Stress-induced changes of the noradrenergic transmitter release in adrenals and the influence of substance P

The paper presents results about the role of Substance P (SP) in stressful situations, especially on the spontaneous and nicotine-evoked noradrenaline (3H-NA) outflow in adrenal gland slices. Chronic stress increases the spontaneous as well as the stimulated 3H-NA outflow. SP applied i.p. during stress exposure inhibits the stress-induced elevation of the spontaneous and stimulated 3H-NA outflow. Application of SP direct to the superfusion solution influences the stimulated 3H-NA outflow but it does not change the spontaneous 3H-NA outflow in adrenal gland slices of stressed rats. The data support the hypothesis that SP modulates the transmitter release in adrenals during stressful situations.