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GEOFFREY BURNSTOCK AN. R. ACAD. NAC. FARM.

is suggested by the multiple physiological effects of ATP in
hypoglossal activity associated with the presence of P2X2, P2X4 and
P2X6 receptor mRNA in nucleus ambiguous and the hypoglossal
nucleus.

The pneumovirus respiratory syncytial virus (RSV) is the most
common cause of lower respiratory tract disease in infants and
children. It has a detrimental inhibitory effect on alveolar clearance,
an effect that appears to be mediated by UTP, perhaps released
by the bronchoalveolar epithelium in response to infection. This
suggests that P2Y2 receptor antagonists may be useful for the
treatment of severe RSV broncheotitis.

Alveolar macrophages play a pivotal role in the development of
chronic lung inflammatory reactions such as idiopathic pulmonary
fibrosis, silicosis, asbestosis, hypersensitivity pneumonitis,
sarcoidosis and myobacterium tuberculosis. P2X7 receptors are
expressed in alveolar macrophages, which upon stimulation activate
the proinflammatory IL-1 to IL-5 cytokine cascade and the formation
of multinucleated giant cells, a hallmark of granulomatous reactions
(15). P2X7 receptors may be a relevant target for therapeutic
intervention in lung hypersensitivity reactions associated with
chronic inflammatory responses.

The need to support the failing lung (acute respiratory distress
syndrome [ARDS]) with mechanical ventilation is potentially
lifesaving, but unfortunately, alveolar overdistension and pulmonary
shear stress may cause lung injury (ventilator-induced lung injury,
VILI), increasing bronchoalveolar lavage leading to lung oedema. It
has been suggested that VILI may involve stretch-associated release
of ATP from neuroepithelial cell bodies (NEBs) and may therefore
be a therapeutic target for this condition.

SPECIAL SENSES

Eye

Purinergic signalling is widespread in the eye and novel
therapeutic strategies being developed for glaucoma, dry eye and
retinal detachment (37).

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