Korean J Ophthalmol.  2021 Dec;35(6):460-466. 10.3341/kjo.2021.0027.

Thermal Injury Induces Small Heat Shock Protein in the Optic Nerve Head In Vivo

• Kim JM
• Kim YJ
• Park KH

• KMID: 2523039
• DOI: http://doi.org/10.3341/kjo.2021.0027

Abstract

Purpose
To investigate the induction pattern of various heat shock protein (HSP) in the optic nerve head after thermal stress using transpupillary thermotherapy and to determine the dose-response relationship of thermal stress on the induction of various HSP.
Methods
The 810-nm diode laser with 50-μm spot size was aimed to the center of optic nerve head of right eye of Norway brown rats. First, the various exposure powers (100, 120, 140 mW) were used with the same exposure duration, 60 seconds, to investigate power dosing effect. Second, the various exposure durations (1, 2, 3, and 5 minutes) were applied under constant 100 mW laser power to investigate time dosing effect. Left eyes were served as controls. To quantify HSP expression, enucleation was performed at 24 hours after transpupillary thermotherapy. HSP 27 and αB-crystallin inductions in optic nerve head were examined with Western blot.
Results
All type of HSP was observed in normal state. After thermal injury, the expression of HSP 27 were increased, and the αB-crystallin were decreased.
Conclusions
Induction pattern of each HSP in the optic nerve head were different after thermal injury. Some HSPs were induced or exhausted. Further research is needed on the characteristic functions and induction conditions of each HSP.

Keyword

Heat-shock proteins; Lasers; Optic nerve