Regulation of respiration Breathing is controlled by the central neuronal network to meet the metabolic demands of the body Neural regulation -Chemical regulation
Regulation of respiration Regulation of respiration Breathing is controlled by the central neuronal network to meet the metabolic d d f th b d deman ds o f the b o d y – Neural regulation Neural regulation – Chemical regulation Chemical regulation
Respiratory center ■Definition: -A collection of functionally similar neurons that help to regulate the respiratory movement
Respiratory center Respiratory center Definition: – A collection of functionally similar neurons A collection of functionally similar neurons that help to regulate the respiratory movement
Respiratory center ■Medulla Basic respiratory center:produce and control the respiratory ■Pons rhythm Higher respiratory center:cerebral cortex, hypothalamus limbic system Spinal cord:motor neurons
Respiratory center Respiratory center Medulla P Basic respiratory center: produce and control the respiratory Pons Higher respiratory center: cerebral cortex rhythm Higher respiratory center: cerebral cortex, hypot a a us & b c syste h ala mus & lim bic syste m S pinal cord: motor neurons
Neural regulation of respiration Voluntary breathing center -Cerebral cortex Automatic (involuntary)breathing center Medulla -Pons
Neural regulation of respiration Neural regulation regulation of respiration respiration Voluntary breathing center – Cerebral cortex Cerebral cortex Automatic (involuntary) breathing center – Medulla Medulla – Pons
Midbrain Pons Hindbrain
Neural generation of rhythmical breathing Higher CNS The discharge of medullary inspiratory neurons provides rhythmic input to the motor neurons innervating the inspiratory muscles.Then the action potential cease,the inspiratory muscles relax, and expiration occurs as muscles the elastic lungs recoil. Spinel cord Pump muscle时
Neural generation of rhythmical breathing The discharge of medullary inspiratory neurons provides rhythmic input to the motor neurons innervating the inspiratory muscles. Then the action pot ti l th tenti al cease, the inspiratory muscles relax, and expiration occurs as and expiration occurs as the elastic lungs recoil
THE MEDULLA'S CONTROL OF THE RESPIRATORY CYCLE Inspiratory neurons ■Expiratory neurons Sapo Lower motor neurons -Upper motor neurons -Inspiraton center inhibits expiration center
Inspiratory neurons Exp y iratory neurons
Respiratory center Dorsal respiratory group (medulla)-mainly causes inspiration Ventral respiratory group (medulla)-causes either expiration or inspiration Pneumotaxic center (upper pons)-inhibits apneustic center inhibits inspiration,helps control the rate and pattern of breathing Apneustic center (lower pons)-to promote inspiration
Respiratory center Respiratory center Dorsal respiratory group (medulla) – mainly causes ins piration Ventral respiratory group (medulla) (medulla) – causes eith i ti i i ti ither expiration or inspiration Pneumotaxic cente r ( pp p ) upper pons ) – inhibits apneustic center & inhibits inspiration,helps control control the rate and pattern of breathing control the rate and pattern pattern of breathing breathing Apneustic center (lower pons) (lower pons) – to promote to promote inspiration
☐Inspiratory Neurons Inferior Colliculus Pneumotaxic Center N.Parabrachialis Medialis N.KOlliker-Fuse Pons Apneustic Center Dorsal Respiratory Group N.Tractus Solitarius (NTS) Ventral Respiratory Group -Botzinger's Complex Medulla -N.Ambiguus (NA) N.Para-Ambigualis (NPA) Oblongata -N.Retro-Ambigualis (NRA) Spinal Cord
Hering-Breuer inflation reflex (Pulmonary stretch reflex) The reflex is originated in the lungs and mediated by the fibers of the vagus nerve: Pulmonary inflation reflex: inflation of the lungs,eliciting expiration. -Pulmonary inflation reflex: deflation,stimulating inspiration
Hering-Breuer inflation reflex (Pulmonary stretch reflex ) The reflex is originated in the lungs and medi t d b th fib f th di a t e d by the fibers o f the vagus nerve: – Pulmonary inflation reflex: inflation of the lungs, eliciting expiration. – Pulmonary inflation reflex: deflation stimulating inspiration deflation, stimulating inspiration