Time-dependent observations of secretion marker levels in nasal secretion after histamine and methacholine provocations.

Nasal provocation tests with histamine and methacholine were carried out on 25 healthy men in an effort to assess the dynamic changes of albumin, total IgA, secretory IgA and lactoferrin concentrations in the nasal secretion. The trials were performed with 0.5, 1, and 4 mg of histamine and 8, 16, and 32 mg of methacholine. Each dose of histamine or methacholine was sprayed into the nose every 2nd day, with two days' interval between the two provoking agents. Nasal secretions were collected after saline spraying only, forming the baseline group, after 3, 10 and 15 min of administration of the challenge agent. The baseline levels presented the following values: for albumin 257 +/- 230 microg/ml, secretory IgA 608 +/- 379 microg/ml, total IgA 1025 +/- 423 micog/ml, and lactoferrin 213 +/- 156 microg/ml. The increase in albumin level after nasal provocation, particularly significant after histamine administration (to 3713 +/- 2311 microg/ml), indicates incessant protein plasma leakage from the blood circulation to the nasal secretion. After administration of both provocating agents, there was a significant gradual decrease in secretory IgA level, even below the baseline value. After the 2nd and 3rd doses of methacholine and histamine spray, the concentration of secretory IgA decreased by 2-3 times and was found to be 200-300 microg/ml, respectively. Also, lactoferrin concentration values decreased gradually after the 2nd and 3rd doses of methacholine and histamine to levels close the baseline value. These observations suggest a time- and dose-dependent, non-specific dysfunction of local immunity response after nasal provocations.