mechanism of negative chronotropic effect ↓Ca→ Lautomatic depolarization mechanism of negative dromotropic effect T ERP of Atrioventricular node purkinje fibers i conduction mechanism of negative inotropic effect atrium:↑K+efux>↑ repolarization action potential duration l, ERPV, Ca2+v ventricles: presynaptic membrane M-R NA release
mechanism of negative chronotropic effect ↓Ca2+ →↓automatic depolarization mechanism of negative dromotropic effect ↑ ERP of Atrioventricular node & Purkinje fibers →↓conduction mechanism of negative inotropic effect atrium: ↑ K+ efflux→ ↑ repolarization → action potential duration ↓ , ERP↓，Ca2+ ventricles: presynaptic membrane M-R →NA release↓
(2) splanchnic smooth muscle O gastrointestinal tract: excitation ,s motility increase; secretion stimulation ② urinary bladder: detrusor(逼尿肌) contraction 令 trigone(三角区) sphincter relaxation ③ bronchus: contraction
(2) splanchnic smooth muscle ① gastrointestinal tract: excitation ❖ motility increase; secretion stimulation ② urinary bladder: ❖ detrusor (逼尿肌) contraction ❖ trigone (三角区) sphincter relaxation ③ bronchus: contraction
3)others O glands secretion: increasingly 2) eyes miosis (iris sphincter contraction near vision(ciliary muscle contraction)
(3) others ① glands secretion: increasingly ② eyes: miosis (iris sphincter contraction ) near vision (ciliary muscle contraction)
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
2. nicotinic actions (ganglion, skeletal muscle, adrenal medulla NH-R: co-innervation and dominant theory adrenaline release N-R: skeletal muscle contraction
2. nicotinic actions (ganglion, skeletal muscle, adrenal medulla) ❖ NN -R: co-innervation and dominant theory adrenaline release ❖ NM -R: skeletal muscle contraction