Section 6 Respiratory physiology

Most lung volumes can be measured with a spirometer except total lung capacity (TLC), functional residual capacity (FRC) and residual volume (RV). The FRC can be measured by helium dilution or body plethysmography. 

The volume of gas which is inhaled or exhaled during the course of a normal resting breath. Also represented by the symbol l/r (ml). 

The volume of gas that remains in the lungs after a maximal forced expiration (ml). 

The volume of gas that can be further inhaled after the end of a normal tidal inhalation (ml). 

---

The mouse respiratory depression model of Alarie, which is described in more detail in the section on physiological assessment, provides a lung function-based... 

CP-channels with even smaller conductance have been described for the lacrimal and other exocrine glands [76,77]. These channels have a conductance of 1-2 pS. Unlike the ICOR-channel they appear to be blocked by millimolar concentrations of furosemide [77]. Most recent and only partially published data from my own laboratory obtained with the above modified nystatin technique [50,133,134] indicate that the respiratory epithelial cells and colonic carcinoma cells possess these types of small CP channels, and that these channels are involved in hormonal regulation of CP-conductance (cf. section 5). These CP-channels are regulated by cytosolic Ca. Hormonally induced increases in cytosolic Ca lead to an abrupt increase in the probability of these small CP-channels being open, yet they have no effect on the ICOR-channel. Data of this kind reinforce that the physiological importance of these small CP-channels may have been grossly underestimated. 

Lippmann, M. (1977). Regional deposition of particles in the human respiratory tract , Section 9, page 213 in HANDBOOK OF PHYSIOLOGY, Lee, H. D. K. Sect. Ed., (American Physiological Society, Bethesda, Md.). 

For substances with local effects on the respiratory tract, no general approach for interspecies scaling can be given. Anatomical and physiological differences in the airways between experimental animals and humans contribute to interspecies differences in local effects observed between animals and humans, see Section 4.7.8. It should be noted, however, that for local effects the determining factor for effects to occur in the respiratory tract is generally the concentration of the chemical in the air rather than the total dose and thus allometric scaling is not relevant. 

Casida JE, Toia RF. Organophosphorus pesticides their target diversity and bioactivation. In Dekant W, Neumann HG, eds. Tissue Specific Toxicity Biochemical Mechanisms. London Academic Press, 1992. Coburn RF, Forman HJ. Carbon monoxide toxicity. In Fahri LE, Tenney SM, eds. Flandbook of Physiology, The Respiratory System, Section 3, Vol. IV, Bethesda, MD American Physiology Society, 1987. Ellenhorn MJ, Barceloux DG. Medical Toxicology, New York Elsevier, 1988. 

Figure 27.6. Ultrastructure of the alveolar respiratory membrane shown in cross section. (Adapted from Guyton, A. C., and Hall, J. E. Textbook of Medical Physiology, 10th edition, W.B. Saunders, Philadelphia, 2000. This figure was completely redrawn by the author from materials cited.)...

Since the human respiratory tract is anatomically and physiologically a very heterogeneous system, the rate and extent of absorption of macromolecules as well as their potential adverse reactions depend on the regional doses. The most convenient method to deliver drugs to the respiratory tract is by inhalation. Other methods of delivery such as intratracheal instillation are used in experimental settings but are generally unsuitable for real-life therapeutic products. This section... 

Coleridge HM, Coleridge JCG (1986) Reflexes evoked from tracheobronchial tree and lungs. In Cherniak NS, Widdicombe JG (eds) Handbook of Physiology, Section 3 The Respiratory System, Vol. II Control of Breathing, Part I, American Physiological Society, Washington, DC, pp 395-429... 

SECTION 6.2 THE RESPIRATORY SYSTEM IN ACID-BASE PHYSIOLOGY... 

---