epidermal-growth-factor and Lacrimal-Apparatus-Diseases

The purpose of this study was to evaluate changes in tear volume, epidermal growth factor (EGF), and histology of the rabbit lacrimal gland after intraglandular application of botulinum toxin.. Ten New Zealand rabbits were separated into 3 groups. Eight rabbits received botulinum toxin injection (2.5 U per 0.1 mL) into the right lacrimal gland and saline injection (0.1 mL) into the left lacrimal gland as a sham control. Two rabbits were untreated to serve as normal controls. Tear volume was measured using cotton thread every 2 weeks, and 4 rabbits were killed after 2 and 4 weeks. The lacrimal glands were surgically excised and sectioned or lysed for gene expression analysis. Epidermal growth factor expression and concentration were evaluated by real-time polymerase chain reaction and enzyme-linked immunosorbent assay; morphometric and histologic analyses were performed.. The rabbits that were killed 2 weeks after the injection showed decreased tear volume and increased EGF expression and concentration, but differences were not statistically significant. The rabbits that were killed 4 weeks after the injection exhibited similar results. When all 8 rabbits were considered, we detected a significant decrease in tear volume and increased EGF expression and concentration (P = 0.012, P = 0.011, and P = 0.012, respectively). The EGF level was not significantly correlated with the tear volume. There were no prominent histologic changes between the glands, and the lumen versus fibrosis ratio in the interlobular ducts showed no statistically significant difference.. The use of botulinum toxin in patients with epiphora is effective, safe, and repeatable because it reduces tear volume and increases the EGF level to prevent corneal damage while causing no histologic changes.

Topics: Acetylcholine Release Inhibitors; Animals; Botulinum Toxins; Corneal Injuries; Elastic Tissue; Enzyme-Linked Immunosorbent Assay; Epidermal Growth Factor; Gene Expression Profiling; Lacrimal Apparatus; Lacrimal Apparatus Diseases; Male; Rabbits; Real-Time Polymerase Chain Reaction; Tears; Time Factors

The concentration of epidermal growth factor (EGF) in tear fluid (TF) was recently shown to decrease with increasing tear fluid flow (TFF). The purpose of the present study was to clarify the effects of ocular surface disease on the TF EGF concentrations. Tear fluid samples (n = 243) were collected from diseased eyes by means of blunted glass capillaries. The time of collection was measured for each sample, and the tear fluid flow in the capillaries (TFFc) was calculated. The concentration of human EGF (hEGF) was determined using a time-resolved immunofluorometric assay (TR-IFMA). For statistical analysis diagnosis-dependent multigrouping was performed and the data of the patient groups were compared to the data for a control group. The control material consisted of 271 TF samples collected from healthy eyes before (n = 59) and after stimulation of reflex tearing (n = 212). It was shown that TF specimens of patients (n = 243) contained significantly (p less than 0.001) less EGF (mean 952 pg/ml) than the TF of healthy control individuals before (n = 59 samples; mean 6589 pg/ml) or after stimulation of reflex tearing (n = 212 samples; mean 2762 pg/ml). The EGF concentration of every patient group was significantly lower than that found in the TF of control individuals both before and during reflex tearing (p less than 0.001). The rate of EGF released with TF during collection did not differ significantly between the various groups of patients or from that released with the TF of normal individuals before induction of reflex tearing.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Corneal Diseases; Epidermal Growth Factor; Fluoroimmunoassay; Humans; Lacrimal Apparatus Diseases; Statistics as Topic; Tears