Summary
Strips of circular muscle from the stomach body showed a spontaneous basal tone of
0.34 ± 0.07 g. The tone of the gastric muscle is reduced by quercetin 30 µM (21%) and
quercetin 100 µM (20%). The tonic contraction induced by 1 µM carbachol was decreased by
31% in the presence of 30 µM quercetin and by 44% in the presence of 100 µM quercetin.
Quercetin 30 µM decrease muscle tone incubated with 4 mM tetraethylammonium (TEA) by
30% and that incubated with1 µM of yohimbine by 26%. Flavone 100 µM caused a decrease
in the gastric muscle tone by 25% and reduced the tonic contraction induced by 1 µM
carbachol by 80%. Flavone 30 µM decreased strips tone by 27% and flavones 100 µM
reduced it by 25%. The flavone 30 µM and 100 µM caused a decrease in the tonic contraction
induced by 1 µM carbachol by 50% and 80% respectively. Flavone 30 µM decreased by 25%
the tone of strips incubated with 4 mM TEA, and exerted a significant inhibitory action by
28% on those incubated in the presence of 1µM yohimbine. These results show that both,
quercetin and flavone decrease the tone of gastric rabbit muscles by a mechanism that does
not appear to involve α2-adrenergic receptors and potassium channels.
The methanolic extract of Lavandula stoechas show an inhibitory effect on gastric
emptying and intestinal transit in mice. The administration of the extract 100 mg/kg and 200
mg/kg reduced the rate of gastric emptying by 23% and 34% respectively, and delayed
intestinal transit by 16% and 23% respectively. Atropine injection (1mg/kg) with or without
extract 200 mg/kg delayed gastric emptying. Inhibition of nitric oxide synthase (NOS) with L-
nitro-n-arginine (L-NNA) (20 mg/kg) did not prevent the delaye of gastric emptying induced
by the extract 200 mg/kg, while the blockade of alpha adrenergic receptors with yohimbine
(1mg/kg) and prazosin (1mg/kg) abolished the inhibitory effect of the extract. Similar results
were observed in the intestinal transit, with the exception of the treatment with L-NNA, where
the inhibitory effect of the extract 200 mg/kg was prevented. This results show a delaying
effect of Lavandula stoechas extract on gastric emptying and intestinal transit in mice with a
mechanism that involve cholinergic, adrenergic and nitrergique pathways in intestinal transit,
and cholinergic and adrenergic pathways in gastric emptying.
Key words: muscular contraction, quercetin, flavone, gastrointestinal muscles, Lavandula
stoechas, gastric emptying, intestinal transit.