PMID- 28277951
OWN - NLM
STAT- MEDLINE
DCOM- 20170727
LR  - 20180523
IS  - 1537-5293 (Electronic)
IS  - 1522-2152 (Linking)
VI  - 90
IP  - 2
DP  - 2017 Mar/Apr
TI  - Within-Winter Flexibility in Muscle Masses, Myostatin, and Cellular Aerobic 
      Metabolic Intensity in Passerine Birds.
PG  - 210-222
LID - 10.1086/688956 [doi]
AB  - Metabolic rates of passerine birds are flexible traits that vary both seasonally 
      and among and within winters. Seasonal variation in summit metabolic rates 
      (M(sum) = maximum thermoregulatory metabolism) in birds is consistently 
      correlated with changes in pectoralis muscle and heart masses and sometimes with 
      variation in cellular aerobic metabolic intensity, so these traits might also be 
      associated with shorter-term, within-winter variation in metabolic rates. To 
      determine whether these mechanisms are associated with within-winter variation in 
      M(sum), we examined the effects of short-term (ST; 0-7 d), medium-term (MT; 14-30 
      d), and long-term (LT; 30-yr means) temperature variables on pectoralis muscle 
      and heart masses, pectoralis expression of the muscle-growth inhibitor myostatin 
      and its metalloproteinase activators TLL-1 and TLL-2, and pectoralis and heart 
      citrate synthase (CS; an indicator of cellular aerobic metabolic intensity) 
      activities for two temperate-zone resident passerines, house sparrows (Passer 
      domesticus) and dark-eyed juncos (Junco hyemalis). For both species, pectoralis 
      mass residuals were positively correlated with ST temperature variables, 
      suggesting that cold temperatures resulted in increased turnover of pectoralis 
      muscle, but heart mass showed little within-winter variation for either species. 
      Pectoralis mRNA and protein expression of myostatin and the TLLs were only weakly 
      correlated with ST and MT temperature variables, which is largely consistent with 
      trends in muscle masses for both species. Pectoralis and heart CS activities 
      showed weak and variable trends with ST temperature variables in both species, 
      suggesting only minor effects of temperature variation on cellular aerobic 
      metabolic intensity. Thus, neither muscle or heart masses, regulation by the 
      myostatin system, nor cellular aerobic metabolic intensity varied consistently 
      with winter temperature, suggesting that other factors regulate within-winter 
      metabolic variation in these birds.
FAU - Swanson, David L
AU  - Swanson DL
FAU - King, Marisa O
AU  - King MO
FAU - Culver, William 3rd
AU  - Culver W 3rd
FAU - Zhang, Yufeng
AU  - Zhang Y
LA  - eng
PT  - Journal Article
PT  - Research Support, U.S. Gov't, Non-P.H.S.
DEP - 20161017
PL  - United States
TA  - Physiol Biochem Zool
JT  - Physiological and biochemical zoology : PBZ
JID - 100883369
RN  - 0 (Myostatin)
SB  - IM
MH  - Adaptation, Physiological/physiology
MH  - Animals
MH  - Energy Metabolism/*physiology
MH  - Heart/anatomy & histology/physiology
MH  - Muscle, Skeletal/*physiology
MH  - Myostatin/*metabolism
MH  - Organ Size
MH  - Oxygen Consumption/*physiology
MH  - Passeriformes/*physiology
MH  - Seasons
OTO - NOTNLM
OT  - birds
OT  - body composition
OT  - heart
OT  - myostatin
OT  - pectoralis
OT  - phenotypic flexibility
OT  - winter
EDAT- 2017/03/10 06:00
MHDA- 2017/07/28 06:00
CRDT- 2017/03/10 06:00
PHST- 2017/03/10 06:00 [entrez]
PHST- 2017/03/10 06:00 [pubmed]
PHST- 2017/07/28 06:00 [medline]
AID - 10.1086/688956 [doi]
PST - ppublish
SO  - Physiol Biochem Zool. 2017 Mar/Apr;90(2):210-222. doi: 10.1086/688956. Epub 2016 
      Oct 17.