Signaling Pathways of Purinergic Receptors and Their Interactions with Cholinergic and Adrenergic Pathways in the Lacrimal Gland.

PURPOSE

Purinergic receptors play a key role in the function of the lacrimal gland (LG) as P1 purinergic receptors A, A, and A, P2X receptors, and many of the P2Y receptors are expressed.

METHODS

This review examines the current knowledge of purinergic receptors in the LG as well as the signaling pathways activated by these receptors.

RESULTS

These receptors are expressed on the acinar, ductal, and myoepithelial cells. Considerable crosstalk exists between the pathways activated by P2X receptors with those activated by M muscarinic or α adrenergic receptors. The mechanism of the crosstalk between P2X and M muscarinic receptors differs from that of the crosstalk between P2X and α adrenergic receptors.

CONCLUSIONS

Understanding purinergic receptors and how they modulate protein secretion could play a key role in normal and pathological responses of the LG.