title: Immunohistochemical localization of α2-adrenergic receptors in the neonatal rat cochlea and the vestibular labyrinth.
abstract: The α2-adrenergic receptors (α2-ARs), which mediate physiological responses to noradrenaline and adrenaline, are encoded by three different genes but all are coupled to the Gi/Go subfamily of G proteins. The present study investigated the localization of three subtypes, i.e., α2a-, α2b-, and α2c-ARs, in cochlea and vestibular labyrinth in rat in the early postnatal period by immunohistochemistry. The results showed that α2-ARs were widely distributed in regions, including the organ of Corti, spiral ganglion neurons, stria vascularis, crista ampullaris, Scarpa's ganglion, utricle, and Reissner's membrane. Furthermore, the cellular locations of α2-ARs between different cell subtypes as well as receptor subtypes and different observed time points also had diversity. α2a-AR mainly targeted to nuclei at postnatal ages (P)3. While at P(8), only ganglion neurons maintained this character whereas other cell types expressed α2a-AR mainly in plasma membrane. The α2b- and α2c-ARs exhibited predominantly in plasma membrane. Compared with P(8), α2c-AR was not present at stria vascularis at P(3). Overall, our observations indicated that there was region-specific regulation of α2-ARs development in cochlea and vestibular labyrinth. In addition, the extensive expressions of α2-ARs established a significant foundation for the exploration of the function of α2-ARs in cochlea and vestibular labyrinth.
authors: Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, 250021, People's Republic of China.
authors: Jing
authors: J
authors: Cai
authors: Jianfeng
authors: J
authors: Li
authors: Yanyan
authors: Y
authors: Mao
authors: Xiaohui
authors: X
authors: Bai
authors: Lei
authors: L
authors: Xu
authors: Haibo
authors: H
authors: Wang
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D003051:Cochlea / Q000166:cytology / Q000378:metabolism*; D009474:Neurons / Q000145:classification / Q000378:metabolism; D009928:Organ Specificity; D051381:Rats; D018341:Receptors, Adrenergic, alpha-2 / Q000235:genetics / Q000378:metabolism*; D014725:Vestibular Nerve / Q000166:cytology / Q000378:metabolism; D014722:Vestibule, Labyrinth / Q000166:cytology / Q000378:metabolism*
chemical_list: D018341:Receptors, Adrenergic, alpha-2
references: Neurosci Lett. 2000 Feb 25;280(3):159-62
references: 10675785
references: Neuroscience. 1997 Jan;76(1):261-72
references: 8971776
references: Nature. 2007 Nov 1;450(7166):50-5
references: 17972875
references: J Neurochem. 2007 Oct;103(1):57-66
references: 17645455
references: Neuroscience. 2013 Jan 3;228:23-35
references: 23069749
references: Arch Otolaryngol Head Neck Surg. 1990 Apr;116(4):411-7
references: 1969284
references: Eur Arch Otorhinolaryngol. 1991;248(8):459-64
references: 1662964
references: Acta Otolaryngol. 1974 Mar;77(3):185-97
references: 4819031
references: Science. 1996 Aug 9;273(5276):801-3
references: 8670421
references: Brain Res Mol Brain Res. 1994 Feb;21(3-4):355-8
references: 8170357
references: Eur J Pharmacol. 1999 Dec 3;385(2-3):247-53
references: 10607883
references: Acta Otolaryngol. 1983 Jul-Aug;96(1-2):69-74
references: 6613553
references: Neuroscience. 2002;109(4):819-26
references: 11927164
references: J Biol Chem. 1993 Jan 15;268(2):763-6
references: 7678260
references: Ann Otol Rhinol Laryngol. 1993 May;102(5):378-84
references: 8489169
references: Mol Pharmacol. 1982 Nov;22(3):589-94
references: 6296653
references: Hear Res. 1994 Dec;81(1-2):33-41
references: 7737927
references: Hear Res. 1998 May;119(1-2):113-24
references: 9641324
references: Trends Pharmacol Sci. 1997 Jun;18(6):211-9
references: 9227000
references: Acta Otolaryngol. 1966 May;61(5):423-34
references: 5915897
references: Mol Pharmacol. 1997 May;51(5):711-20
references: 9145909
references: Nat Genet. 2002 Jul;31(3):311-5
references: 12068299
references: Physiol Rev. 1988 Oct;68(4):1083-1128
references: 3054946
references: Acta Otolaryngol Suppl. 1991;481:182-6
references: 1927371
references: J Physiol. 1994 Nov 1;480 ( Pt 3):563-73
references: 7869269
references: Hear Res. 1991 Nov;56(1-2):53-64
references: 1663106
references: Brain Res. 1986 Oct 8;384(2):391-4
references: 3022868
references: Nature. 1999 Nov 11;402(6758):181-4
references: 10647009
references: J Neurosci Res. 2007 Oct;85(13):3000-12
references: 17671986
references: Acta Otolaryngol. 1974 Nov-Dec;78(5-6):345-56
references: 4375401
references: Neuroscience. 2004;123(1):167-78
references: 14667451
references: J Pharmacol Exp Ther. 2000 Apr;293(1):1-7
references: 10734146
references: Pharmacol Ther. 1999 Nov;84(2):193-205
references: 10596906
references: Circ Res. 1991 Aug;69(2):509-18
references: 1860188
references: Hear Res. 2002 Mar;165(1-2):1-9
references: 12031509
references: Science. 1996 Aug 9;273(5276):803-5
references: 8670422
references: J Pharmacol Exp Ther. 1992 Jun;261(3):1050-5
references: 1351095
references: Mol Psychiatry. 1999 Sep;4(5):443-52
references: 10523817
references: J Assoc Res Otolaryngol. 2007 Jun;8(2):205-19
references: 17334850
references: Otol Neurotol. 2004 Jul;25(4):457-64
references: 15241221
references: Arch Otorhinolaryngol. 1979;224(1-2):17-23
references: 314796
references: Acta Otolaryngol. 1989 Mar-Apr;107(3-4):171-81
references: 2564716
references: Eur J Neurosci. 1991;3(12):1338-1342
references: 12106231
references: Pharmacol Rev. 1994 Jun;46(2):121-36
references: 7938162
references: J Assoc Res Otolaryngol. 2009 Sep;10(3):369-82
references: 19277783
references: Hypertension. 1993 Jun;21(6 Pt 1):861-5
references: 7684725
references: Mol Pharmacol. 1997 Dec;52(6):1071-80
references: 9415717