Objective: To study the changes of guanylin in asthmatic guinea pig models.
Methods: Male guinea pigs were randomly divided into two groups: the control (n = 6) and the asthma group (n = 10). The levels of guanylin in plasma, BALF and lung tissue were measured by RIA kit. The mean thickness of airway wall and glands was determined by contour tracing, using a digitizing pad and microcomputer.
Results: The levels of guanylin in plasma and lung tissue from the asthma group were 56% and 183% higher than those of the control (P < 0.01). Concentrations of guanylin in BALF from the control were below the detection level in 4 guinea pigs, and 1.7 pg/ml and 1.6 pg/ml in two, respectively. The level of guanylin in BALF from asthma group was (3.1 +/- 1.2) pg/ml. The level of guanylin in the lung tissue correlated with that in plasma and BALF (r = 0.72, P < 0.01, r = 0.61, P < 0.05, respectively). The level of guanylin in plasma did not correlate with those of BALF (r = 0.32, P > 0.05). The mean thickness of airway wall and glands in asthma group were 86% and 87% greater than those of the control respectively (P < 0.01). The level of guanylin in lung tissue correlated with the thickness of glands (r = 0.95, P < 0.01).
Conclusions: In the guinea pig model of asthma, guanylin in plasma, BALF and lung tissue were increased, indicating that it may play a role in the mechanism of airway hypersecretion in asthma.