[Chromogranin A like immunoreactivity in respiratory tissues of ovalbumin-sensitized guinea pigs].

Chromogranin A like immunoreactivity (CGA-IR) was measured by a specific radioimmunoassay using N-terminal specific antiserum R-0763 in respiratory tissues of guinea pigs. All guinea pig were actively immunized by recurrent Ovalbumin (OA)-inhalation and divided into two groups; one was challenged by OA, and the other inhaled saline as a control. These groups were studied for respiratory resistance and sacrificed for measurement of CGA-IR concentrations in the trachea, major bronchus and lower lung. In the control group, CGA-IR level was 0.4-2 pmol/g wet weight of tissue, and its distribution order was lower lung > trachea > major bronchus. In the OA-challenged group, provocation clearly induced significant elevation of CGA-IR in the trachea and main bronchus coinciding with elevation of respiratory resistance. In the lower lung, on the other hand, the increase in CGA-IR was not significant. These results suggest that experimental immediate asthmatic response (IAR) possibly acts as a stressor to the sympathetic nervous systems in guinea pig air-ways.