BIOC34H3 Lecture Notes - Lecture 14: Dorsal Respiratory Group, Ventral Respiratory Group, Solitary Tract
Document Summary
Dorsal respiratory group (same as nucleus tractus solitarus (nts) in mammals) Drg: located in the pons, 2 main nuclei: Nucleus parabranchialis: role: termination in inspiration, and switching from inspiration to expiration, a good ex. The stretch r"s in the lungs perform the same function. Helps increase chances of survival if one of the primary control systems fail: also called apneustic centre . If the connection btw midbrain + pons is severed results in prolonged inhalation (apneustic breathing) In summary: the pons modifies the output of medullary centers. Important relay centre: modifies breathing pattern, the ventral respiratory group (vrg) responsible for rhythmicity of breathing, 3 main nuclei: You see the importance of this complex when it becomes disabled! Breathing becomes ataxic (no movement) and irregular. Can insert artificial ventilation for 1 hr immediately after destruction breathing resumes. Ach acts post-synaptically on carotid sinus nerve. Da acts as feedback inhibitor prevents ach release: the mitochondrial model of o2 chemoreception.
