OBJECTIVE: To determine the extent to which thin-section and volumetric three-dimensional CT can depict airway reactivity to bronchostimulator, and to assess the effect of different airway sizes on the degree of reactivity. MATERIALS AND METHODS: In eight dogs, thin-section CT scans were obtained before and after the administration of methacholine and ventolin. Cross-sectional areas of bronchi at multiple levels, as shown by axial CT, proximal airway volume as revealed by three-dimensional imaging, and peak airway pressure were mea-sured. The significance of airway change induced by methacholine and ventolin, expressed by percentage changes in cross-sectional area, proximal airway volume, and peak airway pressure was statistically evaluated, as was correlation between the degree of airway reactivity and the area of airways. RESULTS: Cross-sectional areas of the bronchi decreased significantly after the administration of methacholine, and scans obtained after a delay of 5 minutes showed that normalization was insufficient. Ventolin induced a significant increase in cross-sectional areas and an increase in proximal airway volume, while the effect of methacholine on the latter was the opposite. Peak airway pres-sure increased after the administration of methacholine, and after a 5-minute delay its level was near that of the control state. Ventolin, however, induced no significant decrease. The degree of airway reactivity did not correlate with airway size. CONCLUSION: Thin-section and volumetric spiral CT with three-dimensional reconstruction can demonstrate airway reactivity to bronchostimulator. The degree of reactivity did not correlate with airway size.
Albuterol/pharmacology ; Animal ; Bronchoconstriction/*physiology ; Bronchoconstrictor Agents/*pharmacology ; Bronchodilator Agents/*pharmacology ; Dogs ; *Imaging, Three-Dimensional ; Methacholine Chloride/pharmacology ; Tomography, X-Ray Computed/*methods

Adolescent ; Adult ; Aged ; Albuterol ; pharmacology ; therapeutic use ; Asthma ; drug therapy ; Child ; Female ; Heart Rate ; drug effects ; Humans ; Male ; Middle Aged ; Terbutaline ; pharmacology ; therapeutic use

Cholera toxin, which has been frequently used as mucosal adjuvant, leads to an irreversible activation of adenylyl cyclase, thereby accumulating cAMP in target cells. Here, it was assumed that beta2-adrenergic agonist salbutamol may have modulatory functions of immunity induced by DNA vaccine, since beta2-adrenergic agonists induce a temporary cAMP accumulation. To test this assumption, the present study evaluated the modulatory functions of salbutamol co-administered with DNA vaccine expressing gB of herpes simplex virus (HSV) via intranasal (i.n.) route. We found that the i.n. co-administration of salbutamol enhanced gB-specific IgG and IgA responses in both systemic and mucosal tissues, but optimal dosages of co-administered salbutamol were required to induce maximal immune responses. Moreover, the mucosal co-delivery of salbutamol with HSV DNA vaccine induced Th2-biased immunity against HSV antigen, as evidenced by IgG isotypes and Th1/Th2-type cytokine production. The enhanced immune responses caused by co-administration of salbutamol provided effective and rapid responses to HSV mucosal challenge, thereby conferring prolonged survival and reduced inflammation against viral infection. Therefore, these results suggest that salbutamol may be an attractive adjuvant for mucosal genetic transfer of DNA vaccine.
Adjuvants, Immunologic/*pharmacology ; Adrenergic beta-Agonists/immunology/*pharmacology ; Albuterol/immunology/*pharmacology ; Animals ; Antibodies, Viral/immunology ; Cercopithecus aethiops ; Cytokines/immunology ; Dose-Response Relationship, Drug ; Dose-Response Relationship, Immunologic ; Herpes Simplex/immunology/*prevention & control ; Herpes Simplex Virus Vaccines ; Immunity, Mucosal/*drug effects/immunology ; Immunoglobulin A/immunology ; Immunoglobulin G/immunology ; Mice ; Simplexvirus/*immunology ; Th1 Cells/immunology ; Th2 Cells/immunology ; Vaccines, DNA/*immunology/pharmacology ; Vero Cells ; Viral Envelope Proteins/immunology