Apneustic center

The apneustic center (or apneustic area) of the lower pons appears to promote inspiration by stimulation of the I neurons in the medulla oblongata providing a constant stimulus.

The apneustic center of pons sends signals to the dorsal respiratory center in the medulla to delay the 'switch off' signal of the inspiratory ramp provided by the pneumotaxic center of pons. It controls the intensity of breathing. The apneustic center is inhibited by pulmonary stretch receptors. However, it gives positive impulses to the inspiratory (I) neurons.

External links

Description at vcu.edu
Physiology: 4/4ch6/s4ch6_10 - Essentials of Human Physiology

Respiratory physiology

Respiration	breath inhalation exhalation respiratory rate respirometer pulmonary surfactant compliance elastic recoil hysteresivity airway resistance bronchial hyperresponsiveness constriction dilatation mechanical ventilation

Control	pons pneumotaxic center apneustic center medulla dorsal respiratory group ventral respiratory group chemoreceptors central peripheral pulmonary stretch receptors Hering–Breuer reflex

Lung volumes	VC FRC Vt dead space CC PEF calculations respiratory minute volume FEV1/FVC ratio Lung function tests spirometry body plethysmography peak flow meter nitrogen washout

Circulation	pulmonary circulation hypoxic pulmonary vasoconstriction pulmonary shunt

Interactions	Perfusion (V) ventilation (Q) ventilation/perfusion scan zones of the lung gas exchange pulmonary gas pressures alveolar gas equation alveolar–arterial gradient hemoglobin oxygen–haemoglobin dissociation curve (Oxygen saturation 2,3-BPG Bohr effect Haldane effect) carbonic anhydrase (chloride shift) oxyhemoglobin respiratory quotient arterial blood gas diffusion capacity (DLCO)

Insufficiency	high altitude oxygen toxicity hypoxia

Anatomy of the pons

Dorsal/
(tegmentum)

Surface

White: Sensory

Medial longitudinal fasciculus
- Vestibulo-oculomotor fibers

White: Motor

Grey: Cranial nuclei

afferent:	GSA Trigeminal Principal Spinal Cochlear nucleus Dorsal Anterior Vestibular nuclei Superior

efferent:	SVE: Trigeminal motor nucleus Facial motor nucleus GSE: Abducens nucleus GVE: Superior salivary nucleus Inferior salivary nucleus

Other	Apneustic center Parabrachial area Pneumotaxic center Subparabrachial nucleus Medial parabrachial nucleus Lateral parabrachial nucleus Superior olivary nucleus Caerulean nucleus

Ventral/
(base)

Grey	Pontine nuclei

White: Motor/descending	Corticospinal tract Corticobulbar tract Corticopontine fibers MCP Pontocerebellar fibers

Surface	Basilar sulcus

Other grey: Raphe/
reticular

This article is issued from Wikipedia - version of the 4/4/2015. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.