purpose: to evaluate and compare tear secretion and tear film instability following laser in situ keratomileusis (lasik) and laser assisted subepithelial keratectomy (lasek). methods: in a randomized clinical trial, 30 eyes of 15 patients underwent lasik and 30 eyes of 15 patients underwent lasek to correct myopia. tear secretion and tear film instability were tested preoperatively, 2 and 6 wee...

BACKGROUND Although term and preterm infants have the capacity to secrete tears, the relative contribution of basal and reflex secretion of tears has not been previously assessed together in a prospective study. This information potentially has practical clinical importance. OBJECTIVES To measure basal and reflex tear secretion in preterm (30-37 weeks after conception) and term (38-42 weeks) ...

Protease-activated receptor-2 (PAR-2) plays an extensive role in the regulation of digestive exocrine secretion. The present study examined whether PAR-2-related peptides could modulate tear secretion in rats and analyzed the underlying mechanisms. SLIGRL-NH(2), a PAR-2-activating peptide (PAR-2-AP) derived from mouse/rat PAR-2, when administered i.v. in combination with amastatin, an aminopept...

background: ramadan fasting may alter a variety of physiological parameters which by themselves influence ocular system. here, we review the effects of ramadan fasting on the health and function of the eye. materials and methods: literature records in  pubmed/medline, web of science, embase, google scholar, and iran medex databases as well as proceedings of related meetings  from january 1986 t...

Tears are secreted from the lacrimal gland (LG), a dysfunction in which induces dry eye, resulting in ocular discomfort and visual impairment. Honey bee products are used as a nutritional source in daily life and medicine; however, little is known about their effects on dry eye. The aim of the present study was to investigate the effects of honey bee products on tear secretion capacity in dry e...

We found that the original osmolality of the tear film is regained rapidly subsequent to the installation of hypotonic artificial tears or other nonisotonic solutions. The minor irritation due to nonisotonicity and the increased tear volume both contribute to the increased turnover rate which in turn results in the short half-life (measured in seconds) of these solutions in the eye. Despite the...

Tear secretion is important as it supplies water to the ocular surface and keeps eyes moist. Both the parasympathetic and sympathetic pathways contribute to tear secretion. Although intracellular Ca2+ elevation in the acinar cells of lacrimal glands is a crucial event for tear secretion in both the pathways, the Ca2+ channel, which is responsible for the Ca2+ elevation in the sympathetic pathwa...

Purpose Electrical neurostimulation enhances tear secretion, and can be applied to treatment of dry eye disease. Using a chronic implant, we evaluate the effects of stimulating the anterior ethmoid nerve on the aqueous, lipid, and protein content of secreted tears. Methods Neurostimulators were implanted beneath the nasal mucosa in 13 New Zealand white rabbits. Stimulations (2.3-2.8 mA pulses...

Sea buckthorn (Hippophae rhamnoides)-derived products have traditionally been used as food and medicinal ingredients in Eastern countries. The purpose of this study was to investigate the effect of oral intake of sea buckthorn oil products on tear secretion using a murine dry eye model. Orally administered sea buckthorn pulp oil (not seed oil) restored aqueous tear secretion to its normal value...