Radioprotective effect of lidocaine on function and ultrastructure of salivary glands receiving fractionated radiation

Int J Radiat Oncol Biol Phys. 2012 Mar 15;82(4):e623-30. doi: 10.1016/j.ijrobp.2011.09.017. Epub 2012 Jan 13.


Purpose: Radiation-induced xerostomia still represents a common side effect after radiotherapy for head-and-neck malignancies. The aim of the present study was to examine the radioprotective effect of lidocaine hydrochloride during fractionated radiation in an experimental animal model.

Methods and materials: To evaluate the influence of different radiation doses on salivary gland function and the radioprotective effect of lidocaine, rabbits were irradiated with 15, 25, 30, and 35 Gy (equivalent doses in 2-Gy fractions equivalent to 24, 40, 48, and 56 Gy, respectively). Lidocaine hydrochloride (10 and 12 mg/kg) was administered before every radiation fraction in the treatment groups. Salivary gland function was assessed by flow sialometry and sialoscintigraphy, and the morphologic changes were evaluated using transmission electron microscopy.

Results: Functional impairment was first observed after 35 Gy and pretreatment with lidocaine improved radiation tolerance of both parotid and submandibular glands. The use of 12 mg/kg lidocaine was superior and displayed significant radioprotection with regard to flow sialometry and sialoscintigraphy. The ultrastructure was largely preserved after pretreatment with both lidocaine doses.

Conclusions: Lidocaine represents an effective radioprotective agent and a promising approach for clinical application to avoid radiation-induced functional impairment of salivary glands.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dose-Response Relationship, Radiation
  • Female
  • Lidocaine / pharmacology*
  • Microscopy, Electron, Transmission
  • Parotid Gland / diagnostic imaging
  • Parotid Gland / drug effects
  • Parotid Gland / radiation effects
  • Parotid Gland / ultrastructure
  • Rabbits
  • Radiation Tolerance / drug effects
  • Radiation-Protective Agents / pharmacology*
  • Radionuclide Imaging
  • Salivary Glands / diagnostic imaging
  • Salivary Glands / drug effects*
  • Salivary Glands / radiation effects*
  • Salivary Glands / ultrastructure
  • Salivation / drug effects
  • Salivation / physiology
  • Salivation / radiation effects
  • Submandibular Gland / diagnostic imaging
  • Submandibular Gland / drug effects
  • Submandibular Gland / radiation effects
  • Ultrasonography
  • Xerostomia / etiology
  • Xerostomia / prevention & control


  • Radiation-Protective Agents
  • Lidocaine