Objective:

2

To investigate the effect of hydro-ethanolic extract of

Zataria multiflora

(

Z. multiflora

) on endothelin level

total and differential white blood cells (WBC) count of sensitized guinea pigs.

Methods:

2

Five groups of guinea pigs sensitized to ovalbumin (OA) were given drinking water alone (group S)

drinking water containing three concentrations of

Z. multiflora

(0.2

0.4 and 0.8 mg/mL as groups S+Z1

S+Z2 and S+Z3) and dexamethasone (group S+D)

n

=6 for each group. The endothelin levels as well as total and differential WBC count in blood of sensitized and control guinea pigs were evaluated using enzyme linked immunosorbent assay method

and hemocytometer and Wright-Giemsa's staining of blood sample smear respectively.

Results:

2

Blood endothelin levels

total and most differential WBC count were increased but lymphocytes decreased in sensitized animals compared to controls (all

P

<

0.01). In groups S+D

S+Z2 and S+Z3 endothelin level

total and differential WBC counts were significantly improved compared with group S (

P

<

0.01). Although

all measured parameters in group S+Z1 was lower than group S+D (

P

<

0.01)

some parameters in group S+Z3 were greater than in group S+D (

P

<

0.05 to

P

<

0.01).

Conclusion:

2

The results showed an anti-inflammatory effect of

Z. multiflora

extract in sensitized guinea pigs

which may suggest a therapeutic potential for the plant on asthma.