Respiratory Structure and Mechanics
Respiratory Structure and Mechanics
The branching of airways.
Air flow through an airway is inversely proportional to airway resistance, which is proportional to the length of the airway, is proportional to the viscosity of the air, and is inversely proportional to the fourth power of the radius of the airway. Lung compliance, which is the ability of lung to stretch, is inversely proportional to alveolar surface tension, which resists the expansion of alveoli. The law of LaPlace states that the inward pressure of a bubble due to surface tension is inversely proportional to the radius of the bubble. Surfactants reduce surface tension.
Alveolar interdependence.
Obstructive lung disease involves an increase in airway resistance. Restrictive lung disease involves a decrease in lung compliance.
51
Lung volumes and capacities.
Residual volume and functional residual volume can be determined by the helium dilution method.
Forced expiry volume in one second and forced expiry volume to forced vital capacity ratio.
52
The effect of anatomic dead space.
!($,'" 7"$'()#'(/$ AC = D(:#) 7/),8" (DA) × G&"H,"$0< /I 7"$'()#'(/$ (I) J)7"/)#& 7"$'()#'(/$ AK = DA − A/),8" /I :"#: +*#0" × I Alveolar ventilation is increased more efficiently by increasing tidal volume than by increasing frequency of ventilation.
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Drugs as Tools for Understanding Biology Reserpine Reserpine was used to treat hypertension until more selective drugs were available. Reserpine causes the depletion of noradrenaline, dopamine, and serotonin in the CNS and the PNS.
Reserpine blocks the sympathetic nervous system by inhibiting dopamine transporters.
Reserpine can be used to determine actions of the sympathetic nervous system, and in the study of Parkinson’s disease, depression, and schizophrenia.
Prazosin The action of prazosin contributed to the discovery that a single nerve can release multiple transmitters. Co-transmitters of noradrenaline in sympathetic nerves include ATP, which produces instant responses by binding to ion channel receptors, and neuropeptide Y, which produces delayed responses by binding to G-protein-coupled receptors.
Clonidine The action of clonidine contributed to the discovery of prejunctional neurotransmitter receptors that feedback negativity to the release of neurotransmitter.
Drugs That Prevent Transplant Rejection Cyclosporine and tacrolimus are very potent immunosuppressant drugs that act in a similar way.
7
The action of cyclosporine and tacrolimus contributed to the discovery of the role of calcineurin in T cell proliferation, and contributed to the discovery of immunophilins in controlling the action of calcineurin.
Drugs That Inhibit Cell Signalling Pathways PP2 is a potent inhibitor of the Src family of tyrosine kinases that inhibits other families of tyrosine kinases with less potency.
8
The branching of airways.
Air flow through an airway is inversely proportional to airway resistance, which is proportional to the length of the airway, is proportional to the viscosity of the air, and is inversely proportional to the fourth power of the radius of the airway. Lung compliance, which is the ability of lung to stretch, is inversely proportional to alveolar surface tension, which resists the expansion of alveoli. The law of LaPlace states that the inward pressure of a bubble due to surface tension is inversely proportional to the radius of the bubble. Surfactants reduce surface tension.
Alveolar interdependence.
Obstructive lung disease involves an increase in airway resistance. Restrictive lung disease involves a decrease in lung compliance.
51
Lung volumes and capacities.
Residual volume and functional residual volume can be determined by the helium dilution method.
Forced expiry volume in one second and forced expiry volume to forced vital capacity ratio.
52
The effect of anatomic dead space.
!($,'" 7"$'()#'(/$ AC = D(:#) 7/),8" (DA) × G&"H,"$0< /I 7"$'()#'(/$ (I) J)7"/)#& 7"$'()#'(/$ AK = DA − A/),8" /I :"#: +*#0" × I Alveolar ventilation is increased more efficiently by increasing tidal volume than by increasing frequency of ventilation.
53
Drugs as Tools for Understanding Biology Reserpine Reserpine was used to treat hypertension until more selective drugs were available. Reserpine causes the depletion of noradrenaline, dopamine, and serotonin in the CNS and the PNS.
Reserpine blocks the sympathetic nervous system by inhibiting dopamine transporters.
Reserpine can be used to determine actions of the sympathetic nervous system, and in the study of Parkinson’s disease, depression, and schizophrenia.
Prazosin The action of prazosin contributed to the discovery that a single nerve can release multiple transmitters. Co-transmitters of noradrenaline in sympathetic nerves include ATP, which produces instant responses by binding to ion channel receptors, and neuropeptide Y, which produces delayed responses by binding to G-protein-coupled receptors.
Clonidine The action of clonidine contributed to the discovery of prejunctional neurotransmitter receptors that feedback negativity to the release of neurotransmitter.
Drugs That Prevent Transplant Rejection Cyclosporine and tacrolimus are very potent immunosuppressant drugs that act in a similar way.
7
The action of cyclosporine and tacrolimus contributed to the discovery of the role of calcineurin in T cell proliferation, and contributed to the discovery of immunophilins in controlling the action of calcineurin.
Drugs That Inhibit Cell Signalling Pathways PP2 is a potent inhibitor of the Src family of tyrosine kinases that inhibits other families of tyrosine kinases with less potency.
8
