Acetylcholine and prostaglandins

Small doses of garlic are purported to increase the tone of smooth muscle in the gastrointestinal tract, while large doses decrease such actions (Tyler, 1993). An ethanol—chloroform extract of fresh bulb antagonized acetylcholine and prostaglandin E induced rat fundus smooth muscle contraction at a concentration of 0.002 mg/mL however, an ethanol extract of fresh garlic bulb caused rat fundus smooth muscle stimulation at a concentration of 0.016 mg/mL (Ross, 1998). 

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