Detection of mediator-induced airway constriction by barometric plethysmography in mice.
The barometric method has recently been employed to detect airway constriction in small animals. This study was designed to evaluate the barometric method to detect mediator-induced central and peripheral airway constriction in BALB/c mice. First, the central airway constrictor carbachol and the peripheral airway constrictor histamine were employed to induce airway constriction, which was detected by both the conventional body plethysmography and the barometric method in anesthetized mice. Second, bronchoconstriction induced by aerosolized carbachol or other mediators was detected with the barometric plethysmography in conscious, unrestrained mice. Carbachol inhalation caused about four-fold increase in pulmonary resistance (RL) and about two-fold increase in enhanced pause (Penh) in anesthetized mice. In contrast, in the same preparation, histamine aerosol induced a decrease in dynamic compliance (Cdyn), with no alteration in RL or Penh. In awake mice, carbachol and methacholine caused increases in Penh, frequency, and tidal volume (VT). On the other hand, histamine, histamine + bradykinin, and prostaglandin-D2 did not alter Penh but decreased VT in conscious mice. These data suggest that there was no sufficient evidence to indicate that Penh could be a good indicator of bronchoconstriction for the whole airways.
Lai
Yih-Loong
YL
Departments of Physiology, National Taiwan University, College of Medicine, Taipei 100, Taiwan.
Lee
Ken-Chung
KC
Kuo
Ping-Hung
PH
D000399:Air Pressure; D000403:Airway Resistance / Q000502:physiology; D000758:Anesthesia; D000818:Animals; D001920:Bradykinin / Q000494:pharmacology; D002217:Carbachol / Q000494:pharmacology; D003251:Constriction, Pathologic / Q000175:diagnosis*; D006632:Histamine / Q000494:pharmacology; D008170:Lung Compliance / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D018721:Muscarinic Agonists / Q000494:pharmacology; D010991:Plethysmography / Q000379:methods*; D010993:Plethysmography, Whole Body; D015656:Respiratory Mechanics / Q000187:drug effects / Q000502:physiology; D013990:Tidal Volume / Q000502:physiology
D018721:Muscarinic Agonists; D006632:Histamine; D002217:Carbachol; D001920:Bradykinin