A Rabbit Dry Eye Model Induced by Subcutaneous Scopolamine

Area of Science:

• Ophthalmology
• Preclinical Research
• Animal Models

Background:

• Dry eye disease (DED) is a prevalent condition affecting millions worldwide.
• Current DED models have limitations in fully recapitulating human disease pathophysiology.
• Developing reliable animal models is crucial for understanding DED mechanisms and testing therapeutics.

Purpose of the Study:

• To establish and characterize a novel dry eye model in New Zealand rabbits.
• To utilize subcutaneous scopolamine hydrobromide (SCOP) injections to induce DED-like symptoms.
• To evaluate the efficacy of SCOP in mimicking key features of human dry eye.

Main Methods:

• New Zealand male rabbits received daily subcutaneous SCOP injections for 14 days; saline served as a control.
• Ocular surface dryness was assessed via tear secretion measurements and corneal fluorescein staining.
• Inflammatory markers (IL-1β, TNF-α) and MUC5AC expression were analyzed using RT-PCR, Western blot, and immunofluorescence.

Main Results:

• SCOP-treated rabbits showed significantly reduced tear secretion and increased corneal staining.
• Elevated mRNA and protein levels of IL-1β and TNF-α were observed in SCOP-treated eyes and lacrimal glands.
• Conjunctival MUC5AC expression decreased, with observed lacrimal gland inflammation and acinar cell atrophy.

Conclusions:

• Repeated subcutaneous SCOP injections effectively induce key clinical and molecular features of dry eye in rabbits.
• This SCOP-induced rabbit model mimics human DED symptoms, offering a valuable tool for research.
• The model demonstrates ocular surface changes and inflammatory responses relevant to human dry eye disease.