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Ok guys I know this is going to sound stupid, but I don't have my physio book with me at the library, is J-reflex the same as Herring bauer inflation reflex?


I do know however for a fact that J receptors are sensory nerve endings in alv wall in juxtaposition to pulm capillaries. They are stimulated when irritant chemicals are injected into pulm bld or when pulm capillaries become engorged with bld or in pulm edema(as in CHF)

thanks again ppl!
 

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Yes they are the same

Receptors in the airways and lungs are innervated by myelinated and unmyelinated vagal fibers. The unmyelinated fibers are C fibers. The receptors innervated by myelinated fibers are commonly divided into slowly adapting receptors and rapidly adapting receptors on the basis of whether sustained stimulation leads to prolonged or transient discharge in their afferent nerve fibers. The other group of receptors presumably consists of the endings of C fibers, and they are divided into pulmonary and bronchial subgroups on the basis of their location.

The shortening of inspiration produced by vagal afferent activity (Figure 36-3) is mediated by slowly adapting receptors. So are the Hering-Breuer reflexes. The Hering-Breuer inflation reflex is an increase in the duration of expiration produced by steady lung inflation, and the Hering-Breuer deflation reflex is a decrease in the duration of expiration produced by marked deflation of the lung. Because the rapidly adapting receptors are stimulated by chemicals such as histamine, they have been called irritant receptors. Activation of rapidly adapting receptors in the trachea causes coughing, bronchoconstriction, and mucus secretion, and activation of rapidly adapting receptors in the lung may produce hyperpnea.

Because the C fiber endings are close to pulmonary vessels, they have been called J (juxtacapillary) receptors. They are stimulated by hyperinflation of the lung, but they respond as well to intravenous or intracardiac administration of chemicals such as capsaicin. The reflex response that is produced is apnea followed by rapid breathing, bradycardia, and hypotension (pulmonary chemoreflex). A similar response is produced by receptors in the heart (Bezold-Jarisch reflex or the coronary chemoreflex; The physiologic role of this reflex is uncertain, but it probably occurs in pathologic states such as pulmonary congestion or embolization, in which it is produced by endogenously released substances.
 
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