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Receptors for glucocorticoids in the human inner ear
Receptors for glucocorticoids in the human inner ear KYLE E. RARe, Phi), and LISAM. CURTIS,~, Gainesville, Florida
Glucocorticoid receptors were detected in the human inner ear. The highest concentration of glucocorticoid receptor protein was measured by enzyme-linked immunosorbent assay in the spiral ligament tissues; the lowest concentration of glucocorticoid receptors was measured in the macula of the saccule. The demonstration of the presence of glucocorticoid receptors in human inner ear tissues provides a basis to consider the direct effects of glucocorticoid action on select inner ear cells, rather than assuming a systemic antiinflammatory or immunosuppressive effect during the therapeutic treatment of patients with given inner ear disorders. (Otolaryngol Head Neck Surg 1996;I 15:38-41 .)
C o r t i c o s t e r o i d s have been used for therapeutic management of certain middle ear disorders 13 and inner ear disorders, 41° including idiopathic sudden hearing loss, autoimmune inner ear diseases, and Meniere's disease. Such corticosteroids include prednisone, dexamethasone, and cortisone. Although corticosteroid therapy has been used, little documentation exists as to whether such therapeutic mechanisms directly or indirectly affect t h e inner ear either biochemically or physiologically. Thus, as identified by Nadol and Wilson, H there have been insufficient data to justify the response of the inner ear to the biologic effects of corticosteroids. In fact, postulations of the effect of steroids have been based solely on data gathered in organ systems other than the ear. It is presumed that the corticosteroid effect is primarily through glucocorticoid receptors (GRs); in fact, it is known that the number of GRs in a given tissue determines the biologic responses of that tissue to corticosteroids? 2 GRs have been identified in inner ear tissues of several animal models) 3-17 Specifically, GRs have been found to be more abun-
From the Departments of Anatomyand Cell Biology(Dr. Rarey and Ms. Curtis) and Otolaryngology(Dr. Rarey), College of Medicine, Universityof Florida. Supported by National Institutes of Health grant no. DC00716, Receivedfor publicationMay26, 1995;revisionreceivedAug. 15, 1995; accepted Oct. 15, 1995. Reprint requests: KyleE. Rarey,PhD, P.O. Box 100235, J. Hillis Miller Health Center, Department of Anatomyand Cell Biology,Universityof Florida, Gainesville,FL 32610. Copyright© 1996by the AmericanAcademyof OtolaryngotogyHead and Neck SurgeryFoundation, Inc. 0194-5998/96/$5.00 + 0 23/1169896 38
dant in cochlear tissues than in vestibular tissues. Within cochlear tissues, G R distribution is highest in the spiral ligament, followed by the organ of Corti and the stria vascularis. 15 Despite new knowledge regarding the presence of glucocorticoids in certain animal models that have been used to study human inner ear diseases, there is no indication that GRs are present in human inner ear tissues. Therefore the objectives of this study were to determine whether G R proteins are present in human inner ear tissues and whether the distribution is tissue specific. The presence of such receptors would imply that corticosteroids could act directly on discrete inner ear tissue regions and thereby influence local microhomeostasis. METHODS AND MATERIAL
Tissue processing was done as follows. Paired human temporal bones were procured from the National Disease Research Interchange (Philadelphia, Pa.). The bones were harvested within 8 hours of death from a 76-year-old man who was diagnosed with Parkinson's disease. On removal from the skull base, the temporal bones were immediately frozen at - 8 0 ° C and stored. A complete cochlear sample and an entire vestibular sample were dissected initially from one temporal bone. On demonstration of the enzyme-linked immunosorbent assay (ELISA) results from whole tissue samples, individual tissue samples of the stria vascularis, spiral ligament, organ of Corti region, and vestibular end organs (three crista ampullaris, macular region of utricle, macular region of saccule, nonampullated portions of three semicircular ducts, dark-cell regions of three ampullae, and nonsensory wall [posterior] of utricle) were
Otolaryngology Head and Neck Surgery Volume 115
RAREY a n d CURTIS 39
Number I
1.8 .6
............................................................
1.4 e,-
® CI
iiiiiiiiiiiiiiiii!!!i iiiiiiiiiiiiiiii!i
1.2 1 0.8
•~ 0.6 0 0.4 0.2 0
100
200
300 400 pg peptide
Fig. t. Correlation of GR pepfide concentrations
m
500
600
700
(pg) to OD measurements.
120
L-.
100 tO
80
N
60
:~
40
~
20
8
¢.-
o ID
Gochlear Vestibular Tissue regions
Fig. 2. Comparison of GR in vestibular tissues to that in cochlear tissues.
dissected from the remaining temporal bone. Tissue samples were placed in Tris-buffered saline solution (10 mmol/L Tris, 150 mmol/L NaC1 [pH 7.4]). The tissue samples were processed for ELISA for GR as described previouslyTM with the exclusion of NazMoO 4 and dithiothreitol. These agents were found to be unnecessary for the ELISA. Protein determinations were made with a modified protocol of the Micro BCA Protein Assay Reagent Kit (Pierce, Rockford, I11.). Tissue samples were diluted with ddH20. A 75-~1 aliquot of this diluted tissue sample was incubated with 75 Ixl of the matrix reagent, which was prepared according to the kit, for 60 minutes at 60° C in a humidified chamber. Wells were read in a microtiter plate reader (EL 312e; Biotek Instruments, Winooski, Vt.) at 590 nm and protein values were calculated. ELISA plate
wells were coated with 44 to 175 ng of tissue protein and subsequently blocked with 4% bovine serum albumin. The polyclonal antibody to the GR (7.8 ng/ixl; Affinity BioReagents, Neshanic Station, N.J.), diluted with 4% bovine serum albumin in Trisbuffered saline solution, was incubated overnight at 4° C, and subsequently, the secondary antibody, horseradish peroxidase-labeled goat antirabbit (Zymed, San Franciso, Calif.), was incubated in the wells for 2 hours at 4° C. Concentrations of GR peptide (Affinity BioReagents), diluted to concentrations of 25 to 667 pg, were run in parallel with the experimental tissues as a standard. Optical density (OD) readings of the wells were obtained from a microtiter plate reader. Regression analyses were performed on the data, and corrected OD values were obtained (Fig. 1). The corrected OD values
40
Otolaryngology Head and Neck Surgery July 1996
RAREYand CURTIS
C
E 120 m~ 100 •~ .
80
•9,o
60
~
40
---
20
¢_
8 (1.
o
Tissue regions
Fig. 3. Distribution of GR in individual regions of the cochlear and vestibular tissues. Amount of GR expressed for each tissue region is relative to that of the spiral ligament {SL}. OC, Organ of Corti; SV, stria vascularis; CA, crista ampullaris; MU, macular region of utricle; MS, macular region of saccule; SC, nonampullated portions of semicircular ducts; ADC, ampullar dark cells; NSV,nonsensory wall [posterior] of utricle.
were converted to their corresponding peptide levels for comparison purposes. Percentages were calculated relative to either the peptide level of cochlear tissues for the whole tissue samples, or of spiral ligament tissues for the individual tissue regions. I~ESULTS
GRs were detected in both the cochlear and vestibular tissues (Fig. 2). The highest GR concentration was detected in the cochlear labyrinth. Of the three cochlear tissue samples, spiral ligament tissues contained the highest levels of GR (Fig. 3); GR levels in organ of Corti tissues were intermediate, and the lowest quantity of GR was detected in tissues of the stria vascularis. Levels of GR in the vestibular labyrinth varied in both the sensory and nonsensory regions (Fig. 3). The crista ampullaris had prominent levels of GR, as did the macula of the utricle. The macula of the saccule contained lower levels of GR. Nonsensory tissues of the semicircular ducts also contained high levels of GR; the ampullar dark cells and posterior wall of the utricle contained relatively low levels of GR. DISCUSSION
GRs were measured in both the cochlear and vestibular tissues of the human inner ear. Within the cochlear tissues, GR levels were highest in spiral ligament tissues and lowest in the stria vascularis.
This pattern of GR distribution was similar to that reported for the rat cochlea, although the values of GR were lower in the human tissues. 15 Levels o f GR in the human vestibular tissues varied. For example, the macula of the utriele and the nonsensory regions of the semicircular ducts contained rather high levels of GR compared with other vestibular regions. Also, GR levels in human vestibular tissues were lower compared with the reported corresponding animal data; however, only the rat ampullar dark-cell region and the macula of the utricle were reported previously)5 A plausible explanation for the differences between the reported human GR levels and those of the rat may be the effect of aging on human tissues and/or possible inner ear diseases. Regardless of the levels of GR measured in the human inner ear, the actual presence of GR provides a cellular means by which circulating glucocorticoids can directly affect inner ear physiology. Previous studies have shown that inner ear tissues, as well as GR inner ear receptors, are dynamic in response to the presence or absence of circulating glucocorticoids.1921 With the presence of GR in both sensory and nonsensory tissues, glucocorticoids may affect not only the homeostasis of ions and fluids within the cochlear and vestibular labyrinths but also signal transduction from the neuroepithelial regions of the inner ear. GRs are cytoplasmic; glucocorticoids can diffuse across a cell's membrane and link directly with its
Otolaryngology H e a d a n d N e c k Surgery
Volume t t 5
Number t
receptor complex without the use of a second messenger system. Subsequently, the GR complex enters a cell's nucleus and affects protein synthesis. In a recent study, amplification and suppression of de novo synthesis of certain inner ear proteins were detected after a given administration of dexamethasone. 22 Therefore, although glucocorticoids are given therapeutically on the presumption of their antiinflammatory and immune-suppressant attributes, glucocorticoids also may play a part in monitoring cellular metabolism within the inner ear through regulation of protein synthesis of metabolic enzymes. Future investigations appear warranted to resolve the presence of GR in the human inner ear, as well as the action of glucocortiocids in normal individuals and in individuals with known inner ear metabolic dysfunction. We thank Mrs. Laurie E. Dew for secretarial assistance. REFERENCES
1. Schwartz RH, Puglese J, Schwartz DM. Use of a short course of prednisone for treating middle ear effusion: a double-blind crossover study. Ann Otol Rhinol Laryngol Suppl 1980;89: 296-300. 2. Macknin ML, Jones PK. Oral dexamethasone for treatment of persistent middle ear effusion. Pediatrics 1985;75:329-35. 3. Oppenheimer P. Short-term steroid therapy: treatment of serous otitis media in children. Arch Otolaryngol 1968;88: 138-40. 4. Fearrington SJ, Weider DJ. Sensori-neural hearing loss in acute otitis media due to beta-hemolytic streptococcus successfully treated with penicillin and prednisone. Ear Nose Throat J 1991;70:508-19. 5. Shea JJ. The medical treatment of sudden hearing loss. In: Johnson JT, Blitzer A, Ossofs RH, eds. Instructional courses of the American Academy of Otolaryngology-Head and Neck Surgery. St. Louis: CV Mosby, 1988:219-21. 6. Matsnoka 1, Kurata K, Kazama N, Nakamura T, Sugimaru T, Satoh M. The beginning of Meniere's disease. Acta Otolaryngol (Stockh) Suppl 1991;481:505-9. 7. Morrison AW. Management of sensorineural deafness. London: Butterworth & Co., Ltd., 1975:175-216.
RAREY a n d CURTIS
41
8. Schiff M, Brown M. Hormones and sudden deafness. Laryngoscope 1974;84:1959-81. 9. Wilson WR, Byl FM, Laird N. The efficacy of steroids in the treatment of idiopathic sudden hearing loss. Arch Otolaryngol 1980;106:772-6. 10. Goldman HB. Hypoadrenocortieism and endoerinologie treatment of Meniere's disease. NY State J Med 1962;62: 377-83. 11. Nadol JB, Wilson WR. Treatment of sudden hearing loss is illogical. In: Snow JB, ed. Controversy in otolaryngology. Philadelphia: WB Saunders, 1980:23-32. 12. Baulieu E-E, Mester J. Steroid hormone receptors. In: DeGroot LJ, ed. Endocrinology. Philadelphia: WB Saunders, 1989:16-39. 13. Rarey KE, Luttge WG. Presence of type I and type II/IB receptors for adrenocorticosteroid hormones in the inner ear. Hear Res 1989;41:217-22. 14. ten Cate W-JF, Curtis LM, Small GM, Rarey KE. Localization of glueocorticoid receptors and glucocortieoid receptor mRNAs in the rat cochlea. Laryngoscope 1993;103:865-71. 15. Rarey KE, Curtis LM, ten Cate W-JF. Tissue specific levels of glueocortieoid receptor within the rat inner ear. Hear Res 1993;64:205-10. 16. Pitovski DZ, Dreseher MJ, Drescher DG. Glueoeorticoid (type II) receptors in the inner ear. Abstracts of the 15th Midwinter Research Meeting of the Association for Research in Otolaryngology, Feb. 2-6, 1992, St. Petersburg, Fla. 17. Pitovski DZ, Drescher MJ, Dreseher DG. Glucocorticoid receptors in the mammalian inner ear: RU 28362 binding sites. Hear Res 1994;77:216-20. 18. ten Cate W-JF, Curtis LM, Rarey KE. Immunoehemical detection of glucocorticoid receptors within rat cochlear and vestibular tissues. Hear Res 1992;60:199-204. 19. ten Care W-JE Patterson K, Rarey KE. Ultrastrueture of ampullar dark cells in the absence of circulating adrenocorticosteroid hormones. Acta Otolaryngol (Stoekh) 1990;110: 234-40. 20. Lohuis PJFM, ten Cate W-JF, Patterson K, Rarey KE. Modulation of the rat stria vascularis in the absence of circulating adrenocorticosteroids. Acta Otolaryngol (Stockh) 1990;110: 348-56. 21. Rarey KE, Lohuis PJFM, ten Cate W-JF. Response of the stria vaseularis to eorticosteroids. Laryngoscope 1991;101: 1081-4. 22. Yao XF, Buhi WC, Alvarez IM, Curtis LM, Rarey KE. D e n o v o synthesis of glueocortieoid hormone regulated inner ear in rats. Hear Res 1995;86:183-8.
Glucocorticoid receptors were detected in the human inner ear. The highest concentration of glucocorticoid receptor protein was measured by enzyme-linked immunosorbent assay in the spiral ligament tissues; the lowest concentration of glucocorticoid receptors was measured in the macula of the saccule. The demonstration of the presence of glucocorticoid receptors in human inner ear tissues provides a basis to consider the direct effects of glucocorticoid action on select inner ear cells, rather than assuming a systemic antiinflammatory or immunosuppressive effect during the therapeutic treatment of patients with given inner ear disorders. (Otolaryngol Head Neck Surg 1996;I 15:38-41 .)
C o r t i c o s t e r o i d s have been used for therapeutic management of certain middle ear disorders 13 and inner ear disorders, 41° including idiopathic sudden hearing loss, autoimmune inner ear diseases, and Meniere's disease. Such corticosteroids include prednisone, dexamethasone, and cortisone. Although corticosteroid therapy has been used, little documentation exists as to whether such therapeutic mechanisms directly or indirectly affect t h e inner ear either biochemically or physiologically. Thus, as identified by Nadol and Wilson, H there have been insufficient data to justify the response of the inner ear to the biologic effects of corticosteroids. In fact, postulations of the effect of steroids have been based solely on data gathered in organ systems other than the ear. It is presumed that the corticosteroid effect is primarily through glucocorticoid receptors (GRs); in fact, it is known that the number of GRs in a given tissue determines the biologic responses of that tissue to corticosteroids? 2 GRs have been identified in inner ear tissues of several animal models) 3-17 Specifically, GRs have been found to be more abun-
From the Departments of Anatomyand Cell Biology(Dr. Rarey and Ms. Curtis) and Otolaryngology(Dr. Rarey), College of Medicine, Universityof Florida. Supported by National Institutes of Health grant no. DC00716, Receivedfor publicationMay26, 1995;revisionreceivedAug. 15, 1995; accepted Oct. 15, 1995. Reprint requests: KyleE. Rarey,PhD, P.O. Box 100235, J. Hillis Miller Health Center, Department of Anatomyand Cell Biology,Universityof Florida, Gainesville,FL 32610. Copyright© 1996by the AmericanAcademyof OtolaryngotogyHead and Neck SurgeryFoundation, Inc. 0194-5998/96/$5.00 + 0 23/1169896 38
dant in cochlear tissues than in vestibular tissues. Within cochlear tissues, G R distribution is highest in the spiral ligament, followed by the organ of Corti and the stria vascularis. 15 Despite new knowledge regarding the presence of glucocorticoids in certain animal models that have been used to study human inner ear diseases, there is no indication that GRs are present in human inner ear tissues. Therefore the objectives of this study were to determine whether G R proteins are present in human inner ear tissues and whether the distribution is tissue specific. The presence of such receptors would imply that corticosteroids could act directly on discrete inner ear tissue regions and thereby influence local microhomeostasis. METHODS AND MATERIAL
Tissue processing was done as follows. Paired human temporal bones were procured from the National Disease Research Interchange (Philadelphia, Pa.). The bones were harvested within 8 hours of death from a 76-year-old man who was diagnosed with Parkinson's disease. On removal from the skull base, the temporal bones were immediately frozen at - 8 0 ° C and stored. A complete cochlear sample and an entire vestibular sample were dissected initially from one temporal bone. On demonstration of the enzyme-linked immunosorbent assay (ELISA) results from whole tissue samples, individual tissue samples of the stria vascularis, spiral ligament, organ of Corti region, and vestibular end organs (three crista ampullaris, macular region of utricle, macular region of saccule, nonampullated portions of three semicircular ducts, dark-cell regions of three ampullae, and nonsensory wall [posterior] of utricle) were
Otolaryngology Head and Neck Surgery Volume 115
RAREY a n d CURTIS 39
Number I
1.8 .6
............................................................
1.4 e,-
® CI
iiiiiiiiiiiiiiiii!!!i iiiiiiiiiiiiiiii!i
1.2 1 0.8
•~ 0.6 0 0.4 0.2 0
100
200
300 400 pg peptide
Fig. t. Correlation of GR pepfide concentrations
m
500
600
700
(pg) to OD measurements.
120
L-.
100 tO
80
N
60
:~
40
~
20
8
¢.-
o ID
Gochlear Vestibular Tissue regions
Fig. 2. Comparison of GR in vestibular tissues to that in cochlear tissues.
dissected from the remaining temporal bone. Tissue samples were placed in Tris-buffered saline solution (10 mmol/L Tris, 150 mmol/L NaC1 [pH 7.4]). The tissue samples were processed for ELISA for GR as described previouslyTM with the exclusion of NazMoO 4 and dithiothreitol. These agents were found to be unnecessary for the ELISA. Protein determinations were made with a modified protocol of the Micro BCA Protein Assay Reagent Kit (Pierce, Rockford, I11.). Tissue samples were diluted with ddH20. A 75-~1 aliquot of this diluted tissue sample was incubated with 75 Ixl of the matrix reagent, which was prepared according to the kit, for 60 minutes at 60° C in a humidified chamber. Wells were read in a microtiter plate reader (EL 312e; Biotek Instruments, Winooski, Vt.) at 590 nm and protein values were calculated. ELISA plate
wells were coated with 44 to 175 ng of tissue protein and subsequently blocked with 4% bovine serum albumin. The polyclonal antibody to the GR (7.8 ng/ixl; Affinity BioReagents, Neshanic Station, N.J.), diluted with 4% bovine serum albumin in Trisbuffered saline solution, was incubated overnight at 4° C, and subsequently, the secondary antibody, horseradish peroxidase-labeled goat antirabbit (Zymed, San Franciso, Calif.), was incubated in the wells for 2 hours at 4° C. Concentrations of GR peptide (Affinity BioReagents), diluted to concentrations of 25 to 667 pg, were run in parallel with the experimental tissues as a standard. Optical density (OD) readings of the wells were obtained from a microtiter plate reader. Regression analyses were performed on the data, and corrected OD values were obtained (Fig. 1). The corrected OD values
40
Otolaryngology Head and Neck Surgery July 1996
RAREYand CURTIS
C
E 120 m~ 100 •~ .
80
•9,o
60
~
40
---
20
¢_
8 (1.
o
Tissue regions
Fig. 3. Distribution of GR in individual regions of the cochlear and vestibular tissues. Amount of GR expressed for each tissue region is relative to that of the spiral ligament {SL}. OC, Organ of Corti; SV, stria vascularis; CA, crista ampullaris; MU, macular region of utricle; MS, macular region of saccule; SC, nonampullated portions of semicircular ducts; ADC, ampullar dark cells; NSV,nonsensory wall [posterior] of utricle.
were converted to their corresponding peptide levels for comparison purposes. Percentages were calculated relative to either the peptide level of cochlear tissues for the whole tissue samples, or of spiral ligament tissues for the individual tissue regions. I~ESULTS
GRs were detected in both the cochlear and vestibular tissues (Fig. 2). The highest GR concentration was detected in the cochlear labyrinth. Of the three cochlear tissue samples, spiral ligament tissues contained the highest levels of GR (Fig. 3); GR levels in organ of Corti tissues were intermediate, and the lowest quantity of GR was detected in tissues of the stria vascularis. Levels of GR in the vestibular labyrinth varied in both the sensory and nonsensory regions (Fig. 3). The crista ampullaris had prominent levels of GR, as did the macula of the utricle. The macula of the saccule contained lower levels of GR. Nonsensory tissues of the semicircular ducts also contained high levels of GR; the ampullar dark cells and posterior wall of the utricle contained relatively low levels of GR. DISCUSSION
GRs were measured in both the cochlear and vestibular tissues of the human inner ear. Within the cochlear tissues, GR levels were highest in spiral ligament tissues and lowest in the stria vascularis.
This pattern of GR distribution was similar to that reported for the rat cochlea, although the values of GR were lower in the human tissues. 15 Levels o f GR in the human vestibular tissues varied. For example, the macula of the utriele and the nonsensory regions of the semicircular ducts contained rather high levels of GR compared with other vestibular regions. Also, GR levels in human vestibular tissues were lower compared with the reported corresponding animal data; however, only the rat ampullar dark-cell region and the macula of the utricle were reported previously)5 A plausible explanation for the differences between the reported human GR levels and those of the rat may be the effect of aging on human tissues and/or possible inner ear diseases. Regardless of the levels of GR measured in the human inner ear, the actual presence of GR provides a cellular means by which circulating glucocorticoids can directly affect inner ear physiology. Previous studies have shown that inner ear tissues, as well as GR inner ear receptors, are dynamic in response to the presence or absence of circulating glucocorticoids.1921 With the presence of GR in both sensory and nonsensory tissues, glucocorticoids may affect not only the homeostasis of ions and fluids within the cochlear and vestibular labyrinths but also signal transduction from the neuroepithelial regions of the inner ear. GRs are cytoplasmic; glucocorticoids can diffuse across a cell's membrane and link directly with its
Otolaryngology H e a d a n d N e c k Surgery
Volume t t 5
Number t
receptor complex without the use of a second messenger system. Subsequently, the GR complex enters a cell's nucleus and affects protein synthesis. In a recent study, amplification and suppression of de novo synthesis of certain inner ear proteins were detected after a given administration of dexamethasone. 22 Therefore, although glucocorticoids are given therapeutically on the presumption of their antiinflammatory and immune-suppressant attributes, glucocorticoids also may play a part in monitoring cellular metabolism within the inner ear through regulation of protein synthesis of metabolic enzymes. Future investigations appear warranted to resolve the presence of GR in the human inner ear, as well as the action of glucocortiocids in normal individuals and in individuals with known inner ear metabolic dysfunction. We thank Mrs. Laurie E. Dew for secretarial assistance. REFERENCES
1. Schwartz RH, Puglese J, Schwartz DM. Use of a short course of prednisone for treating middle ear effusion: a double-blind crossover study. Ann Otol Rhinol Laryngol Suppl 1980;89: 296-300. 2. Macknin ML, Jones PK. Oral dexamethasone for treatment of persistent middle ear effusion. Pediatrics 1985;75:329-35. 3. Oppenheimer P. Short-term steroid therapy: treatment of serous otitis media in children. Arch Otolaryngol 1968;88: 138-40. 4. Fearrington SJ, Weider DJ. Sensori-neural hearing loss in acute otitis media due to beta-hemolytic streptococcus successfully treated with penicillin and prednisone. Ear Nose Throat J 1991;70:508-19. 5. Shea JJ. The medical treatment of sudden hearing loss. In: Johnson JT, Blitzer A, Ossofs RH, eds. Instructional courses of the American Academy of Otolaryngology-Head and Neck Surgery. St. Louis: CV Mosby, 1988:219-21. 6. Matsnoka 1, Kurata K, Kazama N, Nakamura T, Sugimaru T, Satoh M. The beginning of Meniere's disease. Acta Otolaryngol (Stockh) Suppl 1991;481:505-9. 7. Morrison AW. Management of sensorineural deafness. London: Butterworth & Co., Ltd., 1975:175-216.
RAREY a n d CURTIS
41
8. Schiff M, Brown M. Hormones and sudden deafness. Laryngoscope 1974;84:1959-81. 9. Wilson WR, Byl FM, Laird N. The efficacy of steroids in the treatment of idiopathic sudden hearing loss. Arch Otolaryngol 1980;106:772-6. 10. Goldman HB. Hypoadrenocortieism and endoerinologie treatment of Meniere's disease. NY State J Med 1962;62: 377-83. 11. Nadol JB, Wilson WR. Treatment of sudden hearing loss is illogical. In: Snow JB, ed. Controversy in otolaryngology. Philadelphia: WB Saunders, 1980:23-32. 12. Baulieu E-E, Mester J. Steroid hormone receptors. In: DeGroot LJ, ed. Endocrinology. Philadelphia: WB Saunders, 1989:16-39. 13. Rarey KE, Luttge WG. Presence of type I and type II/IB receptors for adrenocorticosteroid hormones in the inner ear. Hear Res 1989;41:217-22. 14. ten Cate W-JF, Curtis LM, Small GM, Rarey KE. Localization of glueocorticoid receptors and glucocortieoid receptor mRNAs in the rat cochlea. Laryngoscope 1993;103:865-71. 15. Rarey KE, Curtis LM, ten Cate W-JF. Tissue specific levels of glueocortieoid receptor within the rat inner ear. Hear Res 1993;64:205-10. 16. Pitovski DZ, Dreseher MJ, Drescher DG. Glueoeorticoid (type II) receptors in the inner ear. Abstracts of the 15th Midwinter Research Meeting of the Association for Research in Otolaryngology, Feb. 2-6, 1992, St. Petersburg, Fla. 17. Pitovski DZ, Drescher MJ, Dreseher DG. Glucocorticoid receptors in the mammalian inner ear: RU 28362 binding sites. Hear Res 1994;77:216-20. 18. ten Cate W-JF, Curtis LM, Rarey KE. Immunoehemical detection of glucocorticoid receptors within rat cochlear and vestibular tissues. Hear Res 1992;60:199-204. 19. ten Care W-JE Patterson K, Rarey KE. Ultrastrueture of ampullar dark cells in the absence of circulating adrenocorticosteroid hormones. Acta Otolaryngol (Stoekh) 1990;110: 234-40. 20. Lohuis PJFM, ten Cate W-JF, Patterson K, Rarey KE. Modulation of the rat stria vascularis in the absence of circulating adrenocorticosteroids. Acta Otolaryngol (Stockh) 1990;110: 348-56. 21. Rarey KE, Lohuis PJFM, ten Cate W-JF. Response of the stria vaseularis to eorticosteroids. Laryngoscope 1991;101: 1081-4. 22. Yao XF, Buhi WC, Alvarez IM, Curtis LM, Rarey KE. D e n o v o synthesis of glueocortieoid hormone regulated inner ear in rats. Hear Res 1995;86:183-8.