Histamine release upon adenosine 5′-monophosphate (AMP) nasal provocation in allergic subjects
- aIstituto Malattie Apparato Respiratorio, Università di Catania, Via Passo Gravina 187, 95125 Catania, Italy, bUniversity Medicine, Southampton General Hospital, University of Southampton, Southampton SO16 6DY, UK
- Dr R Polosa, University Medicine, Level D, Centre Block, Southampton General Hospital, Southampton SO16 6YD, UK.
- Received 24 June 1998
- Revision requested 28 August 1998
- Revised 30 October 1998
- Accepted 25 November 1998
Abstract
BACKGROUND Nasal provocation with adenosine 5′-monophosphate (AMP) elicits nasal symptoms in subjects with rhinitis. Histamine released from mast cells may play a part in AMP induced nasal responses.
METHODS Symptoms of rhinitis were recorded and histamine release in the fluid obtained by nasal lavage after AMP, guanosine 5′-monophosphate (GMP), and placebo instillations was measured in nine subjects with allergic rhinitis and nine non-allergic controls in a double blind, randomised, placebo controlled study.
RESULTS No symptoms or significant increases in histamine were observed after GMP and placebo challenge. Significantly higher levels of histamine were seen in the nasal lavage fluids of allergic subjects following AMP challenge than in non-allergic controls, the median (range) histamine concentration increasing from the baseline value of 1.62 (0.44–6.99) ng/ml to 6.45 (0.81–16.17) ng/ml at three minutes. No increase in histamine levels was seen in the non-allergic subjects in whom the median histamine concentration was 1.13 (0.29–4.25) ng/ml at baseline and 0.97 (0.31–5.89) ng/ml three minutes after AMP challenge.
CONCLUSIONS AMP elicits an immediate rise in histamine levels in the nasal lavage fluid of allergic subjects compared with non-allergic individuals. These findings indicate that the exaggerated nasal response to adenosine may reflect mast cell priming in vivo, thus supporting its application as a potential new marker of allergic inflammation.
