Smooth muscle contraction induced by Indigofera dendroides leaf extracts may involve calcium mobilization via potential sensitive channels

Abstract

The contractile effects of the aqueous extract of the leaves of Indigofera dendroides (ID) were studied on the gastrointestinal motility in mice and isolated smooth muscle preparations obtained from rats and guinea pigs. The contractile effects of 10(-6) M acetylcholine, 80 mM KCl and 1.6 mg/ml ID were measured on the rat ileal smooth muscle exposed to calcium-free buffer or physiological solution, to determine the calcium pools mobilized by extract for activation of contraction. Acute toxicity test (LD(50)) was also carried out in mice. The result showed that ID (0.05-3.2 mg/ml) produced a concentration-dependent contraction of the guinea pig and rat ileum. These responses were not blocked by mepyramine (2.49 x 10(-9) M), verapamil (8.14 x 10(-9) M), or pirenzepine (4.7 x 10(-7) M), but were blocked completely by atropine (2.92 x 10(-9) M). A significant increase in propulsion of gastrointestinal motility was observed. Acetylcholine, KCl and ID produced contractions in Ca(2+) free media. The phasic components of the contractile responses to Ach as well as the tonic component of K(+) and ID-induced contractions were relatively resistant to short periods of calcium-free exposure. Ach, K(+) and ID still caused contractions in the presence of verapamil. The data revealed that ID-induced contractions were not mediated by histaminergic receptors, calcium channels, M1 muscarinic receptors. It also suggests that Ach mobilize Ca from some tightly bound or intracellular pool, whereas high K(+) and ID may mobilize Ca from some superficial or loosely-bound pool.

Preliminary Phytochemical Screening and Gastrointestinal Study on the Leaf Extract of Stachytarpheta angustifolia Mill Vahl (Verbenaceae) in Rabbit Jejunum

“…The extracts were found to act through the musculotropic route on the rabbit jejunum. This further confirms its activities via the musculotropic route [21,14]. The active principles presents in the extracts are apparently acting on the tissue through the cholinergic receptors and hence are responsible for the actions on the tissue [23,24].…”

“…The method described by [14] and modified by [20] was adopted. The four adult rabbits obtained were starved overnight prior to the experiment.…”

Microencapsulation enhances the anti-ulcerogenic properties of Entada africana leaf extract

“…The charcoal meal test, allows for comparative evaluation of the degree of inhibition or stimulation of gastrointestinal mobility in laboratory animals (Orisadipe et al, 2001). Vagal stimulation of gastric muscarinic receptors has been confirmed to stimulate gastric motility and secretion (Amos et al, 2003). The inhibition of intestinal transit will promote ulcer healing in the case of an orally administered antiulcer agent, as its absorption is increased.…”

“…The method described by Amos et al (2003) was used in this test. Thirty mice were starved of food overnight but allowed unlimited access to drinking water.…”

Inhibitory effect ofSuaeda asparagoides(Miq.) extract on the motility of rat gastric antrum is mediated by β-adrenoceptor

“…Considering the enormous variety of plant species [6], their potential use as new drug sources has not been completely explored [7,8]. The demand for herbal medicinal products for healthcare is increasing globally [9,10].…”