Which cardiovascular reflex is specifically triggered by distension of the pulmonary vasculature and causes reflex bradycardia and hypotension (similar to Bezold-Jarisch reflex)?
- A Bainbridge reflex
- B Pulmonary chemoreflex (Pulmonary J-receptor reflex) ✓
- C Cushing reflex
- D Carotid sinus reflex
Correct answer: B. Pulmonary chemoreflex (Pulmonary J-receptor reflex)
Explanation
The pulmonary J-receptor (juxtacapillary receptor) reflex is triggered by pulmonary capillary engorgement, inflammatory mediators, and microemboli. It causes rapid shallow breathing, bradycardia, hypotension, and laryngospasm — similar in mechanism to the Bezold-Jarisch reflex. The Bainbridge reflex causes tachycardia with atrial distension; the Cushing reflex is a hypertensive-bradycardia response to raised ICP; the carotid sinus reflex mediates baroreceptor-dependent heart rate control.
Reference: Guyton & Hall, Textbook of Medical Physiology, 14th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.