Pulmonary surfactant is a lipoprotein complex structure secreted by type II alveolar cells that have surface-active features. It consists of hydrophilic and hydrophobic sites. The primary function of surfactant is to reduce surface tension by adsorbing to the water-air division surface of the alveoli.
Functions
- To increase lung compliance.
- Atelectasis prevention (collapse of the lung) at the end of exhalation.
- To restore collapsed airways
Secretion of surfactant
Secretion from cells can occur by constitutive and regulated pathways simultaneously. Constitutive secretion, in which substances are secreted continuously without prior concentration and storage, has not been studied in detail in type II cells. It is possible, although unstudied, that constitutive, as well as regulated pathways, secrete one or more components of surfactant and that the two pathways may be utilized to differing extents during various states of health and disease. Studies in type II cells have focused on regulated secretion, in which a stimulus causes previously synthesized material stored in cytoplasmic organelles to release from the cell. In type II cells, regulated secretion occurs by classical exocytosis. Extracellular stimuli modulate intracellular chemical events, which result in movement of lamellar bodies towards the apical surface of the type II cell, apposition of lamellar bodies to the apical plasma membrane, fusion of the limiting membrane of the lamellar bodies with the plasma membrane, and extrusion of lamellar body contents into the alveolus. It is likely that various intracellular second messengers, cytoskeletal elements, protein phosphorylation and dephosphorylation, and membrane fusion proteins are all involved in exocytosis in type II cells. The steps linking the initial stimulus to the eventual secretion of lamellar bodies are incompletely understood.
Nanobot Medical Animation Studio develops highly innovative digital graphics to depict actual and conceptual technologies by a synergistic fusion of art and science since 2007. Nanobot provides visually engaging digital solutions like scientific VR/AR/MR, 3D medical animations, illustrations for innovative marketing and training | education strategies to the pharmaceutical and biotech industry.We are devoted entirely to medical and scientific imaging. Our creative production team and experienced medical experts help us produce visually and scientifically accurate media material to make any project a huge success.We are a professional medical animation and interactive design company whose team has a long history of experience in the creation of latter-day colorful photo-realistic animated or static images.
Our client ranges from the Medical Device, Pharmaceutical and Biotechnology Industry, as well as Educational Institutes, Medical Marketing Companies, and Healthcare Agencies Globally.