Sex differences in the number and morphometric properties of muscle spindles in the rat medial gastrocnemius muscle

• Autorzy: Gartych M. , Bukowska D. , Mierzejewska-Krzyzowska B. , Celichowski J.
• Języki publikacji: EN

Abstrakty

EN

INTRODUCTION: There are considerable differences in a number and density of muscle spindles in various skeletal muscles. Considerable sex differences in muscle mass and diameter of extrafusal muscle fibres suggest that muscle spindle density in muscles and morphometric properties of spindles: the diameter, the number and diameters of intrafusal muscle fibres are also different in males and females. Similar number of γ‑motoneurons in male and female rats suggest similar number of muscle spindles but their lower density in males. AIM(S): The aim of the study was to check sex differences in the number, the density and morphometric properties of muscle spindles in rat medial gastrocnemius muscle. METHOD(S): Medial gastrocnemius muscles were excised from two male and two female three-month old Wistar rats. Muscles were stored in 4% formalin solution and then cut into 10 and 20 µm slices stained with methylene blue and magenta. The light microscopy (Nikon microscope with camera and NIS Elements program) was used to calculate a number of muscle spindles in the muscle. The morphometric properties of spindles were measured on the equatorial regions. RESULTS: The number of muscle spindles is similar in male (13), in female (13–14) muscles. However, the density of spindles was different: 86–92 in males and 51–57 mg of the muscle mass per one spindle in females. There were also slight differences in a number of intrafusal muscle fibres in one spindle (in males: 4.3; range 3–8 and in females: 4.5; range 2–7). The diameters of intrafusal fibres on the equatorial regions amounted to: 6.7±2.1 µm in males and 6.6±2.6 µm in females. However, it was noticed that diameters of the male muscle spindles are larger than in the female ones: 21.4±7.3 µm and 20.2±5.7 µm, respectively. CONCLUSIONS: The main sex difference concerns density of muscle spindles which is lower in males than in females.

• Wydawca: -
• Czasopismo: Acta Neurobiologiae Experimentalis
• Rocznik: 2017
• Tom: 77
• Numer: Suppl.1
• Opis fizyczny: p.81-82

Twórcy

autor

Gartych M.

• Poznan University of Physical Education, Department of Neurobiology, Poznan, Poland

autor

Bukowska D.

• Poznan University of Physical Education, Department of Neurobiology, Poznan, Poland

autor

Mierzejewska-Krzyzowska B.

• Poznan University of Physical Education, Faculty of Physical Culture in Gorzow Wielkopolski, Department of Biomedical Sciences and Health Sciences, Division of Morphological Sciences, Biology and Health Sciences, Gorzow Wielkopolski, Poland

autor

Celichowski J.

• Poznan University of Physical Education, Department of Neurobiology, Poznan, Poland