Regulation of Cardiovascular Activities 夏强， PhD 浙江大学基础医学系

Control of Cardiovascular Activities Nervous Regulation Humoral Regulation Autoregulation

Innervation of the heart Cardiac sympathetic nerve Cardiac vagus nerve 1. 起源 origin 2. 节前纤维 preganglionic fiber 3. 外周神经节 ganglion 4. 节后纤维 postganglionic fiber 5. 支配 distribution 6. 递质 neurotransmitter

Cardiac autonomic actions Cardiac sympathetic actions – Positive chronotropic effect 正性变时作用 – Positive dromotropic effect 正性变传导作用 – Positive inotropic effect 正性变力作用 Cardiac parasympathetic actions – Negative chronotropic effect 负性变时作用 – Negative dromotropic effect 负性变传导作用 – Negative inotropic effect 负性变力作用

Predominance of autonomic nerves

Innervation of the blood vessels Vasoconstrictor nerve 缩血管神经 – Sympathetic vasoconstrictor nerve 交感缩血管神经 Vasodilator nerve 舒血管神经 – Sympathetic vasodilator nerve 交感舒血管神经 – Parasympathetic vasodilator nerve 副交感舒血管神 经 – Dorsal root vasodilator nerve 脊髓背根舒血管神经

Vasomotor center Located bilaterally mainly in the reticular substance of the medulla and of the lower third of the pons –Vasoconstrictor area –Vasodilator area –Cardioinhibitor area – dorsal nuclei of the vagus nerves and ambiguous nucleus –Sensory area – tractus solitarius

Baroreceptor Reflexes Arterial baroreceptors –Carotid sinus receptor –Aortic arch receptor Afferent nerves (Buffer nerves) Cardiovascular center: medulla Efferent nerves: cardiac sympathetic nerve, sympathetic constrictor nerve, vagus nerve Effector: heart & blood vessels

Reflex pathway

Baroreceptor neurons deliver MAP information to the medulla oblongata’s cardiovascular control center (CVCC); the CVCC determines autonomic output to the heart. i.e., MAP is above homeostatic set point i.e., reduce cardiac output

The End.