Juxtacapillary (J) receptors
Encyclopedia
J-receptors are nerve
s innervating into the body of the lung
. They are present in the alveolar interstitium and are innervated by fibers of the vagus nerve
. J-receptors respond to events such as pulmonary edema
, pulmonary emboli, pneumonia
, and barotrauma
, which cause a decrease in oxygenation and thus lead to an increase in ventilation
/respiration. They may be also stimulated by hyperinflation of the lung as well as intravenous or intracardiac administration of chemicals.
The stimulation of the J-receptors causes a reflex
increase in breathing rate, and is also thought to be involved in the sensation of dyspnea
, the subjective sensation of difficulty breathing.
The reflex response that is produced is apnea followed by rapid breathing, bradycardia, and hypotension (pulmonary chemoreflex). The physiologic role of this reflex is uncertain, but it probably occurs in pathologic states such as pulmonary congestion or embolization..These receptors were discovered by Dr. A.S Paintal.
Nerve
A peripheral nerve, or simply nerve, is an enclosed, cable-like bundle of peripheral axons . A nerve provides a common pathway for the electrochemical nerve impulses that are transmitted along each of the axons. Nerves are found only in the peripheral nervous system...
s innervating into the body of the lung
Lung
The lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart...
. They are present in the alveolar interstitium and are innervated by fibers of the vagus nerve
Vagus nerve
The vagus nerve , also called pneumogastric nerve or cranial nerve X, is the tenth of twelve paired cranial nerves...
. J-receptors respond to events such as pulmonary edema
Pulmonary edema
Pulmonary edema , or oedema , is fluid accumulation in the air spaces and parenchyma of the lungs. It leads to impaired gas exchange and may cause respiratory failure...
, pulmonary emboli, pneumonia
Pneumonia
Pneumonia is an inflammatory condition of the lung—especially affecting the microscopic air sacs —associated with fever, chest symptoms, and a lack of air space on a chest X-ray. Pneumonia is typically caused by an infection but there are a number of other causes...
, and barotrauma
Barotrauma
Barotrauma is physical damage to body tissues caused by a difference in pressure between an air space inside or beside the body and the surrounding fluid...
, which cause a decrease in oxygenation and thus lead to an increase in ventilation
Ventilation (physiology)
In respiratory physiology, ventilation is the rate at which gas enters or leaves the lung. It is categorized under the following definitions:-Sample values:...
/respiration. They may be also stimulated by hyperinflation of the lung as well as intravenous or intracardiac administration of chemicals.
The stimulation of the J-receptors causes a reflex
Reflex
A reflex action, also known as a reflex, is an involuntary and nearly instantaneous movement in response to a stimulus. A true reflex is a behavior which is mediated via the reflex arc; this does not apply to casual uses of the term 'reflex'.-See also:...
increase in breathing rate, and is also thought to be involved in the sensation of dyspnea
Dyspnea
Dyspnea , shortness of breath , or air hunger, is the subjective symptom of breathlessness.It is a normal symptom of heavy exertion but becomes pathological if it occurs in unexpected situations...
, the subjective sensation of difficulty breathing.
The reflex response that is produced is apnea followed by rapid breathing, bradycardia, and hypotension (pulmonary chemoreflex). The physiologic role of this reflex is uncertain, but it probably occurs in pathologic states such as pulmonary congestion or embolization..These receptors were discovered by Dr. A.S Paintal.