BIOC34H3 Lecture Notes - Lecture 14: Ventral Respiratory Group, Dorsal Respiratory Group, Pulmonary Stretch Receptors
Document Summary
If brain is transected above midbrain, breathing continues completely unimpeded. If midbrain removed, eupnea replaced by apneustic breathing- respiratory muscles active, airflow stops. It is auto-resuscitative, and can be caused by hypoxia or ischemia. It is an integrative center, taking neural input from drg and the rhythm generator and modifies info to produce the motor output that drives respiratory muscles. Neural activity generated in pre-b tzinger complex goes to. Vrg for modification before transmitted along the respiratory motor neurons to drive the respiratory muscles: when disabled, breathing becomes ataxic (irregular) and if complex is destroyed, breathing stops. If animal with destroyed pre-b tzinger complex is put on artificial ventilation for 1h (following destruction of the pre-bot), breathing will resume spontaneously. This indicates that there is a redundant rhythm generator located in the brain (if. Glomus cells release neurotransmitters, mainly acetylcholine and dopamine. Under hypoxic conditions, o2 levels are diminished, so conversion is slowed.
