Biomedical subjects
Publications and source records attributed to H Bisgaard.
The effect of leukotriene D4 (LTD4) on lung function was investigated in a controlled study on four normal subjects. A pronounced decrease in airflow was found after inhalation of less than 0.5 nmol, and was most pronounced in the variables generally accepted as indicators of the function of the small airways. No subjective symptoms were experienced.
Using a laser-Doppler-flowmeter the microvascular response to LTC4 and LTD4 was measured. Intradermal injection of 1 microgram LTC4 and LTD4 caused an increase in the microvascular cutaneous bloodflow. The increase in flow was equal to that caused by histamine in equimolar amounts. Blocking the triple-response did not change the response. The values measured after injection of histamine and leucotrienes were about 10-15 times the values found in undisturbed skin and represents probably a maximally dilated vascular bed. Injection of the leucotrienes caused a slight sensation of pain.
An improved skin chamber technique has been devised and used for quantitative evaluation of the leukocyte mobilization rate (LMR). The method was applied in 10 nickel-hypersensitive patients exposed to nickel sulphate. Each patient served as his own control and for additional control purpose, 5 healthy individuals without nickel hypersensitivity were studied. The kinetics of the mobilized leukocytes were followed over a 48-hour period. After an initial lag phase of 2-4 hours, maximum migration was observed from the 24th to the 48th hour, with a wide interindividual variability in the number of mobilized cells at the time of maximum LMR response. The median cumulative leukocyte count was 1.412 x 10(6) leukocytes/cm2/48 h. In the same period a statistically significant increase in the basophils for all the nickel allergic patients was observed. In 8 out of 10 patients a statistically significant effect upon the lymphocytes could be demonstrated. Six of these 8 patients had an increased lymphocyte mobilization. Throughout the period the neutrophil granulocytes were the dominant cell type, although the number decreased as the number of basophils and lymphocytes increased. The chamber technique is a valuable means for quantitative evaluation of leukocyte mobilization and morphology in skin exudates during exposure to an allergen in delayed hypersensitivity reactions.