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1.
Acta Otolaryngol ; 136(4): 409-13, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26824787

RESUMO

Conclusion These findings suggest that low dose irradiation with 310 nm NB-UVB specifically suppressed the up-regulation of H1R gene expression without inducing apoptosis and that UVB of shorter or longer wavelength than 310 nm NB-UVB had no such effects. Objective To develop a narrowband-ultraviolet B(NB-UVB) phototherapy for allergic rhinitis, this study investigated the effects of irradiation with NB-UVB at wavelength of 310 nm on phorbol-12-myristate-13-acetate (PMA)-induced up-regulation of histamine H1 receptor (H1R) mRNA in HeLa cells. Methods The mRNA levels of H1R in HeLa cells were measured using real-time RT-PCR. Apoptosis were evaluated with DNA fragmentation assay. Results PMA induced a significant increase in H1R mRNA expression in HeLa cells. Irradiation with 305 nm UVB and 310 nm NB-UVB, but not with 315 nm UVB at doses of 200 and 300 mJ/cm(2) significantly suppressed PMA-induced up-regulation of H1R mRNA. At a dose of 200 mJ/cm(2), irradiation with 305 nm UVB, but not with 310 nm NB-UVB, induced apoptosis, although exposure of the cells to both 305 and 310 nm UVB induced apoptosis at a dose of 300 mJ/cm(2) after PMA treatment in HeLa cells. Conversely, irradiation with 315 nm UVB at doses of 200 and 300 mJ/cm(2) did not induce apoptosis.


Assuntos
Células Epiteliais/efeitos da radiação , Receptores Histamínicos H1/metabolismo , Rinite Alérgica/radioterapia , Terapia Ultravioleta , Células Epiteliais/metabolismo , Células HeLa , Humanos , Ésteres de Forbol
2.
Hum Psychopharmacol ; 26(2): 133-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21433074

RESUMO

AIMS: We have evaluated the sedative properties of H1-antihistamines by using positron emission tomography (PET) and ¹¹C-doxepin. The purpose of the present study was to measure histamine H1 receptor occupancy (H1RO) of loratadine 10 mg in patients with allergic rhinitis and to compare this occupancy with that of d-chlorpheniramine 2 mg, a first-generation antihistamine. We also compared our PET findings with the proportional impairment ratio reported by McDonald et al. METHODS: The H1RO of loratadine 10 mg and d-chlorpheniramine 2 mg were evaluated in human brains in a double-blind and crossover design using ¹¹C-doxepin PET. Eleven young male patients with allergic rhinitis were examined by PET following oral single administration of loratadine 10 mg and d-chlorpheniramine 2 mg. RESULTS: Loratadine 10 mg occupied 11.7 ± 19.5% of histamine H1 receptors in the cortex, whereas d-chlorpheniramine 2 mg occupied 53.0 ± 33.2% in the same area, suggesting a non-sedating property of loratadine at a dose of 10 mg. The H1RO values of loratadine and d-chlorpheniramine as well as those of previous studies were found to be significantly proportional to the proportional impairment ratio (r = 0.899). CONCLUSION: Measurement of H1RO is a sensitive and absolute method to characterize the non-sedating property of drugs with H1 antagonistic activity.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Loratadina/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Receptores Histamínicos H1/metabolismo , Adulto , Estudos Cross-Over , Método Duplo-Cego , Antagonistas dos Receptores Histamínicos H1/metabolismo , Humanos , Masculino , Ligação Proteica/fisiologia , Adulto Jovem
3.
J Nucl Med ; 50(6): 887-92, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19443589

RESUMO

UNLABELLED: Some antihistamine drugs that are used for rhinitis and pollinosis have a sedative effect as they enter the brain and block the H(1) receptor, potentially causing serious accidents. Receptor occupancy has been measured with PET under single-dose administration in humans to classify antihistamines as more sedating or as less sedating (or nonsedating). In this study, the effect of repeated administration of olopatadine, an antihistamine, on the cerebral H(1) receptor was measured with PET. METHODS: A total of 17 young men with rhinitis underwent dynamic brain PET with (11)C-doxepin at baseline, under an initial single dose of 5 mg of olopatadine (acute scan), and under another 5-mg dose after repeated administration of olopatadine at 10 mg/d for 4 wk (chronic scan). The H(1) receptor binding potential was estimated using Logan graphical analysis with cerebellum as reference region input. RESULTS: The acute scan showed a slight decrease in H(1) receptor binding potential across the cerebral cortex (by 15% in the frontal cortex), but the chronic scan showed a marked decrease (by 45% from the acute scan in the frontal cortex). Behavioral data before and after the PET scans did not reveal any sedative effect. CONCLUSION: The results may be interpreted as either intracerebral accumulation of olopatadine or H(1) receptor downregulation due to repeated administration. The study shows feasibility and potential value for PET in evaluating the pharmacologic effect of a drug not only after a single dose but also after repeated administration.


Assuntos
Encéfalo/metabolismo , Radioisótopos de Carbono , Dibenzoxepinas/farmacologia , Doxepina/metabolismo , Antagonistas não Sedativos dos Receptores H1 da Histamina/farmacologia , Tomografia por Emissão de Pósitrons/métodos , Receptores Histamínicos H1/metabolismo , Adulto , Humanos , Masculino , Cloridrato de Olopatadina , Adulto Jovem
4.
Drug Metab Pharmacokinet ; 23(2): 106-14, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18445990

RESUMO

Olopatadine, a new second-generation antihistamine, is widely used in the treatment of allergic disorders. The low levels of histamine H1 receptor occupancy in human brain by olopatadine, which is related to its minimal sedation, suggest its low penetration into the brain. The present study evaluates the impact of P-glycoprotein (P-gp) on brain penetration and plasma concentration of olopatadine. The uptake amount of olopatadine in human P-gp transfected LLC-PK1 cells (LLC-GA5-COL150) was lower than that in LLC-PK1. The uptake of olopatadine in LLC-GA5-COL150 was increased in the same level as that in LLC-PK1 in the presence of cyclosporine A, a P-gp inhibitor. After intravenous or oral administration of olopatadine to wild type (WT) and mdr1a/1b knockout (KO) mice at a dose of 1 mg/kg, the brain concentration in KO mice was higher than that in WT mice. On the other hand, the plasma concentration of olopatadine after either route of administration was not different between WT and KO mice. These results suggest that olopatadine is a substrate of P-gp, and that P-gp limits the brain penetration but dose not affect the plasma concentration of olopatadine.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Encéfalo/metabolismo , Dibenzoxepinas/farmacocinética , Antagonistas dos Receptores Histamínicos H1/farmacocinética , Animais , Área Sob a Curva , Barreira Hematoencefálica , Células LLC-PK1 , Masculino , Camundongos , Camundongos Knockout , Cloridrato de Olopatadina
5.
Acta Otolaryngol ; 128(1): 78-85, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17851925

RESUMO

CONCLUSION: This study demonstrates that the co-administration of lipopolysaccharide (LPS) and tumor necrosis factor-alpha (TNF-alpha) (LPS/TNF-alpha) can induce the expression of inducible nitric oxide synthase (iNOS), which results in the generation of apoptosis in cultured human nasal microvascular endothelial cells (HNMECs). Since LPS and TNF-alpha have been suggested to play an important role in the pathophysiology of nasal disease, we conclude that microvascular leakage may therefore contribute to the inflammatory process in nasal disease, such as allergic rhinitis and asthma. MATERIALS AND METHODS: The HNMECs were obtained from the inferior turbinate and subsequently cultured. The expression of iNOS induced by both the LPS and TNF-alpha was investigated by fluorescent immunohistochemistry, using confocal laser microscopy. The DNA-binding dye, Hoechist 33342, was also used to analyze the apoptosis in the HNMECs. RESULTS: The fluorescent immunohistochemistory study demonstrated that LPS and TNF-alpha induced the expression of iNOS in HNMECs. LPS/TNF-alpha remarkably augmented the expression of iNOS in HNMECs in comparison to stimulation by either LPS or TNF-alpha alone. LPS/TNF-alpha also induced apoptosis in HNMECs. 1400W, a highly selective inhibitor of iNOS, inhibited both the expression of iNOS and the apoptosis induced by LPS/TNF-alpha.


Assuntos
Apoptose/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Escherichia coli , Lipopolissacarídeos/farmacologia , Mucosa Nasal/irrigação sanguínea , Óxido Nítrico Sintase Tipo II/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Permeabilidade Capilar/efeitos dos fármacos , Células Cultivadas , Indução Enzimática/efeitos dos fármacos , Humanos , Técnicas In Vitro , Microcirculação/efeitos dos fármacos , Microscopia Confocal , Microscopia de Fluorescência , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo
6.
Hear Res ; 230(1-2): 93-104, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17722255

RESUMO

Nitric oxide (NO) production during hyposmotic stimulation in outer hair cells (OHCs) of the guinea pig cochlea was investigated using the NO sensitive dye DAF-2. Simultaneous measurement of the cell length and NO production showed rapid hyposmotic-induced cell swelling to precede NO production in OHCs. Hyposmotic stimulation failed to induce NO production in the Ca2+-free solution. L-NG-nitroarginine methyl ester (L-NAME), a non-specific NO synthase inhibitor and gadolinium, a stretch-activated channel blocker inhibited the hyposmotic stimulation-induced NO production whereas suramin, a P2 receptor antagonist did not. S-nitroso-N-acetylpenicillamine (SNAP), a NO donor inhibited the hyposmotic stimulation-induced increase in the intracellular Ca2+ concentrations ([Ca2+]i) while L-NAME enhanced it. 1H-[1,2,4]oxadiazole[4,3a]quinoxalin-1-one, an inhibitor of guanylate cyclase and KT5823, an inhibitor of cGMP-dependent protein kinase (PKG) mimicked effects of L-NAME on the Ca2+ response. Transient receptor potential vanilloid 4 (TRPV4), an osmo- and mechanosensitive channel was expressed in the OHCs by means of immunohistochemistry. 4alpha-phorbol 12,13-didecanoate, a TRPV4 synthetic activator, induced NO production in OHCs. These results suggest that hyposmotic stimulation can induce NO production by the [Ca2+]i increase, which is presumably mediated by the activation of TRPV4 in OHCs. NO conversely inhibits the Ca2+ response via the NO-cGMP-PKG pathway by a feedback mechanism.


Assuntos
Tamanho Celular , Células Ciliadas Auditivas Externas/metabolismo , Óxido Nítrico/metabolismo , Órgão Espiral/metabolismo , Transdução de Sinais , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Animais , Cálcio/metabolismo , Carbazóis/farmacologia , Tamanho Celular/efeitos dos fármacos , Células Cultivadas , GMP Cíclico/metabolismo , Proteínas Quinases Dependentes de GMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Inibidores Enzimáticos/farmacologia , Gadolínio/farmacologia , Guanilato Ciclase/antagonistas & inibidores , Guanilato Ciclase/metabolismo , Cobaias , Células Ciliadas Auditivas Externas/efeitos dos fármacos , Soluções Hipotônicas , Indóis/farmacologia , Cinética , Potenciais da Membrana , NG-Nitroarginina Metil Éster/farmacologia , Doadores de Óxido Nítrico/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Órgão Espiral/citologia , Órgão Espiral/efeitos dos fármacos , Pressão Osmótica , Ésteres de Forbol/farmacologia , Potássio/metabolismo , Antagonistas do Receptor Purinérgico P2 , Receptores Purinérgicos P2/metabolismo , S-Nitroso-N-Acetilpenicilamina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Cloreto de Sódio/metabolismo , Suramina/farmacologia , Canais de Cátion TRPV/agonistas , Canais de Cátion TRPV/metabolismo
7.
Hear Res ; 227(1-2): 59-70, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17092670

RESUMO

Nitric oxide (NO) production during hyposmotic stimulation in outer hair cells (OHCs) of the guinea pig cochlea was investigated using the NO sensitive dye DAF-2. Simultaneous measurement of the cell length and NO production showed rapid hyposmotic-induced cell swelling to precede NO production in OHCs. Hyposmotic stimulation failed to induce NO production in the Ca(2+)-free solution. L-N(G)-nitroarginine methyl ester (L-NAME), a non-specific NO synthase inhibitor and gadolinium, a stretch-activated channel blocker inhibited the hyposmotic stimulation-induced NO production whereas suramin, a P2 receptor antagonist did not. S-nitroso-N-acetylpenicillamine (SNAP), a NO donor inhibited the hyposmotic stimulation-induced increase in the intracellular Ca(2+) concentrations ([Ca(2+)](i)) while L-NAME enhanced it. 1H-[1,2,4]oxadiazole[4,3a]quinoxalin-1-one, an inhibitor of guanylate cyclase and KT5823, an inhibitor of cGMP-dependent protein kinase (PKG) mimicked effects of L-NAME on the Ca(2+) response. Transient receptor potential vanilloid 4 (TRPV4), an osmo- and mechanosensitive channel was expressed in the OHCs by means of immunohistochemistry. 4alpha-phorbol 12,13-didecanoate, a TRPV4 synthetic activator, induced NO production in OHCs. These results suggest that hyposmotic stimulation can induce NO production by the [Ca(2+)](i) increase, which is presumably mediated by the activation of TRPV4 in OHCs. NO conversely inhibits the Ca(2+) response via the NO-cGMP-PKG pathway by a feedback mechanism.


Assuntos
Cóclea/metabolismo , Células Ciliadas Auditivas Externas/metabolismo , Óxido Nítrico/metabolismo , Transdução de Sinais , Equilíbrio Hidroeletrolítico , Animais , Cálcio/metabolismo , Carbazóis/farmacologia , Tamanho Celular , Células Cultivadas , Cóclea/citologia , Cóclea/efeitos dos fármacos , Proteínas Quinases Dependentes de GMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Inibidores Enzimáticos/farmacologia , Gadolínio/farmacologia , Guanilato Ciclase/metabolismo , Cobaias , Células Ciliadas Auditivas Externas/efeitos dos fármacos , Soluções Hipotônicas/metabolismo , Indóis/farmacologia , Mecanorreceptores/efeitos dos fármacos , Mecanorreceptores/metabolismo , NG-Nitroarginina Metil Éster/farmacologia , Doadores de Óxido Nítrico/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Ésteres de Forbol/farmacologia , Potássio/metabolismo , Inibidores de Proteínas Quinases/farmacologia , S-Nitroso-N-Acetilpenicilamina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Canais de Cátion TRPV/agonistas , Canais de Cátion TRPV/metabolismo , Regulação para Cima , Equilíbrio Hidroeletrolítico/efeitos dos fármacos
8.
Neuroreport ; 17(2): 135-9, 2006 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-16407759

RESUMO

Transient receptor potential vanilloid 4, the Ca2+-permeable cation channel has been proposed as an osmosensitive and a mechanosensitive channel. We investigated functional expression of transient receptor potential vanilloid 4 in inner hair cells, outer hair cells, and spiral ganglion neurons of the mouse cochlea. Transient receptor potential vanilloid 4 mRNA and protein were expressed in inner hair cells, outer hair cells, and spiral ganglion neurons on the basis of the findings of reverse transcriptase-polymerase chain reaction, single-cell reverse transcriptase-polymerase chain reaction, and immunohistochemistry, whereas they were negative in transient receptor potential vanilloid 4-/- mice cochleae. Hypotonic stimulation and 4-alpha-phorbol 12,13-didecanoate, a transient receptor potential vanilloid 4 synthetic activator, increased the intracellular Ca2+ concentrations in wild-type outer hair cells, whereas in transient receptor potential vanilloid 4-/- mice, outer hair cells failed to exhibit a Ca2+ response to both stimulations. In conclusion, transient receptor potential vanilloid 4 may function as an osmosensory and a mechanosensory receptor in the cochlea.


Assuntos
Cóclea/citologia , Cóclea/metabolismo , Regulação da Expressão Gênica/fisiologia , Neurônios/metabolismo , Canais de Cátion TRPV/fisiologia , Animais , Northern Blotting/métodos , Western Blotting/métodos , Cálcio/metabolismo , Quelantes/farmacologia , Interações Medicamentosas , Ácido Egtázico/farmacologia , Regulação da Expressão Gênica/genética , Soluções Hipotônicas/farmacologia , Imuno-Histoquímica/métodos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/efeitos dos fármacos , Forbóis/farmacologia , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Rutênio Vermelho/metabolismo , Canais de Cátion TRPV/deficiência
9.
Acta Otolaryngol ; 125(9): 929-34, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16193584

RESUMO

CONCLUSION: The results of this study indicate that transient receptor potential subfamily 1 (TRPV1) may play a functional role in sensory cell physiology and that TRPV4 may be important for fluid homeostasis in the inner ear. OBJECTIVE: To analyze the expression of TRPV1 and -4 in the normal guinea pig inner ear. MATERIAL AND METHODS: Albino guinea pigs were used. The location of TRPV1 and -4 in the inner ear, i.e. cochlea, vestibular end organs and endolymphatic sac, was investigated by means of immunohistochemistry. RESULTS: Immunohistochemistry revealed the presence of TRPV1 in the hair cells and supporting cells of the organ of Corti, in spiral ganglion cells, sensory cells of the vestibular end organs and vestibular ganglion cells. TRPV4 was found in the hair cells and supporting cells of the organ of Corti, in marginal cells of the stria vascularis, spiral ganglion cells, sensory cells, transitional cells, dark cells in the vestibular end organs, vestibular ganglion cells and epithelial cells of the endolymphatic sac.


Assuntos
Orelha Interna/química , Canais de Potencial de Receptor Transitório/análise , Animais , Cobaias , Células Ciliadas Auditivas/química , Imuno-Histoquímica , Órgão Espiral/química , Estria Vascular/química
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