Noradrenalin
A catecholamine, a carrier of noradrenergic nerves in the CNS, which can be released by sympathetic nerve endings and from the adrenal medulla and activates adrenergic and beta receptors. In the heart, a positive inotropic, chronotropic, dromotropic, bathmotropic effect is achieved by Noradrenalin via beta1 receptors.
Noradrenalin is on the one hand a carrier substance of the postganglionic synapses of the sympathetic nervous system and has the same effect as adrenalin and on the other hand a hormone from the adrenal medulla. It acts mainly on the arterioles and, by activating so-called adrenoreceptors, leads to a narrowing of these vessels and consequently to an increase in blood pressure.
Noradrenalin is one of the most important messengers of the central nervous system and the sympathetic nervous system. Heart, circulation, respiration, metabolism and gastrointestinal functions are controlled by the vegetative nervous system. This explains why some people react to stress with their stomach and intestines. Like adrenaline, noradrenaline increases blood pressure, but does not change the minute volume and even lowers the pulse rate.
Noradrenalin centrally controls mental and psychological stress adaptation. It also increases motivation, attention and mental motivation. In the short term, however, noradrenalin inhibits the immune response. Therefore, inflammation may occur under permanent stress. Permanent stress can also lead to norepinephrine deficiency, resulting in impaired mental performance and depression.