Adrenal Chromaffin Cell Function under

(1)小鼠离体染色质细胞对[3H]多巴胺的摄取。小鼠的肾上腺被分离，皮质被移除。胶原酶消化肾上腺髓质。分离的嗜铬细胞在含有某种物质的培养基中孵育，这种物质被认为是在应激下分泌的。bardykinin、血管紧张素II、神经紧张素、VIP和p物质抑制[3H]多巴胺的摄取，这些物质被认为是抑制儿茶酚胺的摄取，延长应激下分泌的儿茶酚胺的生物作用。(2)应激对体内[3H]多巴胺和[3H]亮氨酸摄取的影响。小鼠固定应激2 h， [3H]腹腔注射多巴胺，一定时间后对小鼠肾上腺进行放射自显影。应激可抑制多巴胺的摄取，肾上腺去神经可防止这种抑制。这一结果可能表明应激增加了交感神经对肾上腺的活动，抑制了儿茶酚胺的摄取，从而延长了儿茶酚胺的作用。胁迫增加了[3H]亮氨酸的摄取。肾上腺去神经支配抑制摄取。染色质颗粒的成分，如氨基酸，如亮氨酸，在胞吐过程中会丢失。因此，增强的亮氨酸摄取被认为是取代失去的成分。

(1) Uptake of [3H]dopamine in isolated chromaffin cells of mice.The adrenal glands of the mouse were isolated and the cortex was removed. The adrenal medulla was digested by collagenase. Isolated chromaffin cells were incubated in the medium containing certain substance which is considered to be secreted under stress. The uptake of [3H]dopamine was inhibited by bardykinin, angiotensin II, neurotensin, VIP and substance P. These substances are considered to inhibit catecholamine uptake to extend the biological action of catecholamines secreted under stress.(2) Effect of stress on the uptake of [3H]dopamine and [3H]leucine in vivo.Mice were exposed to immobilization stress for 2 h. [3H]dopamine was injected i. p. and after a certain period, the adrenal glands of mice were processed for autoradiography. The uptake of dopamine was inhibited by stress and the inhibition was prevented by adrenal denervation. This result may indicate that stress increased sympathtic nerve activity to the adrenal gland and inhibited catecholamine uptake to extend the action of catecholmaines.The uptake of [3H]leucine was increased by stress. Adrenal denervation inhibited the uptake. Constituents of chromaffin granules such as amino acids like leucine will be lost during exocytosis. Thus the enhancement of leucine uptake is considered to replace the lost constituents.