Faculty Collaboration Database

Testosterone differentially regulates the regenerative properties of injured hamster facial motoneurons. J Neurosci 1991 Dec;11(12):3898-906

Date

12/01/1991

Pubmed ID

1744696

Pubmed Central ID

PMC6575282

DOI

10.1523/JNEUROSCI.11-12-03898.1991

Scopus ID

2-s2.0-0026322290 (requires institutional sign-in at Scopus site)   123 Citations

Abstract

We have previously demonstrated that systemic administration of testosterone accelerates functional recovery, as measured behaviorally, from facial paralysis induced by facial nerve crush axotomy in gonadectomized adult male hamsters. In this investigation, the hypothesis that testosterone enhances return of motor function by increasing the rate of axonal regeneration following injury was tested using fast axonal transport of radioactively labeled proteins to assess facial nerve regeneration. Adult castrated and intact males, and intact females, were subjected to right facial nerve crush axotomy at the stylomastoid foramen. One-half of the axotomized animals in each group received subcutaneous implants of testosterone, with the remainder of the animals sham implanted. Systemic administration of testosterone resulted in a 26-30% increase in the rate of regeneration of the fastest growing population of axons in the male experimental groups, regardless of whether the animal was castrated or not. This rate increase is similar to that observed in the conditioning lesion paradigm utilized by others. In the females, testosterone had a significant, but less pronounced, effect on the rate of axonal regeneration, which may be due in part to inherent gender-related differences in regenerative properties of facial motoneurons. A surprising finding of this study was that no shortening of the delay of sprout formation by testosterone was observed across the various experimental groups. These data suggest that the mechanism by which gonadal steroids act in the injured nervous system is partly through the differential regulation of the regenerative properties of the injured cell, presumably via hormone receptor-mediated action at the level of the neuronal genome.

Author List

Kujawa KA, Emeric E, Jones KJ

Author

Kathy Kujawa MD Associate Professor in the Neurology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Cricetinae
Dihydrotestosterone
Facial Nerve
Female
Male
Mesocricetus
Motor Neurons
Nerve Regeneration
Orchiectomy
Sex Characteristics
Testosterone