title: Responses of skeletal muscle hypertrophy in Wistar rats to different resistance exercise models.
abstract: This study aimed to compare the effects of three different resistance exercise models on the quadriceps muscle cross-sectional area, as well as on mTOR phosphorylation and other pivotal molecules involved in the upstream regulation of mTOR. Twenty-four male Wistar rats were divided into untrained (control), endurance resistance training, strength resistance training, and hypertrophy resistance training (HRT) groups (n=6). After 12 weeks of training, the red portion of the quadriceps was removed for histological and Western blot analyses. The results showed that the quadriceps weight and cross-sectional areas in the exercised groups were higher than those of the untrained rats. However, the HRT group presented better results than the other two experimental groups. This same pattern was observed for mTOR phosphorylation and for the most pivotal molecules involved in the upstream control of mTOR (increase of PKB, 14-3-3, ERK, p38 MAPK, and 4E-BP1 phosphorylation, and reduction of tuberin, sestrin 2, REDD1, and phospho AMPK). In summary, our study showed that HRT leads to high levels of mTOR phosphorylation as well as of other proteins involved in the upstream regulation of mTOR.
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Health Sciences Unit, University of Extremo Sul Catarinense, Criciúma, SC, Brazil. ctsouza@unesc.net.
authors.forename: T F
authors.initials: TF
authors.lastname: Luciano
authors.forename: S O
authors.initials: SO
authors.lastname: Marques
authors.forename: B L
authors.initials: BL
authors.lastname: Pieri
authors.forename: D R
authors.initials: DR
authors.lastname: de Souza
authors.forename: L V
authors.initials: LV
authors.lastname: Araújo
authors.forename: R T
authors.initials: RT
authors.lastname: Nesi
authors.forename: D L
authors.initials: DL
authors.lastname: Scheffer
authors.forename: V H
authors.initials: VH
authors.lastname: Comin
authors.forename: R A
authors.initials: RA
authors.lastname: Pinho
authors.forename: A P
authors.initials: AP
authors.lastname: Muller
authors.forename: C T
authors.initials: CT
authors.lastname: de Souza
mesh_terms: D000818:Animals; D008297:Male; D053580:Muscle Strength / Q000502:physiology*; D018482:Muscle, Skeletal / Q000033:anatomy & histology* / Q000502:physiology*; D009929:Organ Size / Q000502:physiology; D010805:Physical Conditioning, Animal / Q000379:methods*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D055070:Resistance Training / Q000379:methods*; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism*; D016896:Treatment Outcome
chemical_list: C546845:mTOR protein, rat; D051057:Proto-Oncogene Proteins c-akt; D058570:TOR Serine-Threonine Kinases