Determination of prednisolone in the cochlear tissue

Tobita, Tadamichi; Senarita, Masamitsu; Hara, Akira; Kusakari, Jun

doi:10.1016/s0378-5955(01)00394-x

Cited by 33 publications

(24 citation statements)

References 14 publications

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“…In particular, there were in some cases higher intralabyrinthine gentamicin levels than the levels in the serum. The phenomenon of having higher concentrations within the perilymph than in the serum was also observed in our study and could be due to local metabolism including different binding capacities within the inner ear and the blood-perilymph barrier as suggested by Tobita et al [2002].…”

Section: Discussionsupporting

confidence: 80%

“…On the other side, differences in the metabolism of corticosteroids in the inner ear including the binding capacity must be considered. Tobita et al [2002] analysed the uptake and elimination pattern of prednisolone in cochlear tissue, brain, hepatic tissue and in serum. They observed a slower elimination of prednisolone from the cochlear tissue compared to brain, liver and serum.…”

Section: Discussionmentioning

confidence: 99%

“…Erroneous single or multiple application of prednisolone on the morning of surgery was excluded. A possible explanation for the high perilymph and normal serum level could be an excitatory status of the patient since prednisolone clears the serum much faster than the perilymph [Parnes et al, 1999;Tobita et al, 2002]. We analysed the measuring and calculation error of our detection system.…”

Section: Discussionmentioning

confidence: 99%

“…Obviously, it cannot be excluded that a higher cortisol level can be found at an earlier or a later time point. Prednisolone concentration in homogenized cochlear tissue of guinea pigs taken at 0.5, 1, 2, 4 and 8 h after intravenous injection of prednisolone (100 mg/kg) peaked at 1 h and at 0.5 h in serum [Tobita et al, 2002]. In the time period between 0.5 and 1 h, neither tissue nor serum were analysed and the whole cochlea prednisolone concentration was examined and not perilymph in particular.…”

Section: Discussionmentioning

confidence: 99%

“…We assume that the peak value in the perilymph is reached before the peak value in the cochlear tissue. Of note is the high dose of prednisolone used by Tobita et al [2002] (100 mg/kg) and by the high-dose group of Parnes et al [1999] (20 mg/kg) which exceeded the human dose by far. The pharmacokinetic of prednisolone is difficult to determine in the human as firstly a high number of patients is needed to overcome the large interindividual differences and secondly only a minute amount of sample in the microlitre range is available.…”

Section: Discussionmentioning

confidence: 99%

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Cortisol Levels in the Human Perilymph after Intravenous Administration of Prednisolone

Niedermeyer

Zahneisen²,

Luppa³

et al. 2003

Audiol Neurotol

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Cortisone is used in various inner ear disorders such as sudden hearing loss. However, it is not known if the doses of prednisolone employed in therapy increase the cortisol level in the inner ear. To evaluate the level of cortisol within the perilymph after intravenous administration of 125 and 250 mg of prednisolone, serum and perilymph samples of 29 consecutive patients with clinical otosclerosis subjected to stapedectomy were collected. Cortisol levels were determined by RIA. The perilymphatic cortisol level was significantly increased in the group with 250 mg of prednisolone while the perilymphatic cortisol levels were not significantly different between the control group and the patients treated with 125 mg. Although the therapeutic dose of prednisolone is not known, we conclude that the application of 250 mg has a greater impact on the inner ear than 125 mg.

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Section: Discussionsupporting

confidence: 80%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

See 3 more Smart Citations

Cortisol Levels in the Human Perilymph after Intravenous Administration of Prednisolone

Niedermeyer

Zahneisen²,

Luppa³

et al. 2003

Audiol Neurotol

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Reducing scar formation by regulation of IL‐1 and MMP‐9 expression by using sustained release of prednisolone‐loaded PDLL microspheres in a murine wound model

Wu¹,

Hsu²,

Chang³

et al. 2012

J Biomedical Materials Res

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In this study, we provide a new pharmacological treatment, which may prevent scar formation on wound healing and/or plastic surgery wounds. We used prednisolone to reduce scar formation in wound excision. To prolong the drug effect, prednisolone of different amounts were encapsulated in biodegradable poly(D,L-lactide) (PDLL) microspheres. In the in vitro cell healing study, prednisolone was markedly effective in reducing the growth rate of fibroblast cells according to electric cell-substrate impedance sensing results. At a higher density of prednisolone, a slower growth rate was observed (ANOVA, p < 0.05). In rat models of skin wound healing studies, results show that in postsurgery days 7 and 14, all of the wound fibrosis areas administered with 0.5 and 5 mM of prednisolone-loaded PDLL microspheres (PPM) were decreased by 6-116% compared with those of the control groups (ANOVA, p < 0.05). Adding the PPM led to reduce IL-1β but increase MMP-9 expression levels as compared with the control groups (ANOVA, p < 0.0001). These results implies that using sustained releasing prednisolone microspheres can regulate ECM generated from fibroblasts, can avoid excess proliferation and reduce the formation of scar tissue during wound regeneration by inhibiting the degree of inflammation.

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