An animal model for external ear canal inflammation

Charles G. Wright, Karen S. Pawlowski, Peter S. Roland, William L. Meyerhoff

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Objective: To develop an animal model for testing efficacy of anti- inflammatory drugs designed to treat external ear canal (EAC) disease. Methods: Histological and morphometric methods were used to characterize EAC inflammation produced by topical application of tetradecanoylphorbol acetate (TPA) in mice. The effects of both single and repeated TPA applications were studied. A treatment trial was performed to evaluate the effects of a ciprofloxacin/hydrocortisone suspension on TPA-induced EAC inflammation. In 10 animals, two bilateral applications of TPA were made, spaced 24 hours apart. Immediately after the second TPA application, otic suspension was applied unilaterally four times over a 48-hour period. The contralateral EACs were left untreated to provide TPA-only controls. Results: Twenty-four hours after a single TPA application, EAC skin showed polymorphonuclear (PMN) leukocyte infiltration, vascular dilation, and thickening of the dermis and epidermis. Dermal and epidermal thickening were more pronounced after two TPA applications and PMN leukocyte infiltration remained high 48 hours after a second TPA placement. After treatment with the otic suspension, PMN leukocyte counts were reduced by an average of 76% relative to EACs that received TPA only. There was also statistically significant reduction of dermal swelling and a trend toward reduced epidermal thickness. Vascular dilation was clearly reduced as well. EACs that received four applications of the suspension alone showed no adverse effects compared with those that received saline. Conclusion: TPA-induced inflammation of the mouse EAC provides a suitable model for testing the therapeutic efficacy of anti-inflammatory agents being considered for clinical use.

Original languageEnglish (US)
Pages (from-to)1112-1118
Number of pages7
JournalLaryngoscope
Volume110
Issue number7
StatePublished - Jul 2000

Fingerprint

Otitis
Ear Canal
Tetradecanoylphorbol Acetate
Animal Models
Suspensions
Neutrophils
Skin
Ear
Blood Vessels
Dilatation
Anti-Inflammatory Agents
Ear Diseases
Dermis
Leukocyte Count
Epidermis

Keywords

  • Anti-inflammatory agents
  • Hydrocortisone
  • Mouse
  • Tetradecanoylphorbol acetate

ASJC Scopus subject areas

  • Otorhinolaryngology

Cite this

Wright, C. G., Pawlowski, K. S., Roland, P. S., & Meyerhoff, W. L. (2000). An animal model for external ear canal inflammation. Laryngoscope, 110(7), 1112-1118.

An animal model for external ear canal inflammation. / Wright, Charles G.; Pawlowski, Karen S.; Roland, Peter S.; Meyerhoff, William L.

In: Laryngoscope, Vol. 110, No. 7, 07.2000, p. 1112-1118.

Research output: Contribution to journalArticle

Wright, CG, Pawlowski, KS, Roland, PS & Meyerhoff, WL 2000, 'An animal model for external ear canal inflammation', Laryngoscope, vol. 110, no. 7, pp. 1112-1118.
Wright CG, Pawlowski KS, Roland PS, Meyerhoff WL. An animal model for external ear canal inflammation. Laryngoscope. 2000 Jul;110(7):1112-1118.
Wright, Charles G. ; Pawlowski, Karen S. ; Roland, Peter S. ; Meyerhoff, William L. / An animal model for external ear canal inflammation. In: Laryngoscope. 2000 ; Vol. 110, No. 7. pp. 1112-1118.
@article{59b7984a5d8a4eeaa9b40524e399a386,
title = "An animal model for external ear canal inflammation",
abstract = "Objective: To develop an animal model for testing efficacy of anti- inflammatory drugs designed to treat external ear canal (EAC) disease. Methods: Histological and morphometric methods were used to characterize EAC inflammation produced by topical application of tetradecanoylphorbol acetate (TPA) in mice. The effects of both single and repeated TPA applications were studied. A treatment trial was performed to evaluate the effects of a ciprofloxacin/hydrocortisone suspension on TPA-induced EAC inflammation. In 10 animals, two bilateral applications of TPA were made, spaced 24 hours apart. Immediately after the second TPA application, otic suspension was applied unilaterally four times over a 48-hour period. The contralateral EACs were left untreated to provide TPA-only controls. Results: Twenty-four hours after a single TPA application, EAC skin showed polymorphonuclear (PMN) leukocyte infiltration, vascular dilation, and thickening of the dermis and epidermis. Dermal and epidermal thickening were more pronounced after two TPA applications and PMN leukocyte infiltration remained high 48 hours after a second TPA placement. After treatment with the otic suspension, PMN leukocyte counts were reduced by an average of 76{\%} relative to EACs that received TPA only. There was also statistically significant reduction of dermal swelling and a trend toward reduced epidermal thickness. Vascular dilation was clearly reduced as well. EACs that received four applications of the suspension alone showed no adverse effects compared with those that received saline. Conclusion: TPA-induced inflammation of the mouse EAC provides a suitable model for testing the therapeutic efficacy of anti-inflammatory agents being considered for clinical use.",
keywords = "Anti-inflammatory agents, Hydrocortisone, Mouse, Tetradecanoylphorbol acetate",
author = "Wright, {Charles G.} and Pawlowski, {Karen S.} and Roland, {Peter S.} and Meyerhoff, {William L.}",
year = "2000",
month = "7",
language = "English (US)",
volume = "110",
pages = "1112--1118",
journal = "Laryngoscope",
issn = "0023-852X",
publisher = "John Wiley and Sons Inc.",
number = "7",

}

TY - JOUR

T1 - An animal model for external ear canal inflammation

AU - Wright, Charles G.

AU - Pawlowski, Karen S.

AU - Roland, Peter S.

AU - Meyerhoff, William L.

PY - 2000/7

Y1 - 2000/7

N2 - Objective: To develop an animal model for testing efficacy of anti- inflammatory drugs designed to treat external ear canal (EAC) disease. Methods: Histological and morphometric methods were used to characterize EAC inflammation produced by topical application of tetradecanoylphorbol acetate (TPA) in mice. The effects of both single and repeated TPA applications were studied. A treatment trial was performed to evaluate the effects of a ciprofloxacin/hydrocortisone suspension on TPA-induced EAC inflammation. In 10 animals, two bilateral applications of TPA were made, spaced 24 hours apart. Immediately after the second TPA application, otic suspension was applied unilaterally four times over a 48-hour period. The contralateral EACs were left untreated to provide TPA-only controls. Results: Twenty-four hours after a single TPA application, EAC skin showed polymorphonuclear (PMN) leukocyte infiltration, vascular dilation, and thickening of the dermis and epidermis. Dermal and epidermal thickening were more pronounced after two TPA applications and PMN leukocyte infiltration remained high 48 hours after a second TPA placement. After treatment with the otic suspension, PMN leukocyte counts were reduced by an average of 76% relative to EACs that received TPA only. There was also statistically significant reduction of dermal swelling and a trend toward reduced epidermal thickness. Vascular dilation was clearly reduced as well. EACs that received four applications of the suspension alone showed no adverse effects compared with those that received saline. Conclusion: TPA-induced inflammation of the mouse EAC provides a suitable model for testing the therapeutic efficacy of anti-inflammatory agents being considered for clinical use.

AB - Objective: To develop an animal model for testing efficacy of anti- inflammatory drugs designed to treat external ear canal (EAC) disease. Methods: Histological and morphometric methods were used to characterize EAC inflammation produced by topical application of tetradecanoylphorbol acetate (TPA) in mice. The effects of both single and repeated TPA applications were studied. A treatment trial was performed to evaluate the effects of a ciprofloxacin/hydrocortisone suspension on TPA-induced EAC inflammation. In 10 animals, two bilateral applications of TPA were made, spaced 24 hours apart. Immediately after the second TPA application, otic suspension was applied unilaterally four times over a 48-hour period. The contralateral EACs were left untreated to provide TPA-only controls. Results: Twenty-four hours after a single TPA application, EAC skin showed polymorphonuclear (PMN) leukocyte infiltration, vascular dilation, and thickening of the dermis and epidermis. Dermal and epidermal thickening were more pronounced after two TPA applications and PMN leukocyte infiltration remained high 48 hours after a second TPA placement. After treatment with the otic suspension, PMN leukocyte counts were reduced by an average of 76% relative to EACs that received TPA only. There was also statistically significant reduction of dermal swelling and a trend toward reduced epidermal thickness. Vascular dilation was clearly reduced as well. EACs that received four applications of the suspension alone showed no adverse effects compared with those that received saline. Conclusion: TPA-induced inflammation of the mouse EAC provides a suitable model for testing the therapeutic efficacy of anti-inflammatory agents being considered for clinical use.

KW - Anti-inflammatory agents

KW - Hydrocortisone

KW - Mouse

KW - Tetradecanoylphorbol acetate

UR - http://www.scopus.com/inward/record.url?scp=0033923225&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0033923225&partnerID=8YFLogxK

M3 - Article

C2 - 10892679

AN - SCOPUS:0033923225

VL - 110

SP - 1112

EP - 1118

JO - Laryngoscope

JF - Laryngoscope

SN - 0023-852X

IS - 7

ER -