Noradrenaline bitartrate monohydrate

Noradrenaline bitartrate monohydrate is an agonist of adrenergic receptors, with Ki values of 330, 56 and 740 nM for α₁, α₂ and β₁ adrenoceptors, respectively [1].

Noradrenaline is a neurotransmitter distributed in both the peripheral and central nervous systems. In the autonomic nervous system, noradrenaline acting at α₁-receptors causes constriction of cutaneous blood vessels. In the central nervous system, noradrenaline found primarily in the locus coeruleus in the brainstem, plays important roles in a variety of physiological activities, such as sleep/wake cycles, attention, orientation, mood and memory [2].

In femoral strips isolated from the untreated dogs, noradrenaline bitartrate monohydrate (5 × 10^-9 ~ 10^-4 M) induced dose-dependent contractions which were inhibited completely by 10^-8 M phenoxybcnzamine administered 40 min previously. In the femoral strips isolated from the ephedrine-treated dogs, contractile responses to noradrenaline bitartrate monohydrate were potentiated at low concentrations (5 × 10^-9 ~ 10^-7 M) but inhibited at high concentrations (5 × 10^-7 ~ 10^-4 M) [3].

References:

[1]. Ramos B P, Arnsten A F. Adrenergic pharmacology and cognition: focus on the prefrontal cortex. Pharmacology & Therapeutics, 2007, 113(3): 523-536.

[2]. Bylund D B, Bylund K C. Norepinephrine. Encyclopedia of the Neurological Sciences (Second Edition), 2014, 3:  638–640.

[3]. Furukawa T, Morishita H. Modifications of responses to adrenergic drugs in arterial strip by treatment in vivo with ephedrine and reserpine. The Japanese Journal of Pharmacology, 1975, 25(4): 441-451.