Effect of systemic nicotine on mucus secretion from tracheal submucosal glands and on cardiovascular, pulmonary, and hematologic variables.
Atslēgvārdi
Abstrakts
To investigate effects of systemic nicotine on mucus secretion from tracheal submucosal glands we anesthetized 13 ferrets (5 male, 8 female; average weight 1138 +/- 469 g, mean +/- SD) with pentobarbital (initial dose, 62 +/- 26, total dose, 90 +/- 26 mg/kg), cannulated the jugular vein for i.v. application of infusions and drugs and cannulated the femoral artery for determination of blood pressure, heart rate, blood cells, and blood gases. We opened the thorax, cannulated the trachea 1 cm above the carina and ventilated the lungs through the lower airways with a Harvard respirator. We placed an electromagnetic flow probe around the ascending aorta for measurement of cardiac output. We measured transpulmonary pressure as tracheal pressure with a strain gauge transducer. We created an isolated segment of trachea between the larynx and the tracheal cannula. We perfused the segment with medium M-199 containing 30 microCi/ml Na(2)35SO4 (35S) and we injected 100 microCi 35S intravenously. After 90 min we drained the radioactive solution from the luminal side and replaced it with nonradioactive medium which we collected at 5-min intervals for determination of nondialyzable radioactivity. At 25 min we injected nicotine sulfate (5 x 10(-7)-10(-5) M/kg) and continued to collect the perfusate every 5 min. Systemic nicotine had profound effects on circulatory and ventilatory variables and on gland secretion. Initial hypertension was followed by bradycardia and a fall in blood pressure and cardiac output.(ABSTRACT TRUNCATED AT 250 WORDS)