Airway reversibility and inflammation in stable pre- to late-adolescent asthmatics without long-term control medications.

Pulmonary function and airway inflammation were investigated in stable pre- to late-adolescent asthmatics without long-term control medications and compared with those in currently medicated asthmatics. Subjects comprised 34 well-controlled asthmatic children (aged 8.1-18.

Optimal step-down approach for pediatric asthma controlled by salmeterol/fluticasone: A randomized, controlled trial (OSCAR study).

Background: Several guidelines, including the Japanese Pediatric Guideline for the Treatment and Management of Asthma (JPGL), recommend salmeterol/fluticasone combination therapy (SFC) as step 3 to 4 treatment for moderate to severe asthma. However, the optimal step-down approach to SFC remains unclear. In the current study, we examined step-down approaches in asthmatic children whose symptoms had been stabilized by SFC 100/200 μg/day.

Effect of disodium cromoglycate on airway mucus secretion during antigen-induced late asthmatic responses in a murine model of asthma.

Background: Disodium cromoglycate (DSCG) is known to inhibit both immediate and late asthmatic responses (IAR and LAR). However, its effect on mucus hypersecretion is unknown. Using a murine model of asthma, we aimed to determine whether mucus secretion increased during IAR and LAR.

Airway responsiveness and airway remodeling after chronic exposure to procaterol and fenoterol in guinea pigs in vivo.

Background: Chronic exposure to fenoterol (FEN), a beta(2)-adrenergic receptor (beta(2)-AR) agonist, was shown to induce both airway hyperresponsiveness and airway remodeling in experimental animals.

Objective: We wanted to know the effects of chronic exposure to procaterol (PRO), a beta(2)-AR agonist, on airway function and structure, because this agent is widely used as a bronchodilator in Japan. For comparison, the effects of FEN were also examined.

Maturational changes in airway remodeling after chronic exposure to ovalbumin in sensitized guinea pigs: role of cell renewal of airway resident cells.

We wanted to know whether airway remodeling caused by chronic exposures to antigen differed depending on the degree of maturation of animals. We sensitized guinea pigs at different stages of maturation: juvenile (approximately 200 g in body weight), adult (400 g), and old animals (800 g). Then, animals were repeatedly challenged with inhaled ovalbumin (0.

Effects of STA(2), a thromboxane A(2) mimetic, in inducing airflow obstruction and airway microvascular leakage in guinea pigs.

Background: U-46619, a thromboxane A(2) (TXA(2)) mimetic, is shown to cause airway microvascular leakage, although the effects is weak when comparing with that to induce bronchoconstriction in guinea pigs.

Objective: In order to know the airway effect of TXA(2) more accurately, we have examined the effects of STA(2), a TXA(2) mimetic with higher affinity to TXA(2) (TP) receptors than U-46619, to induce airway microvascular leakage and airflow obstruction.

Methods: Anesthetized and ventilated guinea pigs were i.

Effects of Y-27632, a Rho/Rho kinase inhibitor, on leukotriene D(4)- and histamine-induced airflow obstruction and airway microvascular leakage in guinea pigs in vivo.

Recent in vitro studies have shown that the Rho/Rho kinase pathway is involved in the mechanism of not only airway smooth muscle contraction but also vascular endothelial permeability caused by certain stimuli. This suggests that Rho/Rho kinase inhibitors may become useful agents against asthma via reduction of increased airway microvascular leakage, one of the main features of this disease. Thus, we wanted to know the in vivo effect of Y-27632, a selective Rho kinase inhibitor, on airway microvascular leakage caused by leukotriene D(4) (LTD(4)) and histamine, potent mediators of allergic airway inflammation, by comparing its effect against airflow obstruction.