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Does unrestrained single-chamber plethysmography provide a valid assessment of airway responsiveness in allergic BALB/c mice?

Zhang Q, Lai K, Xie J, Chen G, Zhong N - Respir. Res. (2009)

Bottom Line: Compared with controls, a significant increase in airway responsiveness was shown in the OVA-1D-N group (P < 0.05) but not in the OVA-1D-I group.The invasive measurement is specific to lower airway.Penh measurement (done as a screening procedure), must be confirmed by a direct invasive measurement specific to lower airway in evaluating lower airway responsiveness.

View Article: PubMed Central - HTML - PubMed

Affiliation: State Key Laboratory of Respiratory Disease (Guangzhou Medical University), The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, PR China. Dr.zhang68@yahoo.com

ABSTRACT

Background: Unrestrained plethysmography has been used to monitor bronchoconstriction because of its ease of use and ability to measure airway responsiveness in conscious animals. However, its reliability remains controversial.

Objective: To investigate if unrestrained plethysmography could provide a valid interpretation of airway responsiveness in allergic BALB/c mice.

Methods: Ovalbumin sensitized BALB/c mice were randomized to receive either a single-dose Ovalbumin challenge (OVA-1D group) or a three-dose Ovalbumin challenge (OVA-3D group). The OVA-1D group was further divided into OVA-1D-I (measured invasively, using lung resistance as the index of responsiveness) and OVA-1D-N group (measured non-invasively, using Penh as the index of responsiveness). Similarly the OVA-3D group was divided into OVA-3D-I and OVA-3D-N groups based on the above methods. The control groups were sensitized and challenged with normal saline. Bronchial alveolar lavage fluid was taken and airway histopathology was evaluated for airway inflammation. Nasal responsiveness was tested with histamine challenge.

Results: Compared with controls, a significant increase in airway responsiveness was shown in the OVA-1D-N group (P < 0.05) but not in the OVA-1D-I group. Both OVA-3D-I and OVA-3D-N groups showed higher responsiveness than their controls (P < 0.05). The nasal mucosa was infiltrated by eosinophic cells in all Ovalbumin immunized groups. Sneezing or nasal rubbing in allergic groups appeared more frequent than that in the control groups.

Conclusion: Penh can not be used as a surrogate for airway resistance. The invasive measurement is specific to lower airway. Penh measurement (done as a screening procedure), must be confirmed by a direct invasive measurement specific to lower airway in evaluating lower airway responsiveness.

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Related in: MedlinePlus

Protocol for ovalbumin (OVA) intraperitoneal (i.p.) sensitization and subsequent OVA intranasal (i.n.) challenge. Mice were sensitized by an intraperitoneal injection of 10 μg OVA on days 0, 7 and 14, followed by daily intranasal challenges with 0.2% OVA. OVA-1D-N was challenged on day 28 and airway responsiveness was carried out on day 29 by Penh measurements. OVA-1D-I were challenged on day 28 and airway responsiveness was carried out on day 29 by invasive methods. OVA-3D-N were challenged on days 28, 29, 30 and airway responsiveness was carried out on day 31 by Penh measurements. OVA-3D-I were challenged on days 28, 29, 30 and airway responsiveness was carried out on day 31 by invasive methods.
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Figure 1: Protocol for ovalbumin (OVA) intraperitoneal (i.p.) sensitization and subsequent OVA intranasal (i.n.) challenge. Mice were sensitized by an intraperitoneal injection of 10 μg OVA on days 0, 7 and 14, followed by daily intranasal challenges with 0.2% OVA. OVA-1D-N was challenged on day 28 and airway responsiveness was carried out on day 29 by Penh measurements. OVA-1D-I were challenged on day 28 and airway responsiveness was carried out on day 29 by invasive methods. OVA-3D-N were challenged on days 28, 29, 30 and airway responsiveness was carried out on day 31 by Penh measurements. OVA-3D-I were challenged on days 28, 29, 30 and airway responsiveness was carried out on day 31 by invasive methods.

Mentions: OVA immunized mice were divided into four groups based on their treatment and measurement of airway responsiveness (see Figure 1).


Does unrestrained single-chamber plethysmography provide a valid assessment of airway responsiveness in allergic BALB/c mice?

Zhang Q, Lai K, Xie J, Chen G, Zhong N - Respir. Res. (2009)

Protocol for ovalbumin (OVA) intraperitoneal (i.p.) sensitization and subsequent OVA intranasal (i.n.) challenge. Mice were sensitized by an intraperitoneal injection of 10 μg OVA on days 0, 7 and 14, followed by daily intranasal challenges with 0.2% OVA. OVA-1D-N was challenged on day 28 and airway responsiveness was carried out on day 29 by Penh measurements. OVA-1D-I were challenged on day 28 and airway responsiveness was carried out on day 29 by invasive methods. OVA-3D-N were challenged on days 28, 29, 30 and airway responsiveness was carried out on day 31 by Penh measurements. OVA-3D-I were challenged on days 28, 29, 30 and airway responsiveness was carried out on day 31 by invasive methods.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2719610&req=5

Figure 1: Protocol for ovalbumin (OVA) intraperitoneal (i.p.) sensitization and subsequent OVA intranasal (i.n.) challenge. Mice were sensitized by an intraperitoneal injection of 10 μg OVA on days 0, 7 and 14, followed by daily intranasal challenges with 0.2% OVA. OVA-1D-N was challenged on day 28 and airway responsiveness was carried out on day 29 by Penh measurements. OVA-1D-I were challenged on day 28 and airway responsiveness was carried out on day 29 by invasive methods. OVA-3D-N were challenged on days 28, 29, 30 and airway responsiveness was carried out on day 31 by Penh measurements. OVA-3D-I were challenged on days 28, 29, 30 and airway responsiveness was carried out on day 31 by invasive methods.
Mentions: OVA immunized mice were divided into four groups based on their treatment and measurement of airway responsiveness (see Figure 1).

Bottom Line: Compared with controls, a significant increase in airway responsiveness was shown in the OVA-1D-N group (P < 0.05) but not in the OVA-1D-I group.The invasive measurement is specific to lower airway.Penh measurement (done as a screening procedure), must be confirmed by a direct invasive measurement specific to lower airway in evaluating lower airway responsiveness.

View Article: PubMed Central - HTML - PubMed

Affiliation: State Key Laboratory of Respiratory Disease (Guangzhou Medical University), The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, PR China. Dr.zhang68@yahoo.com

ABSTRACT

Background: Unrestrained plethysmography has been used to monitor bronchoconstriction because of its ease of use and ability to measure airway responsiveness in conscious animals. However, its reliability remains controversial.

Objective: To investigate if unrestrained plethysmography could provide a valid interpretation of airway responsiveness in allergic BALB/c mice.

Methods: Ovalbumin sensitized BALB/c mice were randomized to receive either a single-dose Ovalbumin challenge (OVA-1D group) or a three-dose Ovalbumin challenge (OVA-3D group). The OVA-1D group was further divided into OVA-1D-I (measured invasively, using lung resistance as the index of responsiveness) and OVA-1D-N group (measured non-invasively, using Penh as the index of responsiveness). Similarly the OVA-3D group was divided into OVA-3D-I and OVA-3D-N groups based on the above methods. The control groups were sensitized and challenged with normal saline. Bronchial alveolar lavage fluid was taken and airway histopathology was evaluated for airway inflammation. Nasal responsiveness was tested with histamine challenge.

Results: Compared with controls, a significant increase in airway responsiveness was shown in the OVA-1D-N group (P < 0.05) but not in the OVA-1D-I group. Both OVA-3D-I and OVA-3D-N groups showed higher responsiveness than their controls (P < 0.05). The nasal mucosa was infiltrated by eosinophic cells in all Ovalbumin immunized groups. Sneezing or nasal rubbing in allergic groups appeared more frequent than that in the control groups.

Conclusion: Penh can not be used as a surrogate for airway resistance. The invasive measurement is specific to lower airway. Penh measurement (done as a screening procedure), must be confirmed by a direct invasive measurement specific to lower airway in evaluating lower airway responsiveness.

Show MeSH
Related in: MedlinePlus