Renais/fisiopatologia , Cinética , Masculino , Ratos , Ratos Endogâmicos , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Receptores de Endotelina
19.
Am J Physiol ; 258(5 Pt 1): E864-70, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-2159236

RESUMO

This investigation was performed to study the potential role of endothelin in the modulation of fetoplacental vascular resistance in the human placenta. Full-term placentas from uncomplicated pregnancies were studied within 30 min of delivery. The umbilical artery and vein to a single placental cotyledon were cannulated and the artery perfused with RPMI media (0.82 ml/min). Endothelin 1 caused a sustained dose-dependent increase in perfusion pressure. Infused endothelin 1 (50 nM) stimulated thromboxane release 2.3-fold compared with basal values. Thromboxane release persisted for 15 min after discontinuation of endothelin. Properties of human placental endothelin 1 receptors were defined in binding studies performed on a crude membrane fraction of placental cotyledons. Binding was saturable, reached steady state by 3 h at 25 degrees C, and was linear with protein concentration. Scatchard analysis of binding data indicated a single class of high-affinity binding sites with a Kd of 36.1 +/- 9.7 pM and a density of 185.4 +/- 9.6 fmol/mg protein (n = 5). The potency order for competitive inhibition of the binding of 125I-labeled endothelin 1 was endothelin 1 greater than endothelin 2 = endothelin 3 = sarafotoxin S6b greater than big endothelin (human) = big endothelin (porcine). Phenylephrine, bradykinin, norepinephrine, atrial natriuretic factor, diltiazem, U46619, and angiotensin II did not displace 125I-endothelin 1 from its receptors. These experiments demonstrate that endothelin 1 is a potent pressor substance in the human fetoplacental cotyledon. Pressor effects of endothelin may be mediated by a combination of direct effects and stimulation of vasoconstrictor prostanoids.


Assuntos
Peptídeos/farmacologia , Placenta/fisiologia , Receptores de Superfície Celular/fisiologia , Tromboxano B2/metabolismo , Ligação Competitiva , Membrana Celular/metabolismo , Endotelinas , Endotélio Vascular/fisiologia , Feminino , Humanos , Técnicas In Vitro , Cinética , Peptídeos/metabolismo , Perfusão , Placenta/irrigação sanguínea , Gravidez , Ensaio Radioligante , Receptores de Superfície Celular/efeitos dos fármacos , Receptores de Endotelina , Resistência Vascular
20.
Am J Physiol ; 256(6 Pt 2): F1111-6, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2525345

RESUMO

The aim of this study was to identify and characterize thromboxane (Tx) receptor sites in renal glomeruli. Binding studies were performed on freshly isolated glomeruli using the stable TxA2 receptor antagonist, [3H]SQ 29548. Specific binding was saturable, reversible, and varied with glomerular protein. Scatchard plots revealed a single class of high-affinity receptor sites (Kd = 14.3 +/- 2.4 nM, Bmax = 361 +/- 22 fmol/mg; n = 5). Specific binding was inhibited by Tx agonists (U-46619 and U-44069) and antagonist (SQ 29548) and was highly specific for Tx, since prostaglandin (PG)E2 and PGF2 alpha were 1,000-fold less potent in inhibiting binding. In vivo, U-46619 (1.75 micrograms.kg-1.min-1) was without effect on mean arterial pressure, but reduced renal blood flow by 71% (P less than 0.01) and glomerular filtration rate by 67% (P less than 0.01) and increased filtration fraction by 24% (P less than 0.05). SQ 29548 (10 micrograms.kg-1.min-1) completely blocked the renal effects of U-46619. These studies demonstrate the presence of specific receptor sites for Tx on renal glomeruli that are linked to modulation of renal hemodynamics.


Assuntos
Taxa de Filtração Glomerular/efeitos dos fármacos , Hidrazinas/farmacologia , Glomérulos Renais/metabolismo , Endoperóxidos Sintéticos de Prostaglandinas/farmacologia , Receptores de Prostaglandina/metabolismo , Circulação Renal/efeitos dos fármacos , Tromboxano B2/metabolismo , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico , Animais , Ligação Competitiva , Compostos Bicíclicos Heterocíclicos com Pontes , Ácidos Graxos Insaturados , Hidrazinas/metabolismo , Cinética , Masculino , Ratos , Ratos Endogâmicos , Receptores de Tromboxanos , Tromboxano B2/antagonistas & inibidores
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA