Does Achillea millefolium extracts possess prokinetic effects on the bovine abomasum thourgh M3 muscarinic receptors?

Displacement of the abomasum is a common disease of the gastrointestinal tract in dairy cattle. Abomasal displacement has been associated with abomasal hypomotility. Therefore, it is necessary to identify effective therapeutic agents that stimulate abomasal motility in cattle. Yarrow (Achillea millefolium) is traditionally used as a folk remedy for treatment of human gastrointestinal complaints in the northwest of Iran. This study investigated the effects of A. millefolium extracts on abomasal smooth muscle preparations from healthy cattle. The A. millefolium extracts (3 to3000 mg L-1) contracted the isolated of smooth muscle in a concentration-dependent manner, with an effective threshold concentration of 30 mg L-1 (p < 0.05). The strongest contraction by A. millefolium aqueous extracts in a concentration of 3000 mg L-1 was observed and amounted to 124.90 ± 10.80% of the control treatment. This action was unaffected by pretreatment with hexamethonium and indomethacin, but strongly reduced by verapamil, atropine and 4-DAMP. The inhibiting effect of 4-DAMP and atropine suggesting that the effect of A. millefolium extracts is mediated at least partly by M3 muscarinic acetylcholine receptor. The results suggested that A. millefolium has the potential prokinetic effect that may prevent or alleviate dysfunctions of gastrointestinal motility.