Modulation of histamine release from human colon mast cells by protease inhibitors

Table 1 The effects of protease inhibitors on histamine release from human colon mast cells at 15 min incubation period

Compound	Concentration	Net histamine release (%)
ZIGPFM	0.001 μmol/mL	-0.9 ± 0.8
	0.01 μmol/mL	0 ± 1.1
	0.1 μmol/mL	0.8 ± 0.6
	1.0 μmol/mL	0.2 ± 1.2
TPCK	0.08 μmol/mL	3.1 ± 2.0
	0.8 μmol/mL	2.1 ± 1.0
	8.0 μmol/mL	2.0 ± 1.2
	80 μmol/mL	0.7 ± 1.1
α1-antitrypsin	1.0 μmol/mL	0.9 ± 0.5
	10 μmol/mL	1.1 ± 0.6
	30 μmol/mL	1.5 ± 0.6
Lactoferrin	1.0 μmol/mL	-1.0 ± 0.8
	10 μmol/mL	0.8 ± 0.6
	30 μmol/mL	0.5 ± 1.0
TLCK	0.1 μmol/mL	1.7 ± 2.1
	1.0 μmol/mL	1.1 ± 0.6
	10 μmol/mL	2.7 ± 1.7
	100 μmol/mL	3.5 ± 1.2
Amastatin	0.1 μmol/mL	1.5 ± 0.4
	1.0 μmol/mL	2.3 ± 0.6
	10 μmol/mL	3.9 ± 0.6
Leupeptin	2.0 μmol /mL	1.2 ± 0.7
	20 μmol /mL	2.0 ± 1.4
	60 μmol /mL	0.6 ± 0.5
	200 μmol /mL	4.7 ± 0.8a
Protamine	0.1 μg/mL	1.7 ± 1.3
	1.0 μg/mL	1.9 ± 1.4
	10 μg/mL	0.2 ± 2.1
	100 μg/mL	4.5 ± 0.5a
Anti-IgE	10 μg/mL	11 ± 2.7a
Calcium ionophone	1.0 μg/mL	18 ± 3.6a

The values shown are mean ± SEM for four to six separate experiments. Cells were incubated with each concentration of the compound for 15 min at 37 °C. Spontaneous histamine re-lease from these cells was 9.2% ± 1.3%.

^aP < 0.05 compared with buffer alone control (Student’s t test).

Table 2 The effects of protease inhibitors on histamine release from human colon mast cells at 35 min incubation period

Compound	Concentration	Net histamine release (%)
ZIGPFM	0.001 μmol/mL	0.3 ± 0.3
	0.01 μmol/mL	1.0 ± 0.8
	0.1 μmol/mL	1.8 ± 1.3
	1.0 μmol/mL	1.9 ± 0.6
TPCK	0.8 μmol/mL	0.9 ± 2.1
	8.0 μmol/mL	1.8 ± 1.3
	80 μmol/mL	1.7 ± 3.6
TLCK	1.0 μmol/mL	0 ± 2.4
	10 μmol/mL	0.7 ± 1.9
	100 μmol/mL	0.7 ± 2.2
Amastatin	0.1 μmol/mL	1.0 ± 1.7
	1.0 μmol/mL	-1.9 ± 3.3
	10 μmol/mL	0 ± 3.6
Leupeptin	2.0 μmol/mL	1.0 ± 0.7
	20 μmol/mL	1.2 ± 0.7
	60 μmol/mL	0 ± 0.7
	200 μmol/mL	5.1 ± 0.5a
Protamine	1.0 μg/mL	1.2 ± 2.9
	10 μg/mL	1.0 ± 2.5
Anti-IgE	10 μg/mL	10.1 ± 2.5a
Calcium ionophone	1.0 μg/mL	21.8 ± 3.8a

The values shown are mean ± SEM for four to six separate experiments. Spontaneous histamine release from these cells was 9.8% ± 1.7%.

^aP < 0.05 compared with buffer alone control (Student’s t test).