Immunocytochemical characteristics of elbow, knee and ankle muscles of the five-toed jerboa (Allactaga elater).
J Anat
; 202(4): 373-86, 2003 Apr.
Article
in En
| MEDLINE
| ID: mdl-12739615
ABSTRACT
Biochemical adaptations of limb myofibres to intensive bipedal hopping were investigated using the five-toed jerboa Allactaga elater as a model in comparison with the rat. Immunofluorescence methods included immunoreactivity to anti-fast and anti-slow MHC and troponin I. There is no specialization of triceps caput mediale for postural function in the minute non-locomotor forelimbs, unlike quadruped mammals. The various elbow extensor heads and the flexor muscles are alike with regard to fibre type population and cross-sectional areas of each type of fibre. The extensor muscle in the elongated hindlimbs of the five-toed jerboa, at both the knee and the ankle joints, differ from each other extensively. One head, made up of an extremely high percentage of type I, fatigue-resistant fibres, is suited to postural function. Two extensor heads at each joint contain a very high percentage of type IIB fibres (having the greatest maximal velocity of contraction) and are able to produce the powerful acceleration needed to trigger the leap. The relative cross-sectional areas of the myofibres are characteristic of hopping locomotion predominance in number of one type of myofibre in a muscle accompanies greater cross-sectional area, which increases muscle efficiency in either postural or accelerative function of the muscle.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Rodentia
/
Adaptation, Physiological
/
Muscle Fibers, Skeletal
/
Motor Activity
Type of study:
Prognostic_studies
Limits:
Animals
Language:
En
Journal:
J Anat
Year:
2003
Document type:
Article
Affiliation country:
Francia