Bezold-Jarisch reflex is mediated by:
(A) Serotonin (B) Angiotensin (C) Prostaglandin (D) Histamine
(A) Answer- A. SerotoninThe Bezold-Jarisch reflex involves a variety of cardiovascular and neurological processes which cause hypopnea (excessively shallow breathing or an abnormally low respiratory rate) and bradycardia (abnormally low resting hea rate). Serotonin can elicit Bezold-Jarisch reflex.Bezold-Jarisch reflex responds to noxious ventricular stimuli sensed by chemoreceptors & mechanoreceptors within the LV wall by inducing the triad of hypotension bradycardia & coronary aery dilatation.Stimulation of aerial baroreceptors or ventricular baroreceptors by any of a host of chemicals-veratrum alkaloids, nicotine capsaicin, anti-histamine serotonin snake and insect venoms--can also trigger the Bezold- Jarisch reflex.