Canis, Martin

[["dc.bibliographiccitation.firstpage","463"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Otolaryngology--head and neck surgery : official journal of American Academy of Otolaryngology-Head and Neck Surgery"],["dc.bibliographiccitation.lastpage","469"],["dc.bibliographiccitation.volume","145"],["dc.contributor.author","Arpornchayanon, Warangkana"],["dc.contributor.author","Canis, Martin"],["dc.contributor.author","Suckfuell, Markus"],["dc.contributor.author","Ihler, Fritz"],["dc.contributor.author","Olzowy, Bernhard"],["dc.contributor.author","Strieth, Sebastian"],["dc.date.accessioned","2019-07-09T11:53:48Z"],["dc.date.available","2019-07-09T11:53:48Z"],["dc.date.issued","2011-09-01"],["dc.description.abstract","OBJECTIVE: Recent findings support the crucial role of microcirculatory disturbance and ischemia for hearing impairment especially after noise-induced hearing loss (NIHL). The aim of this study was to establish an animal model for in vivo analysis of cochlear microcirculation and hearing function after a loud noise to allow precise measurements of both parameters in vivo. STUDY DESIGN: Randomized controlled trial. Setting. Animal study. Subjects and Methods. After assessment of normacusis (0 minutes) using evoked auditory brainstem responses (ABRs), noise (106-dB sound pressure level [SPL]) was applied to both ears in 6 guinea pigs for 30 minutes while unexposed animals served as controls. In vivo fluorescence microscopy of the stria vascularis capillaries was performed after surgical exposure of 1 cochlea. ABR measurements were derived from the contralateral ear. RESULTS: After noise exposure, red blood cell velocity was reduced significantly by 24.3% (120 minutes) and further decreased to 44.5% at the end of the observation (210 minutes) in contrast to stable control measurements. Vessel diameters were not affected in both groups. A gradual decrease of segmental blood flow became significant (38.1%) after 150 minutes compared with controls. Hearing thresholds shifted significantly from 20.0 ± 5.5 dB SPL (0 minutes) to 32.5 ± 4.2 dB SPL (60 minutes) only in animals exposed to loud noise. CONCLUSION: With regard to novel treatments targeting the stria vascularis in NIHL, this standardized model allows us to analyze in detail cochlear microcirculation and hearing function in vivo."],["dc.identifier.doi","10.1177/0194599811407829"],["dc.identifier.fs","586230"],["dc.identifier.pmid","21636842"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/8048"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/60497"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1097-6817"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.subject.mesh","Animals"],["dc.subject.mesh","Auditory Threshold"],["dc.subject.mesh","Cochlea"],["dc.subject.mesh","Disease Models, Animal"],["dc.subject.mesh","Evoked Potentials, Auditory, Brain Stem"],["dc.subject.mesh","Guinea Pigs"],["dc.subject.mesh","Hearing Loss, Noise-Induced"],["dc.subject.mesh","Loudness Perception"],["dc.subject.mesh","Male"],["dc.subject.mesh","Microcirculation"],["dc.subject.mesh","Microscopy, Fluorescence"],["dc.subject.mesh","Noise"],["dc.subject.mesh","Random Allocation"],["dc.subject.mesh","Statistics, Nonparametric"],["dc.title","Modeling the measurements of cochlear microcirculation and hearing function after loud noise."],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","e39086"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","PloS one"],["dc.bibliographiccitation.lastpage","e39086"],["dc.bibliographiccitation.volume","7"],["dc.contributor.author","Ihler, Fritz"],["dc.contributor.author","Bertlich, Mattis"],["dc.contributor.author","Sharaf, Kariem"],["dc.contributor.author","Strieth, Sebastian"],["dc.contributor.author","Strupp, Michael"],["dc.contributor.author","Canis, Martin"],["dc.date.accessioned","2019-07-09T11:53:37Z"],["dc.date.available","2019-07-09T11:53:37Z"],["dc.date.issued","2012-06-20"],["dc.description.abstract","OBJECTIVE: Betahistine is a histamine H(1)-receptor agonist and H(3)-receptor antagonist that is administered to treat Menière's disease. Despite widespread use, its pharmacological mode of action has not been entirely elucidated. This study investigated the effect of betahistine on guinea pigs at dosages corresponding to clinically used doses for cochlear microcirculation. METHODS: Thirty healthy Dunkin-Hartley guinea pigs were randomly assigned to five groups to receive betahistine dihydrochloride in a dose of 1,000 mg/kg b. w. (milligram per kilogram body weight), 0.100 mg/kg b. w., 0.010 mg/kg b. w., 0.001 mg/kg b. w. in NaCl 0.9% or NaCl 0.9% alone as placebo. Cochlear blood flow and mean arterial pressure were continuously monitored by intravital fluorescence microscopy and invasive blood pressure measurements 3 minutes before and 15 minutes after administration of betahistine. RESULTS: When betahistine was administered in a dose of 1.000 mg/kg b. w. cochlear blood flow was increased to a peak value of 1.340 arbitrary units (SD: 0.246; range: 0.933-1.546 arb. units) compared to baseline (p<0.05; Two Way Repeated Measures ANOVA/Bonferroni t-test). The lowest dosage of 0.001 mg/kg b. w. betahistine or NaCl 0.9% had the same effect as placebo. Nonlinear regression revealed that there was a sigmoid correlation between increase in blood flow and dosages. CONCLUSIONS: Betahistine has a dose-dependent effect on the increase of blood flow in cochlear capillaries. The effects of the dosage range of betahistine on cochlear microcirculation corresponded well to clinically used single dosages to treat Menière's disease. Our data suggest that the improved effects of higher doses of betahistine in the treatment of Menière's disease might be due to a corresponding increase of cochlear blood flow."],["dc.format.extent","6"],["dc.identifier.doi","10.1371/journal.pone.0039086"],["dc.identifier.fs","593711"],["dc.identifier.pmid","22745706"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/7743"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/60463"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1932-6203"],["dc.rights","CC BY 2.5"],["dc.rights.uri","https://creativecommons.org/licenses/by/2.5"],["dc.title","Betahistine exerts a dose-dependent effect on cochlear stria vascularis blood flow in Guinea pigs in vivo."],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]