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1.
Int J Mol Sci ; 24(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37446125

RESUMO

The enhancement of the endocannabinoid tone might have a beneficial influence on hypertension. Polypharmacology proposes multi-target-directed ligands (MTDLs) as potential therapeutic agents for the treatment of complex diseases. In the present paper, we studied JZL195, a dual inhibitor of the two major endocannabinoid-degrading enzymes, fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL), in spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto rats (WKY). Hemodynamic parameters were assessed in conscious animals via radiotelemetry and tail-cuff methods and then evaluated by the area under the curve (AUC). Single administration of JZL195 induced dose-dependent weak hypotensive and bradycardic responses in SHR but not in WKY. Similarly, its chronic application revealed only a slight hypotensive potential which, however, effectively prevented the progression of hypertension and did not undergo tolerance. In addition, multiple JZL195 administrations slightly decreased heart rate only in WKY and prevented the gradual weight gain in both groups. JZL195 did not affect organ weights, blood glucose level, rectal temperature and plasma oxidative stress markers. In conclusion, chronic dual FAAH/MAGL inhibition prevents the progression of hypertension in SHR without affecting some basal functions of the body. In addition, our study clearly proves the suitability of AUC for the evaluation of weak blood pressure changes.


Assuntos
Hipertensão , Monoacilglicerol Lipases , Ratos , Animais , Piperidinas/farmacologia , Ratos Endogâmicos SHR , Monoglicerídeos , Endocanabinoides , Amidoidrolases , Hipertensão/tratamento farmacológico
2.
Pharmacol Rep ; 75(4): 755-770, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37278927

RESUMO

Polypharmacology is an emerging strategy of design, synthesis, and clinical implementation of pharmaceutical agents that act on multiple targets simultaneously. It should not be mixed up with polytherapy, which is based on the use of multiple selective drugs and is considered a cornerstone of current clinical practice. However, this 'classic' approach, when facing urgent medical challenges, such as multifactorial diseases, increasing resistance to pharmacotherapy, and multimorbidity, seems to be insufficient. The 'novel' polypharmacology concept leads to a more predictable pharmacokinetic profile of multi-target-directed ligands (MTDLs), giving a chance to avoid drug-drug interactions and improve patient compliance due to the simplification of dosing regimens. Plenty of recently marketed drugs interact with multiple biological targets or disease pathways. Many offer a significant additional benefit compared to the standard treatment regimens. In this paper, we will briefly outline the genesis of polypharmacology and its differences to polytherapy. We will also present leading concepts for obtaining MTDLs. Subsequently, we will describe some successfully marketed drugs, the mechanisms of action of which are based on the interaction with multiple targets. To get an idea, of whether MTDLs are indeed important in contemporary pharmacology, we also carefully analyzed drugs approved in 2022 in Germany: 10 out of them were found multi-targeting, including 7 antitumor agents, 1 antidepressant, 1 hypnotic, and 1 drug indicated for eye disease.


Assuntos
Polifarmacologia , Humanos
3.
Front Pharmacol ; 13: 965613, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36120288

RESUMO

Pulmonary hypertension (PH) is a disease leading to increased pressure in the pulmonary artery and right heart failure. The adenosine monophosphate-activated protein kinase (AMPK) activator, metformin, has a protective effect against PH. CB1 receptor blockade reduces the number of pathological alterations in experimental lung fibrosis. The current study evaluates the effect of the peripheral cannabinoid CB1 receptor antagonist JD5037 in mono- and polytherapy with metformin in rat monocrotaline-induced mild PH. Animals received metformin (100 mg/kg), JD5037 (3 mg/kg), or a combination of both once daily for 21 days. Monocrotaline (60 mg/kg) increased right ventricular (RV) systolic pressure (RVSP), led to RV and lung hypertrophy and remodeling, and decreased oxygen saturation. Metformin partially restored the monocrotaline-induced effects, i.e., decreased RVSP, increased oxygen saturation, and counteracted cardiac fibrotic, hypertrophic, and inflammatory changes. JD5037 modified parameters related to inflammation and/or fibrosis. Only polytherapy with metformin and JD5037 improved Fulton's index and coronary artery hypertrophy and tended to be more effective than monotherapy against alterations in RVSP, oxygen saturation and coronary artery tunica media vacuolization. In conclusion, monotherapy with JD5037 does not markedly influence the PH-related changes. However, polytherapy with metformin tends to be more efficient than any of these compounds alone.

4.
Cells ; 11(7)2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35406706

RESUMO

The use of cannabis preparations has steadily increased. Although cannabis was traditionally assumed to only have mild vegetative side effects, it has become evident in recent years that severe cardiovascular complications can occur. Cannabis use has recently even been added to the risk factors for myocardial infarction. This review is dedicated to pathogenetic factors contributing to cannabis-related myocardial infarction. Tachycardia is highly important in this respect, and we provide evidence that activation of CB1 receptors in brain regions important for cardiovascular regulation and of presynaptic CB1 receptors on sympathetic and/or parasympathetic nerve fibers are involved. The prototypical factors for myocardial infarction, i.e., thrombus formation and coronary constriction, have also been considered, but there is little evidence that they play a decisive role. On the other hand, an increase in the formation of carboxyhemoglobin, impaired mitochondrial respiration, cardiotoxic reactions and tachyarrhythmias associated with the increased sympathetic tone are factors possibly intensifying myocardial infarction. A particularly important factor is that cannabis use is frequently accompanied by tobacco smoking. In conclusion, additional research is warranted to decipher the mechanisms involved, since cannabis use is being legalized increasingly and Δ9-tetrahydrocannabinol and its synthetic analogue nabilone are indicated for the treatment of various disease states.


Assuntos
Canabinoides , Cannabis , Infarto do Miocárdio , Adolescente , Analgésicos , Agonistas de Receptores de Canabinoides , Canabinoides/efeitos adversos , Cannabis/efeitos adversos , Coração , Humanos , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/tratamento farmacológico
5.
Int J Mol Sci ; 23(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35163351

RESUMO

GPR18 receptor protein was detected in the heart and vasculature and appears to play a functional role in the cardiovascular system. We investigated the effects of the new GPR18 agonists PSB-MZ-1415 and PSB-MZ-1440 and the new GPR18 antagonist PSB-CB-27 on isolated human pulmonary arteries (hPAs) and compared their effects with the previously proposed, but unconfirmed, GPR18 ligands NAGly, Abn-CBD (agonists) and O-1918 (antagonist). GPR18 expression in hPAs was shown at the mRNA level. PSB-MZ-1415, PSB-MZ-1440, NAGly and Abn-CBD fully relaxed endothelium-intact hPAs precontracted with the thromboxane A2 analog U46619. PSB-CB-27 shifted the concentration-response curves (CRCs) of PSB-MZ-1415, PSB-MZ-1440, NAGly and Abn-CBD to the right; O-1918 caused rightward shifts of the CRCs of PSB-MZ-1415 and NAGly. Endothelium removal diminished the potency and the maximum effect of PSB-MZ-1415. The potency of PSB-MZ-1415 or NAGly was reduced in male patients, smokers and patients with hypercholesterolemia. In conclusion, the novel GPR18 agonists, PSB-MZ-1415 and PSB-MZ-1440, relax hPAs and the effect is inhibited by the new GPR18 antagonist PSB-CB-27. GPR18, which appears to exhibit lower activity in hPAs from male, smoking or hypercholesterolemic patients, may become a new target for the treatment of pulmonary arterial hypertension.


Assuntos
Ácidos Araquidônicos , Artéria Pulmonar , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Ácidos Araquidônicos/farmacologia , Humanos , Ligantes , Masculino , Artéria Pulmonar/metabolismo , Receptores Acoplados a Proteínas G/metabolismo
6.
Pharmacol Rep ; 72(3): 756-762, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32333296

RESUMO

BACKGROUND: LY393558 is a combined antagonist of serotonin (5-HT) 5-HT1B receptors and inhibitor of serotonin transporter (SERT). LY393558 reduces 5-HT-induced vasoconstriction and remodelling of rat and/or mouse pulmonary arteries. The aim of our study was to examine the effect of LY393558 on the 5-HT-stimulated vasoconstriction of human pulmonary arteries (hPAs) and to determine the underlying mechanism(s). METHODS: Vascular effects of 5-HT receptor agonists, antagonists and a SERT inhibitor were examined in organ bath studies on intralobar hPAs obtained from patients during resection of lung carcinoma. RESULTS: Serotonin and agonists of the 5-HT1B receptor (5-carboxamidotryptamine, 5-CT) and 5-HT2A receptor (α-methyl-5-HT) contracted endothelium-intact hPAs in a concentration-dependent fashion. The 5-HT1B antagonists SB224289 and GR55562 reduced responses induced by 5-HT and 5-CT and the 5-HT2A antagonist ketanserin inhibited the effects of 5-HT and α-methyl-5-HT. Administration of the SERT inhibitor citalopram (at a concentration that failed to modify the 5-HT-induced vasoconstriction) in combination with SB224289 or GR55562 was more effective in inhibiting the response to 5-HT than the 5-HT1B antagonists alone. LY393558 showed the greatest antagonistic effect against the vasoconstriction elicited by 5-HT, 5-CT and α-methyl-5-HT. CONCLUSIONS: LY393558 reduces the 5-HT-induced contraction antagonizing 5-HT1B and 5-HT2A receptors probably due to synergic interaction between SERT inhibition and 5-HT1B receptor antagonism. Thus, it might represent a valuable future option in the pulmonary arterial hypertension therapy.


Assuntos
Óxidos S-Cíclicos/farmacologia , Artéria Pulmonar/efeitos dos fármacos , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Antagonistas do Receptor 5-HT1 de Serotonina/farmacologia , Antagonistas do Receptor 5-HT2 de Serotonina , Tiadiazinas/farmacologia , Vasoconstrição/efeitos dos fármacos , Idoso , Benzamidas/farmacologia , Citalopram/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Piperidonas/farmacologia , Piridinas/farmacologia , Receptor 5-HT1B de Serotonina , Receptor 5-HT2A de Serotonina , Compostos de Espiro/farmacologia
7.
J Hypertens ; 38(5): 896-911, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31800399

RESUMO

OBJECTIVE: Cannabidiol (CBD) has been suggested as a potential antihypertensive drug. The aim of our study was to investigate its vasodilatory effect in isolated human pulmonary arteries (hPAs) and rat small mesenteric arteries (sMAs). METHODS: Vascular effects of CBD were examined in hPAs obtained from patients during resection of lung carcinoma and sMAs isolated from spontaneously hypertensive (SHR); 11-deoxycorticosterone acetate (DOCA-salt) hypertensive rats or their appropriate normotensive controls using organ bath and wire myography, respectively. RESULTS: CBD induced almost full concentration-dependent vasorelaxation in hPAs and rat sMAs. In hPAs, it was insensitive to antagonists of CB1 (AM251) and CB2 (AM630) receptors but it was reduced by endothelium denudation, cyclooxygenase inhibitors (indomethacin and nimesulide), antagonists of prostanoid EP4 (L161982), IP (Cay10441), vanilloid TRPV1 (capsazepine) receptors and was less potent under KCl-induced tone and calcium-activated potassium channel (KCa) inhibitors (iberiotoxin, UCL1684 and TRAM-34) and in hypertensive, overweight and hypercholesteremic patients. The time-dependent effect of CBD was sensitive to the PPARγ receptor antagonist GW9662. In rats, the CBD potency was enhanced in DOCA-salt and attenuated in SHR. The CBD-induced relaxation was inhibited in SHR and DOCA-salt by AM251 and only in DOCA-salt by AM630 and endothelium denudation. CONCLUSION: The CBD-induced relaxation in hPAs that was reduced in hypertensive, obese and hypercholesteremic patients was endothelium-dependent and mediated via KCa and IP, EP4, TRPV1 receptors. The CBD effect in rats was CB1-sensitive and dependent on the hypertension model. Thus, modification of CBD-mediated responses in disease should be considered when CBD is used for therapeutic purposes.


Assuntos
Anti-Hipertensivos/farmacologia , Canabidiol/farmacologia , Artérias Mesentéricas/efeitos dos fármacos , Artéria Pulmonar/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Idoso , Animais , Pressão Sanguínea/efeitos dos fármacos , Acetato de Desoxicorticosterona , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Hipertensão/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Ratos , Ratos Endogâmicos SHR
8.
Life Sci ; 204: 20-45, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29729263

RESUMO

The endocannabinoid system is up-regulated in numerous pathophysiological states such as inflammatory, neurodegenerative, gastrointestinal, metabolic and cardiovascular diseases, pain, and cancer. It has been suggested that this phenomenon primarily serves an autoprotective role in inhibiting disease progression and/or diminishing signs and symptoms. Accordingly, enhancement of endogenous endocannabinoid tone by inhibition of endocannabinoid degradation represents a promising therapeutic approach for the treatment of many diseases. Importantly, this allows for the avoidance of unwanted psychotropic side effects that accompany exogenously administered cannabinoids. The effects of endocannabinoid metabolic pathway modulation are complex, as endocannabinoids can exert their actions directly or via numerous metabolites. The two main strategies for blocking endocannabinoid degradation are inhibition of endocannabinoid-degrading enzymes and inhibition of endocannabinoid cellular uptake. To date, the most investigated compounds are inhibitors of fatty acid amide hydrolase (FAAH), an enzyme that degrades the endocannabinoid anandamide. However, application of FAAH inhibitors (and consequently other endocannabinoid degradation inhibitors) in medicine became questionable due to a lack of therapeutic efficacy in clinical trials and serious adverse effects evoked by one specific compound. In this paper, we discuss multiple pathways of endocannabinoid metabolism, changes in endocannabinoid levels across numerous human diseases and corresponding experimental models, pharmacological strategies for enhancing endocannabinoid tone and potential therapeutic applications including multi-target drugs with additional targets outside of the endocannabinoid system (cyclooxygenase-2, cholinesterase, TRPV1, and PGF2α-EA receptors), and currently used medicines or medicinal herbs that additionally enhance endocannabinoid levels. Ultimately, further clinical and preclinical studies are warranted to develop medicines for enhancing endocannabinoid tone.


Assuntos
Moduladores de Receptores de Canabinoides/farmacologia , Endocanabinoides/fisiologia , Receptores de Canabinoides/efeitos dos fármacos , Doença , Endocanabinoides/biossíntese , Humanos
9.
Cell Physiol Biochem ; 46(2): 727-739, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29621749

RESUMO

BACKGROUND/AIMS: Recent interest in the use of cannabinoids as therapeutic agents has revealed the involvement of the endogenous cannabinoid system (ECS) in the regulation of the cardiovascular system in hypertension. Abnormalities in glucose metabolism and insulin action are commonly detected in hypertensive animals. Thus, potential antihypertensive drugs should be investigated with respect to modulation of glucose homeostasis. Therefore, the aim of the present study was to evaluate the effects of the ECS activation after chronic fatty acid amide hydrolase inhibitor (URB597) administration on plasma glucose and insulin concentrations as well as parameters of myocardial glucose metabolism in the deoxycorticosterone acetate (DOCA)-salt hypertensive rats, an animal model of secondary hypertension. METHODS: Hypertension was induced by DOCA (25mg/kg) injections and addition of 1% NaCl in the drinking water for six weeks. Chronic activation of the ECS was performed by URB597 (1mg/kg) injections for two weeks. We examined fasting plasma levels of insulin (ELISA), glucose and intramyocardial glycogen (colorimetric method). Expressions of glucose transporters (GLUT1, 4) and selected proteins engaged in GLUT translocation as well as glucose metabolism were determined using Western blotting. RESULTS: Hypertension induced hypoinsulinemia with concomitant lack of significant changes in glycemia, reduced intramyocardial glycogen content and increased pyruvate dehydrogenase (PDH) expression in the cardiac muscle. Importantly, chronic URB597 administration in the hypertensive rats increased insulin concentration, elevated plasmalemmal GLUT1 and GLUT4 expression and concomitantly improved myocardial glycogen storage. CONCLUSION: Chronic administration of fatty acid amide hydrolase (FAAH) inhibitor has potential protective properties on myocardial glucose metabolism in hypertension.


Assuntos
Benzamidas/uso terapêutico , Carbamatos/uso terapêutico , Glucose/metabolismo , Hipertensão/patologia , Miocárdio/metabolismo , Animais , Benzamidas/farmacologia , Glicemia/análise , Carbamatos/farmacologia , Acetato de Desoxicorticosterona/toxicidade , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Glicogênio/análise , Hipertensão/induzido quimicamente , Hipertensão/tratamento farmacológico , Insulina/sangue , Cetona Oxirredutases/metabolismo , Masculino , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Miocárdio/patologia , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar
10.
Naunyn Schmiedebergs Arch Pharmacol ; 387(5): 477-86, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24682422

RESUMO

Endocannabinoids contract, relax or do not affect vessels with different calibre and tone in the pulmonary circulation in four species. The aim of the present study was to determine the mechanisms involved in the anandamide-induced relaxation of human pulmonary arteries (hPAs). Studies were performed in the isolated hPAs pre-constricted with the prostanoid TP receptor agonist, U-46619. To detect fatty acid amide hydrolase (FAAH) expression, Western blots were used. Anandamide concentration dependently relaxed the endothelium-intact hPAs pre-constricted with U-46619. The anandamide-induced relaxation was virtually abolished by removal of the endothelium and strongly attenuated by inhibitors of cyclooxygenases (indomethacin, COX-1/COX-2, and nimesulide, COX-2), nitric oxide synthase (N (G) -nitro-L-arginine methyl ester) given separately or in combination, FAAH (URB597), and the prostanoid IP receptor antagonist, RO1138452. The anandamide-evoked relaxation in the endothelium-intact vessels was attenuated in KCl pre-constricted preparations or by the inhibitor of large-conductance Ca(2+)-activated K(+) channels, iberiotoxin. In experiments performed in the presence of URB597 to exclude effects of anandamide metabolites, the antagonist of the endothelial cannabinoid receptor, O-1918, diminished the anandamide-evoked relaxation whereas the antagonists of cannabinoid CB1, CB2 and vanilloid TRPV1 receptors, AM251, SR144528 and capsazepine, respectively, had no effect. Western blot studies revealed the occurrence of FAAH protein in the hPAs. The present study shows that anandamide breakdown products, cyclooxygenase pathways, nitric oxide, potassium channels and the O-1918-sensitive cannabinoid receptor play a role in the anandamide-induced relaxation of the hPAs with intact endothelium.


Assuntos
Ácidos Araquidônicos/farmacologia , Endocanabinoides/farmacologia , Endotélio Vascular/fisiologia , Alcamidas Poli-Insaturadas/farmacologia , Artéria Pulmonar/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Idoso , Amidoidrolases/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/fisiologia , Peptídeos/farmacologia , Artéria Pulmonar/fisiologia , Serotonina/farmacologia
11.
Naunyn Schmiedebergs Arch Pharmacol ; 386(5): 445-53, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23483194

RESUMO

It has been suggested that activation of nuclear peroxisome proliferator-activated receptors γ (PPARγ) may represent a new strategy for the treatment of pulmonary arterial hypertension. It has been demonstrated that PPARγ activation relaxed the isolated mouse pulmonary artery. The aims of the present study were to examine whether and to which extent the two PPARγ agonists rosiglitazone and pioglitazone relax the isolated human pulmonary artery and to investigate the underlying mechanism(s). Isolated human pulmonary arteries were obtained from patients without clinical evidence of pulmonary hypertension during resection of lung carcinoma. Vasodilatory effects of PPARγ agonists were examined on endothelium-intact or endothelium-denuded vessels preconstricted with the thromboxane prostanoid receptor agonist U-46619. Rosiglitazone and pioglitazone (0.01-100 µM) caused a concentration- and/or time-dependent full relaxation of U-46619-preconstricted vessels. The rosiglitazone-induced relaxation was attenuated by the PPARγ antagonist GW9662 1 µM, endothelium denudation, the nitric oxide synthase inhibitor L-NAME 300 µM, the cyclooxygenase inhibitor indomethacin 10 µM, and the KATP channel blocker glibenclamide 10 µM. The prostacyclin IP receptor antagonist RO1138452 1 µM shifted the concentration-response curve for rosiglitazone to the right. The PPARγ agonists pioglitazone and rosiglitazone relax human pulmonary arteries. The rosiglitazone-induced vasorelaxation is partially endothelium-dependent and involves PPARγ receptors, arachidonic acid degradation products, nitric oxide, and KATP channels. Thus, the relaxant effect of PPARγ agonists in human pulmonary arteries may represent a new therapeutic target in pulmonary arterial hypertension.


Assuntos
Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , PPAR gama/agonistas , PPAR gama/fisiologia , Artéria Pulmonar/fisiologia , Vasodilatação/fisiologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Cultura de Órgãos , Artéria Pulmonar/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
12.
J Pharmacol Exp Ther ; 326(3): 912-9, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18567834

RESUMO

Methanandamide (MAEA), the stable analog of the endocannabinoid anandamide, has been proven in Xenopus oocytes to allosterically inhibit the function of the alpha7-nicotinic acetylcholine receptors (nAChRs) in a cannabinoid (CB) receptor-independent manner. The present study aimed at demonstrating that this mechanism can be activated in vivo. In anesthetized and vagotomized pithed rats treated with atropine, we determined the tachycardic response to electrical stimulation of preganglionic sympathetic nerves via the pithing rod or to i.v. nicotine (0.7 micromol/kg) activating nAChRs on the cardiac postganglionic sympathetic neurons. MAEA (3 and 10 micromol/kg) inhibited the electrically induced tachycardia (maximally by 15-20%; abolished by the CB(1) receptor antagonist AM 251 [N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide]; 3 micromol/kg) in pentobarbitone-anesthetized pithed rats, but not in urethane-anesthetized pithed rats, which, thus, are suitable to study the CB(1) receptor-independent inhibition of nicotine-evoked tachycardia. The subunit-nonselective nAChR antagonist hexamethonium (100 micromol/kg) and the selective alpha7-subunit antagonist methyllycaconitine (MLA; 3 and 10 micromol/kg) decreased the nicotine-induced tachycardia by 100 and 40%, respectively (maximal effects), suggesting that nAChRs containing the alpha7-subunit account for 40% of the nicotine-induced tachycardia. MAEA (3 micromol/kg) produced an AM 251-insensitive inhibition (maximum again by 40%) of the nicotine-induced tachycardia. Simultaneous or sequential coadministration of MLA and MAEA inhibited the nicotine-induced tachycardia to the same extent (maximally by 40%) as each of the drugs alone. In conclusion, according to nonadditivity of the effects, MAEA mediates in vivo inhibition by the same receptors as MLA, namely alpha7-subunit-containing nAChRs, although at an allosteric instead of the orthosteric site.


Assuntos
Ácidos Araquidônicos/química , Ácidos Araquidônicos/farmacologia , Subunidades Proteicas/antagonistas & inibidores , Subunidades Proteicas/fisiologia , Receptores Nicotínicos/fisiologia , Regulação Alostérica/efeitos dos fármacos , Regulação Alostérica/fisiologia , Animais , Relação Dose-Resposta a Droga , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Masculino , Nicotina/farmacologia , Subunidades Proteicas/agonistas , Ratos , Ratos Wistar , Receptor Nicotínico de Acetilcolina alfa7
13.
J Hypertens ; 25(11): 2240-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17921818

RESUMO

BACKGROUND: The endocannabinoid anandamide is implicated in the pathogenesis of hypotension in haemorrhagic, endotoxic, and cardiogenic shock. It has been demonstrated in animal, but not in human, vessels that the vasodilatory effects of anandamide and abnormal cannabidiol are partially mediated by an as yet unidentified endothelial cannabinoid receptor. Our study was performed to examine the influence of abnormal cannabidiol on the human pulmonary artery. METHODS: Isolated human pulmonary arteries were obtained from patients without clinical evidence of pulmonary hypertension during resection of lung carcinoma. Vasodilatory effects of abnormal cannabidiol were examined on endothelium-intact vessels preconstricted with serotonin or potassium chloride. RESULTS: Anandamide and abnormal cannabidiol relaxed serotonin-preconstricted vessels concentration-dependently. The effect of abnormal cannabidiol was reduced by endothelium denudation, pertussis toxin and two antagonists of the novel endothelial receptor, cannabidiol and O-1918, but not by the nitric oxide synthase inhibitor L-NAME given together with the cyclooxygenase inhibitor indomethacin. It was also diminished by blockade of calcium-activated potassium channels by the nonselective blocker tetraethylammonium or by combination of selective blockers of small (apamin) and intermediate and large (charybdotoxin) conductance calcium-activated potassium channels. The potency of abnormal cannabidiol to relax vessels was lower in potassium chloride than in serotonin-preconstriced preparations. CONCLUSIONS: Abnormal cannabidiol relaxes human pulmonary arteries in an endothelium-independent and endothelium-dependent manner. The latter component is probably mediated via the putative endothelial cannabinoid receptor, activation of which may release endothelium-derived hyperpolarizing factor, which in turn acts via calcium-activated potassium channels. Abnormal cannabidiol is behaviourally inactive; it may have a therapeutic implication in vascular diseases, especially in the treatment of pulmonary hypertension.


Assuntos
Endotélio Vascular/fisiologia , Artéria Pulmonar/fisiologia , Receptores de Canabinoides/fisiologia , Vasodilatação , Ácidos Araquidônicos/farmacologia , Relação Dose-Resposta a Droga , Endocanabinoides , Feminino , Humanos , Técnicas In Vitro , Indometacina/farmacologia , Masculino , Pessoa de Meia-Idade , NG-Nitroarginina Metil Éster/farmacologia , Toxina Pertussis/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Cloreto de Potássio/farmacologia , Artéria Pulmonar/efeitos dos fármacos , Receptores de Canabinoides/análise , Resorcinóis/farmacologia , Serotonina/farmacologia , Vasodilatação/efeitos dos fármacos
14.
Endokrynol Pol ; 56(3): 225-32, 2005.
Artigo em Polonês | MEDLINE | ID: mdl-16350714

RESUMO

UNLABELLED: Complete androgenic blockade used in the treatment of advanced prostatic carcinoma can be attained by administration of antiandrogens in orchidectomized patients or by combined therapy with LH-RH analogs and antiandrogens. The treatment, however, decreases the influence of both androgens end estrogens on bone tissue and may result in bone mass loss and increased propensity to fractures. The purpose of the study was to determine the influence of complete androgenic blockade on bone mass and skeletal metabolism in men with advanced prostatic carcinoma and to assess whether 1alpha-OH vitamin D3 (1alpha-OHD3) together with calcium supplementation is able to prevent bone mass loss in men treated with complete androgenic blockade. 51 patients with advanced prostatic carcinoma, with skeletal metastases, aged 44 - 86, mean 68 ys were included into a 12-month prospective study. All patients were treated with orchidectomy followed by therapy with flutamide in a dose of 750 mg daily. 26 patients were additionally given 1alpha-OHD3 in a dose of 0.5 microg/d and calcium carbonate in an initial dose of 1 g daily. It was found that the 12-month treatment with complete androgenic blockade resulted in a decrease in bone mineral density (BMD) by 8.1% in the lumbar spine, by 6.3% in the femoral neck and by 3.5% in the total skeleton. Therapy with 1alpha-OHD3 and CaCO3 caused complete inhibition of bone tissue loss in the lumbar spine and resulted in an increase in BMD by 2.2% in femoral neck and by 1.9% in the total skeleton. None of the examined patients experienced any skeletal fractures. In both groups of patients a prompt decrease in serum alkaline phosphatase activity - a marker of osteoblast activity and an increase in fasting urine calcium creatinine ratio indicating acceleration of bone resorption were found. CONCLUSIONS: in patients with advanced prostatic carcinoma treated with complete androgenic blockade acceleration of bone mass loss is observed; treatment with 1alpha-OHD3 and CaCO3 is able to prevent both trabecular and compact bone loss.


Assuntos
Antineoplásicos Hormonais/efeitos adversos , Conservadores da Densidade Óssea/administração & dosagem , Cálcio da Dieta/administração & dosagem , Hidroxicolecalciferóis/administração & dosagem , Orquiectomia/efeitos adversos , Osteomalacia/prevenção & controle , Neoplasias da Próstata/terapia , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Androgênios/administração & dosagem , Antagonistas de Androgênios/efeitos adversos , Antineoplásicos Hormonais/administração & dosagem , Densidade Óssea/efeitos dos fármacos , Regeneração Óssea/efeitos dos fármacos , Cálcio/sangue , Quimioterapia Combinada , Flutamida/administração & dosagem , Flutamida/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Osteomalacia/etiologia , Estudos Prospectivos
15.
Otolaryngol Pol ; 59(1): 43-7, 2005.
Artigo em Polonês | MEDLINE | ID: mdl-15915918

RESUMO

All cases of malignant tumours of the pharynx (excluding tumours of the tongue) were analyzed based on the retrospective data from the 5 clinical centers in Poland from the years 1992-2001. A considerable--over 50% increase in morbidity was found out regarding particularly tumours of the oropharynx. In the analyzed material there is a predominance of males (3:1) and the peak of morbidity significantly falls. The subjects with advanced tumours of the pharynx made 26% of the studied group. The most common histopathological diagnosis was squamous cell carcinoma and the most common site--the oropharynx, in particularly the tonsil. The data the center in Katowice, where tumours of the hypopharynx have been predominant in the last few years, may point a similar tendency in the other centers in the future.


Assuntos
Carcinoma de Células Escamosas/epidemiologia , Neoplasias Faríngeas/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/epidemiologia , Neoplasias Faríngeas/diagnóstico , Polônia/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Distribuição por Sexo , Análise de Sobrevida , Neoplasias Tonsilares/epidemiologia
16.
Otolaryngol Pol ; 57(2): 185-9, 2003.
Artigo em Polonês | MEDLINE | ID: mdl-12894421

RESUMO

There is a clear tendency to diagnose squamous cell carcinoma of the head and neck more frequently in patients below 45 years of age. These neoplasms in "young adults" seem to be more aggressive with rapid progression, frequent reappearance after treatment and worse prognosis than is observed in older patient population. This preliminary report presents results of retrospective, multivariable analysis of patients below 45 years of age with squamous cell carcinoma of the head and neck. The special focus of the study were: disease progression (T), regional node and distant metastases (N,M), tobacco and alcohol consumption, environmental factors, concomitant diseases, kind of surgical technique and tumour histology.


Assuntos
Carcinoma de Células Escamosas/fisiopatologia , Carcinoma de Células Escamosas/secundário , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/fisiopatologia , Adolescente , Adulto , Fatores Etários , Consumo de Bebidas Alcoólicas/efeitos adversos , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/cirurgia , Progressão da Doença , Exposição Ambiental/efeitos adversos , Feminino , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Masculino , Análise Multivariada , Estadiamento de Neoplasias , Polônia/epidemiologia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Fumar/efeitos adversos , Fatores Socioeconômicos , Fatores de Tempo
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