Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 127
Filtrar
2.
J Dent Res ; 94(1): 93-100, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25348543

RESUMO

The expression and assembly of the extracellular matrix are profoundly associated with adaptive and pathological responses of the temporomandibular joint (TMJ). To better understand the adaptive responses of the TMJ disc to mechanical loading, we examined the expression of 2 modular proteoglycans and 10 small leucine-rich proteoglycans (SLRPs) at the mRNA and protein levels and determined the contents of proteoglycan-related glycosaminoglycans (GAGs) in rat TMJ discs in response to altered mechanical loading caused by an incisal bite plane. One hundred thirty 7-week-old male Wistar rats were assigned to control and bite plane groups. TMJ disc thickness and the intensity of toluidine blue staining of metachromasia increased in the posterior band after 2 weeks of wearing the bite plane. GAG content increased significantly in the bite plane group after 2 weeks. Quantitative real-time RT-PCR (reverse transcription polymerase chain reaction) analysis indicated that biglycan and chondroadherin mRNA levels increased after 2 weeks and that the level of decorin mRNA increased at 4 weeks. Versican mRNA levels increased after 3 weeks, particularly for the V0 and V1 versican isoforms, which carry more GAG attachment sites than do the V2 and V3 isoforms. Western analysis demonstrated a corresponding increase in the levels of versican, biglycan, and decorin core proteins at 4 weeks in the bite plane group. These results indicate that mechanical loading differentially influences proteoglycan mRNA expression and protein accumulation in the TMJ disc. The change in proteoglycan mRNA and protein levels may lead to the modulation of matrix-matrix and cell-matrix interactions and has important biological significance for adaptation to complicated biomechanical requirements and for tissue maintenance in the TMJ disc.


Assuntos
Proteoglicanas/análise , Disco da Articulação Temporomandibular/química , Suporte de Carga/fisiologia , Adaptação Fisiológica/fisiologia , Agrecanas/análise , Animais , Biglicano/análise , Junções Célula-Matriz/química , Proteoglicanas de Sulfatos de Condroitina/análise , Corantes , Decorina/análise , Proteínas da Matriz Extracelular/análise , Fibromodulina , Glicoproteínas/análise , Peptídeos e Proteínas de Sinalização Intercelular/análise , Sulfato de Queratano/análise , Lumicana , Masculino , Aparelhos Ortodônticos , Isoformas de Proteínas/análise , Distribuição Aleatória , Ratos , Ratos Wistar , Estresse Mecânico , Disco da Articulação Temporomandibular/anatomia & histologia , Fatores de Tempo , Cloreto de Tolônio , Versicanas/análise
3.
Neuropharmacology ; 22(7): 813-7, 1983 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6225960

RESUMO

Rats exhibited a marked suppression of motor activity when placed in the same chamber where they had been given electric shocks. Administration of apomorphine-HCl (0.1, 0.5 and 1.0 mg/kg, i.p.) attenuated the conditioned suppression, dose-dependently, but did not facilitate motor activity of control (i.e. non-shocked) rats. Methamphetamine-HCl (0.1, 0.5 and 1 mg/kg, i.p.) increased motor activity of both the shocked and non-shocked rats, in a dose-related manner. Haloperidol (0.3 and 1 mg/kg, i.p.), but not chlorpromazine-HCl (5 mg/kg, i.p.), enhanced the conditioned-suppression response. Atropine-sulfate (5 and 10 mg/kg, i.p.), p-chlorophenylalanine (300 mg/kg, i.p.) and alpha-methyl-p-tyrosine (100 mg/kg, i.p.) were slightly effective in reducing the conditioned-suppression response. Apomorphine- and methamphetamine-induced reduction of the conditioned-suppression response was inhibited by pretreatment with haloperidol. When catecholamine-synthesizing processes in rats were inhibited by pretreatment with alpha-methyl-p-tyrosine, or alpha-adrenergic receptor sites were blocked by pretreatment with phenoxybenzamine, the effect of methamphetamine, but not that of apomorphine, was reduced. Therefore, enhancement of dopaminergic neurotransmission may be responsible for attenuation of the conditioned-suppression response.


Assuntos
Apomorfina/farmacologia , Condicionamento Operante/efeitos dos fármacos , Metanfetamina/farmacologia , Animais , Atropina/farmacologia , Clorpromazina/farmacologia , Emoções/efeitos dos fármacos , Fenclonina/farmacologia , Haloperidol/farmacologia , Masculino , Metiltirosinas/farmacologia , Ratos , Ratos Endogâmicos , alfa-Metiltirosina
4.
Neuropharmacology ; 21(12): 1283-9, 1982 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7155310

RESUMO

Mice were found to exhibit a marked suppression of motor activity when placed into the same experimental chamber in which they had previously received electrical shocks. This suppression was found to be a stable response when mice, 6-8 weeks of age, received shocks of frequencies of 1/10 or 1/30 Hz, and their motility was examined 24 hr after the delivery of the shock in the same experimental chamber. Control experiments indicated that the mice exhibited similar degrees of locomotor activity, compared to non-shocked mice, that were placed into a different experimental chamber than from the one in which they had previously received electrical shocks. Thus, the suppression of motor activity appeared to be a conditioned emotional response to the environment previously associated with delivery of shock. Morphine, codeine, and pethidine, but not pentazocine and aminopyrine, attenuated the conditioned suppression in a dose-related manner in the shocked mice. The effect of morphine was completely antagonized by pretreatment with naloxone or levallorphan. Thus, it is possible that the opiate-induced reduction of conditioned suppression is mediated by opiate receptor sites.


Assuntos
Analgésicos/farmacologia , Condicionamento Psicológico/efeitos dos fármacos , Envelhecimento , Animais , Eletrochoque , Emoções/efeitos dos fármacos , Levalorfano/farmacologia , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Naloxona/farmacologia
5.
Neuropharmacology ; 24(4): 285-90, 1985 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-4039801

RESUMO

Mice experienced to electric shock, exhibited a marked suppression of motor activity when placed in the same cage 24 hr after administration of shocks. Acute administration of imipramine-HCl (10 mg/kg, i.p.), desipramine-HCl (5 and 10 mg/kg, i.p.) and amitriptyline-HCl (5 and 10 mg/kg, i.p.) caused marked reduction of the conditioned suppression of shocked mice, but reduced the motor activity of the non-shocked mice. Maprotiline, mianserin and dimetacrine did not cause reduction of the conditioned suppression. Nialamide (100 mg/kg, i.p.) and pargyline-HCl (100 and 200 mg/kg, i.p.) caused marked reduction of the conditioned suppression but did not increase the motor activity of the non-shocked mice, and tranylcypromine-HCl (10 and 20 mg/kg, i.p.) did not cause reduction of the conditioned suppression. Diphenhydramine-HCl (10 and 20 mg/kg, i.p.) reduced the conditioned suppression of shocked mice in a dose-related manner. Chronic administration of imipramine-HCl (1 and 5 mg/kg, i.p.) for 14 days significantly reduced the conditioned suppression but did not influence the motility rate of the non-shocked mice. Also, chronic administration of amitriptyline (1 mg/kg, i.p.), desipramine (5 mg/kg, i.p.) and dimetacrine (10 mg/kg, i.p.), for 10 days, significantly reduced the conditioned suppression, but did not influence the motility rate of the non-shocked mice. Chronic administration of maprotiline reduced the conditioned suppression. On the other hand, chronic administration of mianserin (5 mg/kg, i.p.) and diphenhydramine (10 mg/kg, i.p.) did not cause a reduction of the conditioned suppression.


Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo/tratamento farmacológico , Acridinas/uso terapêutico , Amitriptilina/uso terapêutico , Animais , Desipramina/uso terapêutico , Difenidramina/uso terapêutico , Modelos Animais de Doenças , Eletrochoque , Etanol/uso terapêutico , Humanos , Imipramina/uso terapêutico , Masculino , Maprotilina/uso terapêutico , Mianserina/uso terapêutico , Camundongos , Atividade Motora/efeitos dos fármacos , Nialamida/uso terapêutico , Pargilina/uso terapêutico , Tranilcipromina/uso terapêutico
6.
J Hypertens ; 19(10): 1877-82, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11593110

RESUMO

OBJECTIVES: Patients with chronic renal failure are restricted to mild physical activity and tend to a lack of exercise. However, there have been few reports regarding the influence of chronic exercise on the progression of renal disease. Similarly, there are few animal models concerned with the effect of exercise training on improving renal function. Therefore, we assessed the renal effects of moderate chronic treadmill exercise in a remnant kidney model of spontaneously hypertensive rats (SHR) with chronic renal failure. We also assessed the effects of exercise and antihypertensive therapy on renal function. DESIGN AND METHODS: Eight-week-old SHR were subjected to 5/6 nephrectomy by removal of the left kidney and excision of two-thirds of the right kidney. The rats were divided into four groups: (i) no exercise (Non-EX); (ii) moderate exercise with treadmill running (20 m/min, 0 grade incline for 60 min) (EX); (iii) EX with an angiotensin converting enzyme (ACE) inhibitor, enalapril (2 mg/kg per day, i.p.); and (iv) EX with an angiotensin receptor antagonist, losartan (5 mg/kg per day, i.p.), for 4 weeks. RESULTS: Chronic EX significantly attenuated the increase in proteinuria (P < 0.01) and significantly protected against increases in the index of glomerular sclerosis (IGS). Both enalapril and losartan with EX significantly decreased blood pressure (P < 0.001), and further decreased the IGS. In the stepwise multiple regression analysis, only antihypertensive drug remained in the model as a significant predictor of IGS (P < 0.0001). In contrast, exercise, antihypertensive drug and mean systolic blood pressure (weeks 1-4) remained in the model as a significant predictors of mean proteinuria (weeks 1-4) (all P < 0.0001). CONCLUSIONS: These results suggest that exercise does not worsen renal function and has renal-protective effects in this model of rats. Moreover, the antihypertensive therapy has additional renal-protective effects in this model of rats.


Assuntos
Anti-Hipertensivos/farmacologia , Hipertensão/complicações , Falência Renal Crônica/complicações , Falência Renal Crônica/fisiopatologia , Rim/efeitos dos fármacos , Rim/fisiopatologia , Atividade Motora , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Enalapril/farmacologia , Hipertensão/fisiopatologia , Losartan/farmacologia , Masculino , Proteinúria/urina , Ratos , Ratos Endogâmicos SHR , Fatores de Tempo
7.
Am J Hypertens ; 13(3): 298-306, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10777035

RESUMO

We assessed the renal and cardiac benefits of cicletanine (CIC), a furopyridine derivative drug with diuretic and antihypertensive properties, in diabetic spontaneously hypertensive rats with renal impairment. Uninephrectomized streptozotocin (STZ)-diabetic spontaneously hypertensive Izmo rats (SHRIzm) (10 weeks old) were randomly assigned to receive vehicle or CIC (100 mg/kg/day, orally), and age-matched, uninephrectomized STZ diabetic Wistar-Kyoto Izmo rats (WKYIzm) were assigned to receive vehicle for up to 12 weeks. Blood pressure increased progressively in diabetic SHRIzm but not in diabetic WKYIzm. Urinary albumin excretion increased significantly in both diabetic SHRIzm and diabetic WKYIzm throughout the experiment. The antihypertensive effect of CIC was not significantly observed in diabetic SHRIzm. However, the subdepressor doses of CIC significantly decreased urinary albumin excretion, serum creatinine, and blood urea nitrogen in diabetic SHRIzm. These results were confirmed by morphological analysis of kidneys in each group of rats. The index of focal glomerular sclerosis (FGS) in diabetic SHRIzm was significantly higher than that in diabetic WKYIzm. The CIC treatment significantly and effectively protected against an increase in the index of FGS in diabetic SHRIzm. Moreover, CIC treatment significantly attenuated the increase in the heart weight to body weight ratio in diabetic SHRIzm. Treatment with CIC did not affect urinary and blood glucose concentrations at this dose. These results suggest that CIC has a renal-protective action, which is not related to improvement of diabetes or improvement of high blood pressure in diabetic rats with hypertension. The action might be due to the reduction of intraglomerular capillary pressure or protection of the renal glomerular vascular endothelial cell injury and mesangial cell injury through stimulation of PGI2 generation or elimination of free radicals, although the mechanism remains to be further investigated.


Assuntos
Anti-Hipertensivos/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Hipertensão/tratamento farmacológico , Rim/efeitos dos fármacos , Piridinas/farmacologia , Albuminúria/urina , Análise de Variância , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Nitrogênio da Ureia Sanguínea , Peso Corporal/efeitos dos fármacos , Creatinina/sangue , Diabetes Mellitus Experimental/fisiopatologia , Diástole , Relação Dose-Resposta a Droga , Frequência Cardíaca/efeitos dos fármacos , Hipertensão/fisiopatologia , Rim/patologia , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/patologia , Necrose , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Sístole , Fatores de Tempo
8.
Hypertens Res ; 18 Suppl 1: S147-50, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8529046

RESUMO

Dopamine (DA) has been shown to be an endogenous catecholamine that promotes natriuresis by activating tubular DA receptors, but its role on natriuresis appears to be equivocal, and the precise mechanisms and signaling pathway of multiple DA's receptor subtypes are not yet clarified. We used low dose of DA intravenously in saline (S) volume-expanded dogs to see the alterations in natriuresis. The results showed that there is a critical dose that induces no enhancement of natriuresis of volume expansion, and that the lower and higher doses of DA produced relatively larger natriuresis. Pretreatment of metoclopramide (MCP) in this settings caused even higher and significant increases of natriuresis. In conclusion, DA seems to determine tonically the level of natriuresis in saline-expanded dogs. DA may exert a dual effect on signal transduction pathways such that one leading to antinatriuresis with high affinity and the other to natriuresis with low affinity signaling cascades for DA. MCP may block the antinatriuretic limb of the signaling pathway.


Assuntos
Volume Sanguíneo/fisiologia , Dopamina/fisiologia , Natriurese/fisiologia , Animais , Volume Sanguíneo/efeitos dos fármacos , Cães , Antagonistas de Dopamina/farmacologia , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Metoclopramida/farmacologia , Natriurese/efeitos dos fármacos , Substitutos do Plasma/farmacologia , Renina/sangue , Transdução de Sinais/efeitos dos fármacos , Cloreto de Sódio
9.
Brain Res ; 275(2): 389-91, 1983 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-6626989

RESUMO

Rats showed marked suppression of motor activity when placed in the cage where they were previously shocked. When 14 days of consecutive administration of haloperidol was terminated, the conditioned suppression was significantly reduced. Such an effect of chronic haloperidol treatment was antagonized by pretreatment with naloxone. Thus, it is possible that the opiate-like system is involved in a part of the reduction of conditioned suppression.


Assuntos
Condicionamento Operante/efeitos dos fármacos , Haloperidol/farmacologia , Aprendizagem/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Naloxona/farmacologia , Animais , Antagonismo de Drogas , Eletrochoque , Masculino , Ratos , Ratos Endogâmicos
10.
Eur J Pharmacol ; 215(2-3): 253-7, 1992 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-1396988

RESUMO

The purpose of this study was to investigate the interactions of compounds structurally related to imidazoline at K+ channels located in the rat portal vein. Nicorandil, a K+ channel activator, dose dependently inhibited spontaneous contractions of the isolated rat portal vein. Glibenclamide (0.1-1 microM), an ATP-sensitive K+ channel blocker, competitively antagonized the response to nicorandil, whereas methylene blue (10 microM), a guanylate cyclase inhibitor, did not. Phentolamine, antazoline, tolazoline, and midaglizole also shifted the dose-response curve for nicorandil to the right in the dose range of 1-100 microM. The rank order of potency was glibenclamide much greater than phentolamine = antazoline = midaglizole greater than tolazoline. In contrast, clonidine, idazoxan, imidazole, 1-benzylimidazole, and yohimbine were ineffective. In addition, cromakalim (1-100 nM), a selective K+ channel activator, also inhibited spontaneous contractions of the rat portal vein, and this effect was antagonized by phentolamine in a similar way to that found with nicorandil. These results suggest that some 2-substituted imidazolines, including phentolamine, possibly act as K+ channel blockers, like glibenclamide, in vascular smooth muscle.


Assuntos
Imidazóis/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Niacinamida/análogos & derivados , Animais , Benzopiranos/antagonistas & inibidores , Benzopiranos/farmacologia , Cromakalim , Técnicas In Vitro , Masculino , Contração Muscular/efeitos dos fármacos , Niacinamida/antagonistas & inibidores , Niacinamida/farmacologia , Nicorandil , Veia Porta/efeitos dos fármacos , Canais de Potássio/efeitos dos fármacos , Pirróis/antagonistas & inibidores , Pirróis/farmacologia , Ratos , Ratos Wistar
11.
Eur J Pharmacol ; 238(2-3): 283-9, 1993 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-8104810

RESUMO

MPC-1304 is a novel Ca2+ entry blocker of the 1,4-dihydropyridine type. In the present study, the effect of oral administration of MPC-1304 on alpha-adrenoceptor-mediated pressor responses was examined in pithed rats and compared with that of nifedipine. Drugs were administered orally to conscious animals before pithing. MPC-1304 (0.3-3 mg/kg) and nifedipine (1-10 mg/kg) inhibited pressor responses to norepinephrine, phenylephrine (alpha 1-adrenoceptor agonist), UK-14304 (alpha 2-adrenoceptor agonist), and sympathetic nerve (spinal cord segments) stimulation. MPC-1304 was roughly 3 times more potent than nifedipine in inhibiting these responses. The inhibitory effect of MPC-1304 (3 mg/kg) on the pressor response to UK-14304 lasted longer than that of nifedipine (3 mg/kg). At the same time, plasma concentrations of MPC-1304 were lower than those of nifedipine. These results suggest that MPC-1304 has a great ability to inhibit pressor responses to norepinephrine and peripheral sympathetic stimulation after its oral administration, and that this effect of MPC-1304 is closely correlated with its potent antihypertensive activity.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Di-Hidropiridinas/farmacologia , Receptores Adrenérgicos alfa/fisiologia , Administração Oral , Agonistas alfa-Adrenérgicos/farmacologia , Animais , Tartarato de Brimonidina , Bloqueadores dos Canais de Cálcio/administração & dosagem , Estado de Descerebração , Di-Hidropiridinas/administração & dosagem , Estimulação Elétrica , Nifedipino/administração & dosagem , Nifedipino/farmacologia , Norepinefrina/farmacologia , Fenilefrina/farmacologia , Quinoxalinas/farmacologia , Ratos , Ratos Wistar , Medula Espinal/efeitos dos fármacos , Medula Espinal/fisiologia , Sistema Nervoso Simpático/efeitos dos fármacos
12.
Eur J Pharmacol ; 235(1): 69-74, 1993 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-8519282

RESUMO

The Ca2+ entry blocking effects of MPC-1304, a new Ca2+ entry blocker of the 1,4-dihydropyridine type, and of its (S) and (R) enantiomers and metabolites were examined on Ca(2+)-induced contractions in isolated rabbit arteries. The Ca2+ entry blocking activity of the (S) enantiomer of MPC-1304 was approximately 150 times greater than that of its (R) enantiomer. Likewise, the antihypertensive effect of the (S) enantiomer was twice as great as that of MPC-1304 (racemate) in conscious spontaneously hypertensive rats, while the (R) enantiomer was ineffective. Thus, most of the pharmacological activity of MPC-1304 resides in its (S) configuration. The main metabolic products of MPC-1304 also inhibited the Ca(2+)-induced contraction in the isolated vascular smooth muscles. These active metabolites showed a stereoselectivity similar to that of MPC-1304 for Ca2+ entry blocking activity, and may contribute to the potent antihypertensive action of MPC-1304.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Cálcio/metabolismo , Di-Hidropiridinas/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Animais , Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/metabolismo , Di-Hidropiridinas/metabolismo , Hipertensão/tratamento farmacológico , Técnicas In Vitro , Masculino , Contração Muscular/efeitos dos fármacos , Coelhos , Ratos , Ratos Endogâmicos SHR , Estereoisomerismo
13.
Eur J Pharmacol ; 238(2-3): 139-48, 1993 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-7691619

RESUMO

We investigated the vasodilating action of MPC-1304, one of the most potent dihydropyridines causing hypotension, in anesthetized dogs and compared this with its binding properties. After intraarterial injection, MPC-1304 was 3 times less potent than other dihydropyridines (nitrendipine, nifedipine, nicardipine and nisoldipine) in increasing femoral blood flow. After infusion of these drugs, however, MPC-1304 was the most potent in increasing femoral blood flow. The onset and recovery of the effect of MPC-1304 on femoral blood flow were slower than for nifedipine. Higher doses of Bay K 8644 were needed to antagonize the stimulating activity of MPC-1304 than for nifedipine. In a competition assay of [3H]nitrendipine binding, MPC-1304 and its metabolites bound to the dihydropyridine receptor with lower affinity than the other dihydropyridines. The binding affinity of [3H]MPC-1304 was lower than that of [3H]nitrendipine, consistent with the potency of this drug to increase femoral blood flow by bolus injection. The association and dissociation of [3H]MPC-1304 was slower than those of [3H]nitrendipine, which is consistent with the slow onset and long-lasting vasodilating effects of MPC-1304 on femoral blood flow. Moreover, diltiazem reduced a part of [3H]MPC-1304 binding in a competitive manner. In ex vivo binding assays with serum and aorta obtained after oral administration of the drug in spontaneously hypertensive rats, MPC-1304 inhibited [3H]nitrendipine binding to membrane preparations less potently than nifedipine. From these results, we conclude that MPC-1304 is a different type of dihydropyridine possessing the most potent vasodilating action of the representative dihydropyridines tested. Its activity cannot be explained solely by a slow interaction with voltage-dependent Ca2+ channels.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Di-Hidropiridinas/farmacologia , Hemodinâmica/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Éster Metílico do Ácido 3-Piridinacarboxílico, 1,4-Di-Hidro-2,6-Dimetil-5-Nitro-4-(2-(Trifluormetil)fenil)/farmacologia , Animais , Aorta Torácica/metabolismo , Ligação Competitiva , Bloqueadores dos Canais de Cálcio/metabolismo , Canais de Cálcio Tipo L , Di-Hidropiridinas/metabolismo , Cães , Feminino , Técnicas In Vitro , Masculino , Proteínas Musculares/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Wistar , Suínos , Vasodilatadores/administração & dosagem , Vasodilatadores/metabolismo
14.
J Neurol Sci ; 121(1): 32-8, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8133309

RESUMO

The behavior of rats with progressive hydrocephalus was examined to detect early neurological deterioration. Kaolin solution was injected into the cisterna magna of 10 of 17 anesthetized 8-week-old male rats (day 0), and saline in the other 7 rats (control group). Reaction time (RT, sec) and error ratio (ER, %) of unanesthetized rats escaping from electrical stimuli toward a nonstimulated sheet within a box were recorded daily from day 4 until autopsy after 4 weeks. Three rats in the kaolin group died in acute stage. Rats were assigned to either severe (S) (n = 4) or moderate (M) (n = 4) group according to the degree of ventricular dilatation at autopsy. The RTs prolonged and ERs increased in the kaolin group and they reached their minimum values. Values after the minimum RT value on day 12 in the M-group and 22 in the S-group during the chronic stage were compared with those in the controls, which decreased throughout the experiments (P < 0.03). In all animals in the S-group RT was prolonged each day with a linear regression (P < 0.005), although ER was decreased (0.69 > P > 0.23). In 3 rats and in another rat in the M-group RT was prolonged (P < 0.04 and P = 0.19) and ER was decreased in 3 rats (two: P = 0.41; one: P = 0.01) and increased in one (P = 0.55). In conclusion, deteriorated motor function is more important for early diagnosis in progressive hydrocephalus than behavioral symptoms.


Assuntos
Aprendizagem da Esquiva/fisiologia , Hidrocefalia/fisiopatologia , Hidrocefalia/psicologia , Atividade Motora , Animais , Ventrículos Cerebrais/patologia , Hidrocefalia/induzido quimicamente , Caulim , Masculino , Ratos , Ratos Wistar , Tempo de Reação , Análise de Regressão , Análise e Desempenho de Tarefas
15.
Naunyn Schmiedebergs Arch Pharmacol ; 355(1): 119-25, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9007851

RESUMO

Aranidipine, a novel dihydropyridine derivative, gives rise to two active metabolites, M-1(alpha) and M-1(beta), which exhibit hypotensive activity comparable to that of nifedipine. The aim of this study was to examine the recovery phase of the vasodilating effect of M-1(alpha) and of M-1(beta), to determine their binding characteristics and to compare the results with those for aranidipine and other dihydropyridine derivatives. During intra-arterial infusion into the femoral vascular beds of anesthetized dogs, M-1(alpha), M-1(beta), and nifedipine, produced increases in femoral blood flow at doses three times higher than the dose of aranidipine required to produce a comparable effect. The onset and recovery of the effects of the metabolites on femoral blood flow were significantly slower than the onset and recovery of the effect of nifedipine. The inhibitory activities of M-1(alpha) and M-1(beta) towards stimulated 45Ca uptake in isolated guinea pig aorta were less than that of aranidipine. In binding studies, using porcine heart membrane preparations, [3H]M-1(alpha) and [3H]M-1(beta) had larger Kd values than [3H]aranidipine and [3H]nitrendipine, but the maximal binding number for each of them was almost the same. The association and dissociation rate constants for [3H]M-1(alpha) and [3H]M-1(beta) binding, as well as those for [3H]aranidipine binding, were significantly smaller than those for [3H]nitrendipine, corresponding to the recovery of the in vivo vasodilating effects of the metabolites. The dissociation rate constants of these radiolabeled ligands were highly positively correlated with the elimination rate constants of their in vivo vasodilating effects. From these results, we conclude that M-1(alpha) and M-1(beta), although their binding affinities and Ca2+ antagonistic actions are less potent, possess slower kinetic binding properties than many other dihydropyridines and that the slow kinetic interaction of these metabolites with the dihydropyridine receptor may contribute to the long-lasting in vivo vasodilating effect of aranidipine.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Di-Hidropiridinas/farmacologia , Vasodilatadores/farmacologia , Animais , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/metabolismo , Canais de Cálcio/metabolismo , Canais de Cálcio Tipo L , Di-Hidropiridinas/metabolismo , Cães , Feminino , Cobaias , Cinética , Masculino , Nifedipino/farmacologia , Fluxo Sanguíneo Regional/efeitos dos fármacos
16.
J Neurosurg ; 88(3): 529-34, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9488308

RESUMO

OBJECT: The aim of this study was to investigate the mechanism by which malignant glioma cells escape from growth inhibition mediated by transforming growth factor-beta (TGF-beta), a ubiquitous cytokine that inhibits cell proliferation by causing growth arrest in the G1 phase of the cell cycle. METHODS: The authors measured the response of eight malignant glioma cell lines to the growth-inhibiting activity of TGF-beta in vitro and the expression of TGF-beta Types I and II receptors in malignant glioma cells. The effect of TGF-beta on the expression of a p27Kip1 cyclin-dependent kinase inhibitor was also investigated to assess the downstream signal transmission from TGF-beta receptors. All malignant glioma cell lines were insensitive to growth inhibition by TGF-beta1 and TGF-beta2. Analyses of TGF-beta receptors by means of affinity labeling in which 125I-TGF-beta1 was used showed that six glioma lines had both TGF-beta Types I and II receptors on their cell surfaces, whereas two lines had very small amounts of TGF-beta Type I and/or Type II receptors. Northern blot analysis showed that all tumor lines expressed variable levels of messenger RNAs for both TGF-beta Types I and II receptors. Flow cytometric analyses revealed that treatment of malignant glioma cells with TGF-beta1 significantly downregulated the expression of p27Kip1 protein in all malignant glioma cell lines except one. CONCLUSIONS: The authors suggest that most malignant glioma cells express TGF-beta Types I and II receptors, which can transmit some signals downstream and that the loss of response to TGF-beta growth inhibition may not be caused by an abnormality of the TGF-beta receptors.


Assuntos
Proteínas de Ciclo Celular , Resistencia a Medicamentos Antineoplásicos , Glioma/patologia , Inibidores do Crescimento/farmacologia , Receptores de Fatores de Crescimento Transformadores beta/fisiologia , Fator de Crescimento Transformador beta/farmacologia , Proteínas Supressoras de Tumor , Adenocarcinoma/patologia , Marcadores de Afinidade , Northern Blotting , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Inibidor de Quinase Dependente de Ciclina p27 , Quinases Ciclina-Dependentes/antagonistas & inibidores , Regulação para Baixo/efeitos dos fármacos , Inibidores Enzimáticos/análise , Células Epiteliais/citologia , Fibroblastos/citologia , Citometria de Fluxo , Fase G1/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor/genética , Humanos , Radioisótopos do Iodo , Pulmão/citologia , Proteínas Associadas aos Microtúbulos/análise , Proteínas Associadas aos Microtúbulos/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , Compostos Radiofarmacêuticos , Receptores de Fatores de Crescimento Transformadores beta/efeitos dos fármacos , Receptores de Fatores de Crescimento Transformadores beta/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Pele/citologia , Células Tumorais Cultivadas
17.
Life Sci ; 50(5): 375-81, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1732707

RESUMO

MTP-3631 is a novel thiopyranopyrimidine derivative structurally different from any existent hypoglycemic agents. MTP-3631 markedly decreased basal blood glucose and improved glucose intolerance in genetically diabetic C57BL/6J ob/ob mice, which was not affected by tolbutamide. MTP-3631 also caused hypoglycemic effects in normal rats, but no change was observed in plasma insulin level. Unlike buformin, MTP-3631 did not change plasma lactate level in ob/ob mice. These results suggest that the hypoglycemic mechanism of MTP-3631 may be essentially different from those of sulfonylureas and biguanides.


Assuntos
Hipoglicemiantes/farmacologia , Piperazinas/farmacologia , Pirimidinas/farmacologia , Animais , Glicemia/metabolismo , Buformina/farmacologia , Teste de Tolerância a Glucose , Lactatos/sangue , Camundongos , Camundongos Obesos , Ratos , Ratos Endogâmicos , Tolbutamida/farmacologia
18.
Brain Tumor Pathol ; 14(1): 71-4, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9384806

RESUMO

A 26-year-old man with anaplastic glioma in the left frontoparietal lobe survived for 9 years and 9 months after combined therapy, including subtotal resection, postoperative irradiation, and chemotherapy. The tumor recurred and he received immunotherapy using lymphokine-activated killer (LAK) cells. At the last LAK cell infusion, infection of the Ommaya reservoir occurred, but subsided after antibiotics were administered. Follow-up neuroimaging showed no recurrence of the tumor. Review of the surgical specimens found that the original diagnosis of glioblastoma was inconclusive, although the tumor is considered to be a type of anaplastic glioma.


Assuntos
Neoplasias Encefálicas/patologia , Glioma/patologia , Lobo Parietal/patologia , Adulto , Biomarcadores/análise , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Terapia Combinada , Glioma/mortalidade , Glioma/terapia , Humanos , Imuno-Histoquímica , Imunoterapia , Células Matadoras Ativadas por Linfocina/imunologia , Masculino , Lobo Parietal/química , Lobo Parietal/diagnóstico por imagem , Tomografia Computadorizada por Raios X
19.
Steroids ; 65(12): 871-82, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11077085

RESUMO

A series of 6-ester- (3 and 4) and 6-ether- (7 and 8) substituted androst-4-ene-3,17-diones (androstenediones) and their 1,4-diene analogs (5 and 6, and 9 and 10) as well as C6-substituted 4,6-diene and 1,4,6-triene steroids 11 and 12 were synthesized as aromatase inhibitors to gain insight into the structure-activity relationship between various substituents and inhibitory activity. All of the inhibitors synthesized blocked aromatase in a competitive manner. The inhibitory activities of all of the steroids, except for the 6beta-benzoates 4g and 6h and the 6beta-acetate 6a, were fairly effective to very powerful (K(i): 7.0-320 nM). The 6alpha-n-hexanoyloxy- and 6alpha-benzyloxyandrostenediones (3e and 7e) were the most potent inhibitors (K(i): 7.0 nM each). In the series of 4-ene and 1,4-diene steroids, the 6alpha-substituted steroids had higher affinity for the enzyme than the corresponding 6beta-isomers. In the 1,4-diene steroid series, 6beta-substituted steroids 6a, e, g, and 10a, b, e caused a time-dependent inactivation of aromatase, whereas their 6alpha-isomers 5 and 9 essentially did not. The ether-substituted 1,4,6-trienes 12 inactivated the enzyme in a time-dependent manner; in contrast, their 4,6-diene analogs 11 did not. The substrate androstenedione blocked the inactivation, but no significant effect of L-cysteine was observed. Based on molecular modeling with the PM3 method, along with the present inhibition and inactivation results, it is thought that both the steric effects of the 6-substituents as well as the electronic effects of the C-6 oxygen functions play a critical role in the binding of inhibitors to the active site of aromatase.


Assuntos
Androstenodiona/farmacologia , Aromatase/metabolismo , Androstenodiona/análogos & derivados , Androstenodiona/síntese química , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Aromatase/química , Inibidores da Aromatase , Sítios de Ligação , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Ésteres/química , Éteres/química , Humanos , Cinética , Microssomos/enzimologia , Modelos Moleculares , Placenta/enzimologia , Ligação Proteica , Eletricidade Estática , Relação Estrutura-Atividade , Especificidade por Substrato , Fatores de Tempo
20.
Clin Neuropharmacol ; 21(1): 35-40, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9579283

RESUMO

BAM-1110 [(5R,8R,10R)-6-methyl-8-(1,2,4-triazol-l-ylmethyl) ergoline maleate] is a newly synthesized dopamine agonist that produces little anorexic side effects (nausea and vomiting). The current study examines the effects of BAM-1110 on parkinsonian symptoms in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated monkeys, an animal model of Parkinson's disease. First, a significant antiparkinsonian effect of apomorphine hydrochloride (0.3 mg/kg given subcutaneously) was confirmed in these animals. BAM-1110 (0.1, 0.3, and 1 mg/kg subcutaneously) relieved parkinsonian symptoms in a dose-dependent manner. Significant effects were observed at doses of 0.3 and 1 mg/kg and lasted for at least 3 h. BAM-1110, at a dose of 0.3 mg/kg that produced the submaximal antiparkinsonian effect, did not induce significant abnormal behaviors such as hyperactivity and stereotyped behaviors. Significant stereotyped behaviors were observed at 1 mg/kg of BAM-1110. Apomorphine induced hyperactive and stereotyped behaviors in parallel with its antiparkinsonian effect. BAM-1110 appears to be a potentially useful dopamine agonist to treat Parkinson's disease because of its relatively weak drug-induced hyperactive disturbances and anorexic side effects.


Assuntos
1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Antiparkinsonianos/uso terapêutico , Dopaminérgicos , Agonistas de Dopamina/uso terapêutico , Ergolinas/uso terapêutico , Doença de Parkinson Secundária/tratamento farmacológico , Triazóis/uso terapêutico , Animais , Apomorfina/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Macaca fascicularis , Masculino , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/psicologia , Comportamento Estereotipado/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA