Description:
Context: Warionia saharae Benthem ex Benth. & Coss has been widely
used for gastrointestinal problems in Morocco and Algeria.
Aims: To explore the possible mechanism for its use to such ailments in
order to rationalize some of these folkloric uses. We investigated the
aqueous extract of this plant (AqWs) for antispasmodic activity on
isolated rat and rabbit jejunums.
Methods: To investigate the contractile activity of isolated jejunum
preparations of rat and rabbit we had used in vitro techniques. Jejunums
were suspended in tissue baths filled with KHB culture medium (37°C)
and connected to force transducers. AqWs (0.1–3 mg/mL) was used
with or without carbachol (10-6 M), KCl (25 mM), yohimbine (10-5 M),
prazosin (10-5 M), propranolol (10-5 M), hexamethonium (10-4 M),
atropine (10-6 M), methylene blue (10-5 M), L-NAME (10-4 M) and
nifedipine (10-6 M).
Results: AqWs at 0.1–3 mg/mL produced a relaxation on basal rabbit
contractions with an IC50 = 1.55 ± 0.06 mg/mL. This effect was reversible
and was not affected by pretreatment with the inhibitors of ? and ?
adrenergic receptors yohimbine, prazosin and propranolol. The extract
had an antispasmodic activity with an IC50 = 1.25 ± 0.02 mg/mL on rat
jejunum precontracted with KCl rich medium (25 mM). This result
suggests that the extract had a Ca2+ antagonist effect. This was fortified
when pretreatment of the intestine with the extract induced a rightward
shift in the Ca2+ concentration-response curves. AqWs exhibited also
antispasmodic effect on carbachol (10-6 M)-induced contractions of rat
jejunums with an IC50 = 1.53 ± 0.04 mg/mL. The extract at 3 mg/mL on
rat jejunums pre-incubated with hexamethonium (10-4 M), atropine (10-6
M), and methylene blue (10-5 M), then contracted by KCl, decreased the
maximum contraction but not totally like KCL alone without these
inhibitors. For the jejunum pre-incubated with L-NAME (10-4 M), the
spasmolytic effect of AqWs was comparable with KCL.
Conclusions: These results suggest that the myorelaxant and
antispasmodic effects are mediated possibly via Ca2+ antagonist,
anticholinergic, and guanylate cyclase mechanisms but not by
adrenergic and nitric oxide pathway.
URL:
http://103.158.96.210:88/web_repository/uploads/jppres21.1049_9.5.677.pdf
Type:
Journal
Document:
Diploma III Farmasi
Date:
23-06-2024
Author:
Ouafa Amrani