Title
Activational action of testosterone on androgen receptors protects males preventing temporomandibular joint pain
Date Issued
01 January 2017
Access level
metadata only access
Resource Type
journal article
Author(s)
University of Campinas - UNICAMP
Publisher(s)
Elsevier Inc.
Abstract
Background Testosterone protects male rats from Temporomandibular Joint (TMJ) pain. This study investigated whether this protective effect is mediated by an organizational action of testosterone during nervous system development, by central estrogen and androgen receptors and by the 5α-reduced metabolite of testosterone, dihydrotestosterone. Methods A pharmacological approach was used to assess the ability of the androgen receptor antagonist flutamide, the estrogen receptor antagonist ICI 182 780 and the 5-α reductase inhibitor dutasteride to block the protective effect of testosterone, evaluated through the behavioral response induced by a TMJ injection of 0.5% formalin. Flutamide and ICI 182 780 were injected into the medullary subarachnoid space, and dutasteride and testosterone were systemically administered. Results The TMJ injection of 0.5% formalin induced a significant nociceptive behavioral response in gonadectomized male and naïve female, but not in sham gonadectomized male rats, confirming that endogenous testosterone prevents TMJ nociception in males. Testosterone administration prevented formalin-induced TMJ nociception in males gonadectomized either in the neonatal (at the day of birth) or adult period and in naïve female rats, suggesting that the protective effect of testosterone on TMJ nociception does not depend on its organizational actions during critical periods of development. The administration of flutamide and dutasteride but not of ICI 182 780 blocked the protective effect of testosterone. Conclusions We conclude that the protective effect of testosterone on TMJ nociception depends on activational actions of dihydrotestosterone on androgen receptors rather than on organizational androgenic actions during central nervous system development or estrogenic actions.
Start page
30
End page
35
Volume
152
Language
English
OCDE Knowledge area
Odontología, Cirugía oral, Medicina oral
Endocrinología, Metabolismo (incluyendo diabetes, hormonas)
Subjects
Scopus EID
2-s2.0-84999791821
PubMed ID
Source
Pharmacology Biochemistry and Behavior
ISSN of the container
00913057
Sponsor(s)
We thank Carlos Alberto Feliciano for technical assistance. We thank Carlos Alberto Feliciano for excellent technical assistance. This work was supported by grants from São Paulo Research Foundation (Grant # 2007/57517-4 ).
Sources of information:
Directorio de Producción Científica
Scopus