"Spine" - what is it, definition of the term
The vertebral column, referred to as «Spine», is the central axial structure of vertebrate organisms, consisting of a series of articulated bones called vertebrae that extend from the skull base to the caudal terminus; in rodents such as rats and mice it provides rigidity for body support, protects the spinal cord, and serves as attachment for muscles that enable locomotion and posture control.
Detailed information
The vertebral column of rodents such as rats and mice consists of a series of articulated bones that protect the central nervous system and support body posture. Each segment includes a vertebra, intervertebral disc, and associated musculature, forming a continuous protective tunnel for the spinal cord.
In rats, the column comprises approximately 27 vertebrae: seven cervical, thirteen thoracic, six lumbar, and a single sacral segment fused with the pelvis. The cervical region exhibits pronounced mobility, facilitating head rotation and exploration. Thoracic vertebrae anchor ribs, contributing to respiratory mechanics, while lumbar vertebrae bear the majority of axial load during locomotion.
Mice display a similar arrangement with a slightly reduced count of vertebrae—typically 26 to 27—reflecting their smaller body size. The proportion of lumbar vertebrae remains comparable, ensuring adequate support for rapid, agile movements. The caudal vertebrae extend into a flexible tail, providing balance and communication functions.
Key anatomical features include:
- Intervertebral discs: fibrocartilaginous cushions that absorb shock and permit limited flexion.
- Spinous processes: dorsal projections serving as attachment points for muscles and ligaments.
- Neural foramina: openings allowing spinal nerves to exit the column and innervate peripheral tissues.
Developmentally, the vertebral column originates from somites during embryogenesis. Segmental patterning is regulated by the HOX gene family, establishing distinct cervical, thoracic, and lumbar identities. Disruptions in this genetic cascade can lead to congenital malformations such as vertebral fusion or curvature abnormalities.
Research applications frequently involve manipulation of the rodent vertebral column to model human spinal disorders. Techniques include:
- Induction of lumbar disc degeneration via needle puncture.
- Genetic knockout of extracellular matrix proteins to assess structural integrity.
- Application of biomechanical loading to evaluate stress‑strain responses.
These models provide insight into disease mechanisms, therapeutic efficacy, and regenerative strategies. Imaging modalities—micro‑CT, MRI, and high‑resolution ultrasound—offer non‑invasive visualization of bone architecture and soft‑tissue changes in live specimens.
«The vertebral column provides structural support while safeguarding neural pathways», a principle reiterated across comparative anatomy studies. Understanding the specific morphology and functional adaptations of rat and mouse backbones underpins translational research aimed at addressing spinal pathology in humans.