A novel model of intramedullary spinal cord tumors in rats: functional progression and histopathological characterization.


Journal Article

OBJECTIVE: Intramedullary spinal cord tumors are difficult lesions to treat given their recurrence rate and limited treatment options. The absence of an adequate animal model, however, has hindered the development of new treatment paradigms. In this study, we describe the technique for intramedullary injection of two experimental rodent gliomas (9L and F98) and present the methodology for functional and histopathological analysis of tumor progression. METHODS: F344 rats (n = 24) were randomized into three groups. Group 1 (n = 8) received a 5 microl intramedullary injection of Dulbecco's modified Eagle medium, Group 2 received a 5 microl intramedullary injection of 9L gliosarcoma (100,000) cells, and Group 3 received a 5 microl intramedullary injection of F98 glioma (100,000) cells. The animals were anesthetized, a 2 cm incision was made in the dorsal mid-thoracic region, and the spinous process of the T5 vertebrae was removed to expose the intervertebral space. The ligamentum flavum was removed, and an intramedullary injection was made into the spinal cord. The animals were evaluated daily for signs of paralysis using the Basso, Beattie, and Bresnahan scale and sacrificed after the onset of deficits for histopathological analysis. RESULTS: Animals injected with 9L-gliosarcoma had a median onset of hind limb paresis at 12 +/- 2.9 days. Animals injected with F98 glioma had a median onset of hind limb paresis at 19 +/- 3 days. Animals injected with Dulbecco's modified Eagle medium did not show neurological deficits. Hematoxylin-eosin cross sections confirmed the presence of intramedullary 9L and F98 tumor invading the spinal cord. Control animals had no significant histopathological findings. CONCLUSION: Animals injected with 9L or F98 consistently developed hind limb paresis in a reliable and reproducible manner. The progression of neurological deficits is similar to that seen in patients with intramedullary spinal cord tumors. These findings suggest that this model mimics the behavior of intramedullary spinal cord tumors in humans and may be used to examine the efficacy of new treatment options for both low- and high-grade intramedullary tumors.

Full Text

Cited Authors

  • Caplan, J; Pradilla, G; Hdeib, A; Tyler, BM; Legnani, FG; Bagley, CA; Brem, H; Jallo, G

Published Date

  • July 2006

Published In

Volume / Issue

  • 59 / 1

Start / End Page

  • 193 - 200

PubMed ID

  • 16823316

Pubmed Central ID

  • 16823316

Electronic International Standard Serial Number (EISSN)

  • 1524-4040

International Standard Serial Number (ISSN)

  • 0148-396X

Digital Object Identifier (DOI)

  • 10.1227/01.neu.0000219276.44563.da


  • eng