Organ Response M,M y Sphincter muscle of iris Contraction(miosis) Ciliary muscle Contraction for near vision Heart Sinoatrial node Decrease in rate (negative chronotropy) Atria Decrease in contractile strength (negative inotropy) Decrease in refractory period 不应期 Atrioventricular node Decrease in conduction velocity(negative dro- motropy) Increase in refractory period Ventricles Small decrease in contractile strength Blood vessels Arteries Dilation (via EDRF. Constriction (high-dose direct effect Dilation (via EDRF. Constriction(high-dose direct effect Lung Bronchial muscle Contraction (bronchoconstriction) Bronchial glands I Stimulation Gastrointestinal tract Motility Increase Sphincters Relaxation Secretion Stimulation Urinary bladder Detrusor Contraction Trigone and sphincter Relaxation Glands Sweat, salivary lacrimal Secreti。n 鼻咽部的 nasopharyngeal不应期 鼻咽部的 M1 M2 M3 M1M3