Lactoferrin Levels in Tears are Increased by the Topical Application of Diadenosine Tetraphosphate

ABSTRACT

Purpose: This study was undertaken to determine the effect of the topical application of diadenosine tetraphosphate on lactoferrin levels in rabbit tears.

Methods: Diadenosine tetraphosphate was topically instilled in a single-dose, tear samples were collected by micropipette and lactoferrin was measured by Enzyme-Linked ImmunoSorbent Assay (ELISA).

Results: The concentration of lactoferrin in rabbit tears was significantly increased 1 h after diadenosine tetraphosphate application, remaining elevated for 3 h more. This effect was blocked by P2 receptors antagonists.

Conclusions: Topical application of diadenosine tetraphosphate stimulates the secretion of lactoferrin in rabbit tears through P2 receptor activation.

KEYWORDS:

• Diadenosine tetraphosphate
• lactoferrin
• purinergic receptors
• tear film

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Funding

This work was supported by grants from Ministerio de Ciencia e Innovación (SAF2013-44416-R) and RETICS (RD12/0034/0003).

Additional information

Funding

This work was supported by grants from Ministerio de Ciencia e Innovación (SAF2013-44416-R) and RETICS (RD12/0034/0003).