The effect of isobaric hypoxia on the density of subtypes of ? and ? adrenoceptors in rat lung / 中国病理生理杂志

ABSTRACT

Rats were kept in isobaric hypoxic chamber (O_2=10%)for ? , ? and 4 weeks(6h/day, 6days/week). The lung adrenoceptors were measured by radioligand bindingtechnique. Results showed that the ? adrenoceptor increased at 1st week of hypoxia and de-creased significantly at 2nd and 4th weeks of hypoxia. The change of ?_2 adrenoceptor wasconsistant with that of total ? adrenoceptor but the decrease was more significant. By con-trast, the ?_2 adrenoceptor increased significantly all the time. No change of Kd valuewas found in this study. The data indicated that the changes of adrenoceptors induced byhypoxia caused the domination of pulmonary vasoconstriction which may play a role inthe developement of hypoxic pulmonary hypertension.