Bronchoconstriction induced by increasing airway temperature in ovalbumin-sensitized rats: role of tachykinins

This study was carried out to determine the effect of allergic inflammation on the airway response to increasing airway temperature. Our results showed the following: 1) In Brown-Norway rats actively sensitized by ovalbumin (Ova), isocapnic hyperventilation with humidified warm air (HWA) for 2 min raised tracheal temperature (Ttr) from 33.4 ± 0.6°C to 40.6 ± 0.1°C, which induced an immediate and sustained (>10 min) increase in total pulmonary resistance (Rl) from 0.128 ± 0.004 to 0.212 ± 0.013 cmH2O·ml−1·s ( n = 6, P < 0.01). In sharp contrast, the HWA challenge caused the same increase in Ttrbut did not generate any increase in Rl in control rats. 2) The increase in Rl in sensitized rats was reproducible when the same HWA challenge was repeated 60–90 min later. 3) This bronchoconstrictive effect was temperature dependent: a slightly smaller increase in peak Ttr(39.6 ± 0.2°C) generated a significant but smaller increase in Rl in sensitized rats. 4) The HWA-induced bronchoconstriction was not generated by the humidity delivered by the HWA challenge alone, because the same water content delivered by saline aerosol at room temperature had no effect. 5) The HWA-evoked increase in Rl in sensitized rats was not blocked by atropine but was completely prevented by pretreatment either with a combination of neurokinin (NK)-1 and NK-2 antagonists or with formoterol, a β2agonist, before the HWA challenge. This study showed that increasing airway temperature evoked a pronounced and reversible increase in airway resistance in sensitized rats and that tachykinins released from the vagal bronchopulmonary C-fiber endings were primarily responsible.

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Effects of elastase-induced emphysema on airway responsiveness to methacholine in rats

Journal of Applied Physiology ◽

10.1152/jappl.1989.66.2.606 ◽

1989 ◽

Vol 66 (2) ◽

pp. 606-612 ◽

Cited By ~ 47

Author(s):

S. Bellofiore ◽

D. H. Eidelman ◽

P. T. Macklem ◽

J. G. Martin

Keyword(s):

Lung Volume ◽

Brown Norway ◽

Pulmonary Mechanics ◽

Maximum Increase ◽

Before And After ◽

Airway Response ◽

Residual Capacity ◽

Airway Responses ◽

Norway Rats ◽

Concentration Response Curve

We examined the effects of elastase-induced emphysema on lung volumes, pulmonary mechanics, and airway responses to inhaled methacholine (MCh) of nine male Brown Norway rats. Measurements were made before and weekly for 4 wk after elastase in five rats. In four rats measurements were made before and at 3 wk after elastase; in these same animals the effects of changes in end-expiratory lung volume on the airway responses to MCh were evaluated before and after elastase. Airway responses were determined from peak pulmonary resistance (RL) calculated after 30-s aerosolizations of saline and doubling concentrations of MCh from 1 to 64 mg/ml. Porcine pancreatic elastase (1 IU/g) was administered intratracheally. Before elastase RL rose from 0.20 +/- 0.02 cmH2O.ml-1.s (mean +/- SE; n = 9) to 0.57 +/- 0.06 after MCh (64 mg/ml). A plateau was observed in the concentration-response curve. Static compliance and the maximum increase in RL (delta RL64) were significantly correlated (r = 0.799, P less than 0.01). Three weeks after elastase the maximal airway response to MCh was enhanced and no plateau was observed; delta RL64 was 0.78 +/- 0.07 cmH2O.ml-1.s, significantly higher than control delta RL64 (0.36 +/- 0.7, P less than 0.05). Before elastase, increase of end-expiratory lung volume to functional residual capacity + 1.56 ml (+/- 0.08 ml) significantly reduced RL at 64 mg MCh/ml from 0.62 +/- 0.05 cmH2O.ml-1.s to 0.50 +/- 0.03, P less than 0.05.(ABSTRACT TRUNCATED AT 250 WORDS)

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Strain dependence of the airway response to dry-gas hyperpnea challenge in the rat

Journal of Applied Physiology ◽

10.1152/jappl.1999.86.1.152 ◽

1999 ◽

Vol 86 (1) ◽

pp. 152-158 ◽

Cited By ~ 4

Author(s):

X. X. Yang ◽

W. S. Powell ◽

L. J. Xu ◽

J. G. Martin

Keyword(s):

Tidal Volume ◽

Receptor Antagonist ◽

Spontaneous Breathing ◽

Brown Norway ◽

Pulmonary Resistance ◽

Strain Dependence ◽

Fischer 344 ◽

Airway Response ◽

Airway Responses ◽

Strain Dependent

The aim of the study was to investigate strain dependence and mechanisms of airway responses to dry-gas hyperpnea challenge in the rat. We studied responses in a strain that is hyperresponsive to methacholine, Fischer 344 (F-344); in two normoresponsive strains, Lewis and ACI; and in an atopic but normoresponsive strain, Brown Norway (BN). We examined the effects of a neurokinin (NK) 1-receptor (CP-99994), an NK2-receptor (SR-48968), and a leukotriene D4(LTD4)-receptor antagonist (pranlukast) on responses to hyperpnea challenge in BN rats. The animals were ventilated with a tidal volume of 8 ml/kg and a frequency of 150 breaths/min with either a dry or humidified mixture of 5% CO2-95% O2 for 5 min for hyperpnea challenge, whereas responses to challenge were measured during spontaneous breathing. Pulmonary resistance increased after dry-gas challenge in BN and ACI but not in F-344 and Lewis rats. CP-99994, SR-48968, and pranlukast significantly attenuated the increase in pulmonary resistance after dry-gas challenge. There were no significant differences in responsiveness to airway challenge with LTD4 among the BN, F-344 and ACI rats. We conclude that responses to dry-gas hyperpnea challenge are strain dependent in rats and are mediated by NKs and LTD4.

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Ovalbumin sensitizes vagal pulmonary C-fiber afferents in Brown Norway rats

Journal of Applied Physiology ◽

10.1152/japplphysiol.01099.2007 ◽

2008 ◽

Vol 105 (2) ◽

pp. 611-620 ◽

Cited By ~ 15

Author(s):

Y. L. Kuo ◽

C. J. Lai

Keyword(s):

Airway Hyperreactivity ◽

Right Atrial ◽

Brown Norway ◽

Saline Control ◽

C Fibers ◽

Open Chest ◽

C Fiber ◽

Lung Resistance ◽

Total Lung Resistance ◽

Norway Rats

Sensitization of vagal lung C fibers has been postulated to contribute to the development of asthma, but support for this notion is still lacking. We investigated the characteristics and function of pulmonary C fibers (PCFs) in ovalbumin (OVA)-sensitized Brown Norway rats, an established animal model of asthma. Rats were sensitized with intraperitoneal injection of OVA or were treated with saline (control). In study 1, with the use of open-chest and artificially ventilated rats, inhalation of 5% OVA aerosol evoked an augmented increase in total lung resistance in the OVA-sensitized rats, compared with the control rats. Bilateral vagotomy or subcutaneous pretreatment with a high-dose of capsaicin for blocking of C-fiber function equally attenuated this augmented total lung resistance response, suggesting the involvement of PCFs. In study 2, with the use of anesthetized, spontaneously breathing rats, right atrial injection of capsaicin (1 μg/kg; a PCF stimulant) evoked an augmented apneic response in the OVA-sensitized rats, compared with the control rats. In study 3, with the use of open-chest, paralyzed, and artificially ventilated rats, the afferent PCF responses to right atrial injection of capsaicin (0.5 and 1.0 μg/kg), phenylbiguanide (8 μg/kg; a PCF stimulant), or adenosine (0.2 mg/kg; a PCF stimulant) were enhanced in the OVA-sensitized rats, compared with the control rats. However, the baseline activities of PCFs and their afferent responses to mechanical stimulation by lung hyperinflation in the OVA-sensitized and control rats were comparable. Our results suggested that OVA-sensitized Brown Norway rats possess sensitized vagal PCFs, which may participate in the development of the airway hyperreactivity observed in these animals.

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Effects of salbutamol and Ro-20-1724 on airway and parenchymal mechanics in rats

Journal of Applied Physiology ◽

10.1152/jappl.1999.87.4.1373 ◽

1999 ◽

Vol 87 (4) ◽

pp. 1373-1380 ◽

Cited By ~ 17

Author(s):

Ferenc Peták ◽

Janet L. Wale ◽

Peter D. Sly

Keyword(s):

Steady State ◽

Airway Resistance ◽

Brown Norway ◽

Wave Tube ◽

Norway Rat ◽

Airway Caliber ◽

Brown Norway Rat ◽

Phosphodiesterase Type ◽

Induced Changes ◽

Norway Rats

We investigated the effects of a selective β2-agonist, salbutamol, and of phosphodiesterase type 4 inhibition with 4-(3-butoxy-4-methoxy benzyl)-2-imidazolidinone (Ro-20-1724) on the airway and parenchymal mechanics during steady-state constriction induced by MCh administered as an aerosol or intravenously (iv). The wave-tube technique was used to measure the lung input impedance (Zl) between 0.5 and 20 Hz in 31 anesthetized, paralyzed, open-chest adult Brown Norway rats. To separate the airway and parenchymal responses, a model containing an airway resistance (Raw) and inertance (Iaw), and a parenchymal damping (G) and elastance (H), was fitted to Zl spectra under control conditions, during steady-state constriction, and after either salbutamol or Ro-20-1724 delivery. In the Brown Norway rat, the response to iv MCh infusion was seen in Raw and G, whereas continuous aerosolized MCh challenge produced increases in G and H only. Both salbutamol, administered either as an aerosol or iv, and Ro-20-1724 significantly reversed the increases in Raw and G when MCh was administered iv. During the MCh aerosol challenge, Ro-20-1724 significantly reversed the increases in G and H, whereas salbutamol had no effect. These results suggest that, after MCh-induced changes in lung function, salbutamol increases the airway caliber. Ro-20-1724 is effective in reversing the airway narrowings, and it may also decrease the parenchymal constriction.

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Dose-dependent inhibition of allergic inflammation and bronchial hyperresponsiveness by budesonide in ovalbumin-sensitised Brown-Norway rats

Pulmonary Pharmacology & Therapeutics ◽

10.1016/j.pupt.2007.01.001 ◽

2008 ◽

Vol 21 (1) ◽

pp. 98-104 ◽

Cited By ~ 4

Author(s):

Sum Yee Leung ◽

Alison S. Williams ◽

Puneeta Nath ◽

Q. Thai Dinh ◽

Timothy Oates ◽

...

Keyword(s):

Bronchial Hyperresponsiveness ◽

Allergic Inflammation ◽

Brown Norway ◽

Dependent Inhibition ◽

Dose Dependent Inhibition ◽

Dose Dependent ◽

Norway Rats

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Role of sodium silicate in induction of scleroderma-related autoantibodies in brown Norway rats through oral and subcutaneous administration

Rheumatology International ◽

10.1007/s00296-009-1327-3 ◽

2010 ◽

Vol 31 (5) ◽

pp. 611-615 ◽

Cited By ~ 7

Author(s):

Sultan M. Al-Mogairen

Keyword(s):

Sodium Silicate ◽

Subcutaneous Administration ◽

Brown Norway ◽

Norway Rats

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Comparison of upper and lower airway responses of two sensitized rat strains to inhaled antigen

Journal of Applied Physiology ◽

10.1152/jappl.1992.73.4.1608 ◽

1992 ◽

Vol 73 (4) ◽

pp. 1608-1613 ◽

Cited By ~ 6

Author(s):

L. J. Xu ◽

S. Sapienza ◽

T. Du ◽

S. Waserman ◽

J. G. Martin

Keyword(s):

Upper Airway ◽

Brown Norway ◽

Lower Airway ◽

Sprague Dawley ◽

Pulmonary Resistance ◽

Upper Airways ◽

Tracheal Pressure ◽

Airway Response ◽

Airway Responses ◽

Inbred Rat

The purpose of the study was to investigate the relationships between upper airways responses and pulmonary responses of two strains of highly inbred rats to inhaled antigen. To do this we measured the upper and lower airways resistance for 60 min after challenge of Brown-Norway rats (BN; n = 13) and an inbred rat strain (MF; n = 11), derived from Sprague-Dawley, with aerosolized ovalbumin (OA). Rats were actively sensitized with OA (1 mg sc) using Bordetella pertussis as an adjuvant. Two weeks later the animals were anesthetized and challenged. Tracheal pressure, esophageal pressure, and airflow were measured, from which total pulmonary resistance was partitioned into upper airway and lower pulmonary resistance (RL). The peak upper airway response to inhaled OA was similar in BN (1.89 +/- 0.66 cmH2O.ml-1.s; n = 7) and MF (2.85 +/- 0.68 cmH2O.ml-1.s; n = 6). The lower airway response to OA challenge was substantially greater in BN, and RL changed from 0.07 +/- 0.01 to 0.34 +/- 0.13 (n = 6; P < 0.05). The MF did not have any significant increase in RL after challenge; the baseline RL was 0.12 +/- 0.02 and only reached a peak value of 0.15 +/- 0.05 (n = 5; P = NS). Lower airway responsiveness of BN (n = 10) to serotonin, an important mediator early allergic airway responses, was similar to MF (n = 7).(ABSTRACT TRUNCATED AT 250 WORDS)

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An ultrastructural study on the role of Kupffer cells in the process of infection by Plasmodium berghei sporozoites in rats

Parasitology ◽

10.1017/s003118200005040x ◽

1983 ◽

Vol 86 (2) ◽

pp. 231-242 ◽

Cited By ~ 73

Author(s):

J. F. G. M. Meis ◽

J. P. Verhave ◽

P. H. K. Jap ◽

J. H. E. Th. Meuwissen

Keyword(s):

Kupffer Cells ◽

Plasmodium Berghei ◽

Brown Norway ◽

Liver Sinusoids ◽

Transmission Electron ◽

Space Of Disse ◽

Rat Livers ◽

Norway Rats

SUMMARYThe interactions in vivo between Plasmodium berghei sporozoites and Kupffer cells in rat livers were studied by transmission electron microscopy. By 10 and 15 min after inoculation, sporozoites were both free in the liver sinusoids and inside endocytotic vacuoles of the Kupffer cells. The latter cells were very active in phagocytosing sporozoites, bacteria and red blood cells. The sporozoites retained their integrity inside the endocytotic vacuoles and no signs of lysosomal digestion were observed. Sporozoites seen within endocytotic vacuoles 1 h after inoculation were still morphologically intact, although bristle-coated vesicles fused with the vacuole membrane. Evidence is presented which suggests that Kupffer cells transport sporozoites towards the space of Disse and adjacent hepatocytes. No sporozoites were seen to penetrate an endothelial cell or its narrow fenestrae. It is proposed that Kupffer cell passage, rather than gaps in the sinusoidal lining, represents the normal route that sporozoites take to circumvent the endothelial barrier. The localization of exo-erythrocytic forms was made easier by the use of Brown Norway rats in which many more parasites develop than in the Wistar rats. The distribution pattern of the parasites was found to be mainly around the ‘periportal’ zones of the acini of liver tissue.

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