Abdominal Muscles/drug effects; Acetylcholine/antagonists & inhibitors; Anaphylaxis/prevention & control; Angiotensin II/antagonists & inhibitors; Animals; Bradykinin/antagonists & inhibitors; Carbachol/antagonists & inhibitors; Epinephrine/antagonists & inhibitors; Female; Guinea Pigs; Histamine H1 Antagonists/pharmacology; Intestines/drug effects; Isoproterenol/antagonists & inhibitors; Male; Muscle Contraction/drug effects; Muscle, Smooth/drug effects; Oxytocin/antagonists & inhibitors; Potassium Chloride/antagonists & inhibitors; Prostaglandin Antagonists; Rabbits; Rats; Seminal Vesicles/drug effects; Serotonin Antagonists; Surface-Active Agents/pharmacology; Uterus/drug effects