Cervical dislocation of mice induces rapid accumulation of platelet serotonin in the lung

Abstract

As much as 3-8 micrograms/g wet weight of serotonin (5-hydroxytryptamine, 5HT) has been detected in mouse lung 10 sec after the animal was sacrificed by cervical dislocation. Perfusion of the lung was carried out to determine where the majority of 5HT was located. Of the total 5HT, 84.3% was measured in the perfusate in which 90-98% was recovered in the platelet-rich fraction. When lungs were dissected from mice without cervical dislocation, either after instantaneous killing by irradiation with high power microwaves or under anesthesia, 5HT in the lung was 0.40-1.60 microgram/g tissue. These results show that cervical dislocation induces the entrapment of platelets in the pulmonary capillaries within 10 sec. The pulmonary accumulation of 5HT induced by cervical dislocation was approximately 50% inhibited by both prazosin and yohimbine, suggesting that the alpha-adrenergic receptor plays some part in the process. Norepinephrine but not isoproterenol augmented by 180% the response of pulmonary 5HT to cervical dislocation.