visceral pleura

Examples of visceral pleura in the following topics:

• The Mechanics of Human Breathing

  • The layer of tissue that covers the lung and dips into spaces is called the visceral pleura.
  • A second layer of parietal pleura lines the interior of the thorax .
  • A tissue layer called pleura surrounds the lung and interior of the thoracic cavity.

• Intercostal Nerves

  • The intercostal nerves are distributed chiefly to the thoracic pleura and abdominal peritoneum and differ from the anterior divisions of the other spinal nerves in that each pursues an independent course without plexus formation.
  • Unlike the nerves from the autonomic nervous system that innervate the visceral pleura of the thoracic cavity, the intercostal nerves arise from the somatic nervous system.
  • This enables them to control the contraction of muscles, as well as provide specific sensory information regarding the skin and parietal pleura.
  • Damage to the visceral pleura is experienced as an unlocalized ache.

• Lungs

  • The outer layer of the lungs are the pleura, a type of mesothelium (membrane tissue) that surrounds the lung and attaches it to the thoracic cavity.
  • The pleura contain two layers, the outer parietal pleura (attached to the thoracic cavity), and the inner visceral pleura (covers the lungs).
  • The pleural cavity is the fluid-filled space between the parietal and visceral pleura, and provides room for the lung to expand during inhalation.

• Pericardium

  • The pericardium is one of the mesothelium tissues of the thoracic cavity, along with the pleura which cover the lungs.
  • The inner layer is known as the visceral layer, which covers and protects the great vessels and heart.
  • The space between the parietal and visceral layers is called the pericardial cavity.
  • The visceral layer is referred to as the epicardium in the areas where it is in direct contact with the heart.
  • The pleural and pericardial cavities are exaggerated since normally there is no space between parietal and visceral pleura and between pericardium and heart.

• Autonomic Plexuses

  • Autonomic plexuses are formed from both sympathetic and parasympathetic fibers and innervate visceral organs to regulate overall activity.
  • Autonomic plexuses are formed from sympathetic postganglionic axons, parasympathetic preganglionic axons, and some visceral sensory axons.
  • It supplies the Bronchial tree and the visceral pleura.
  • Esophageal: The esophageal plexus is formed by nerve fibers from two sources: branches of the vagus nerve and visceral branches of the sympathetic trunk.

• Serous Membranes

  • Early in embryonic life, visceral organs develop adjacent to a cavity and invaginate into the bag-like coelom.
  • The layer in contact with the organ is known as the visceral layer, while the parietal layer is in contact with the body wall.
  • The pleural and pericardial cavities are exaggerated since normally there is no space between parietal and visceral pleura and between pericardium and heart.

• Body Cavity Membranes

  • The mesothelium is a membrane that forms the lining of several body cavities: the pleura (thoracic cavity), peritoneum (abdominal cavity including the mesentery) and pericardium (heart sac).
  • Mesothelium that covers the internal organs is called visceral mesothelium, while the layer that covers the body walls is called the parietal mesothelium.

• Glossopharyngeal (IX) Nerve

  • It receives visceral sensory fibers from the carotid bodies, carotid sinus.
  • Visceral motor (general visceral efferent) - provides parasympathetic innervation of the parotid gland.
  • Visceral sensory (general visceral afferent) - carries visceral sensory information from the carotid sinus and body.

• Autonomic Reflexes

  • Autonomic reflexes are unconscious motor reflexes relayed from organs and glands to the CNS through visceral afferent signaling.
  • The autonomic nervous system (ANS or visceral nervous system or involuntary nervous system) is the part of the peripheral nervous system that acts as a control system.
  • It functions largely below the level of consciousness, and controls visceral functions.
  • General visceral afferent sensations are mostly unconscious visceral motor reflex sensations from hollow organs and glands that are transmitted to the CNS (see for a depiction of a typical nerve fiber, including general visceral afferent fibers).
  • The pain is also usually referred to dermatomes that are at the same spinal nerve level as the visceral afferent synapse.

• Branches of Spinal Nerves

  • The dorsal ramus: Contains nerves that serve the dorsal portions of the trunk carrying visceral motor, somatic motor, and sensory information to and from the skin and muscles of the back.
  • The ventral ramus: Contains nerves that serve the remaining ventral parts of the trunk and the upper and lower limbs carrying visceral motor, somatic motor, and sensory information to and from the ventrolateral body surface, structures in the body wall, and the limbs.
  • The rami communicantes: Contain autonomic nerves that carry visceral motor and sensory information to and from the visceral organs.