Harman- 13 C 2 , 15 N

Harman- 13 C 2, 15 N is 13 C and 15 N labeled Harmane. Harmane is a benzodiazepine receptor inhibitor ( IC₅₀ =7 μM), with IC₅₀ values for mACh, Opioid Receptor, MAO-A/B, and α2-adrenergic receptor of 24 μM, 2.8 μM, 0.5 μM, 5 μM, and 18 μM, respectively. Harmane also inhibits haloperidol and serotonin, with IC₅₀ values of 163 μM and 101 μM, respectively. Harmane inhibits the I1 imidazoline receptor ( IC₅₀ =30 nM) to reduce blood pressure and has antidepressant, anti-anxiety, anticonvulsant, and analgesic effects. Harmane inhibits dopamine biosynthesis by decreasing tyrosine hydroxylase (TH) activity and enhancing L-DOPA-induced cytotoxicity in PC12 cells. Additionally, Harmane can increase the mutagenic effect induced by 2-acetylaminofluorene (AAF) ^{[1] [2] [3] [4] [5] [6]}.

References:
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[2]. Musgrave IF, et, al. Harmane produces hypotension following microinjection into the RVLM: possible role of I(1)-imidazoline receptors. Br J Pharmacol. 2000 Mar;129(6):1057-9.
[3]. W E Müller, et al. On the neuropharmacology of harmane and other beta-carbolines. Pharmacol Biochem Behav. 1981 May;14(5):693-9.
[4]. Glover V, et, al. β-Carbolines as selective monoamine oxidase inhibitors:In vivo implications
[5]. E D Louis, et al. Harmane induces anxiolysis and antidepressant-like effects in rats. Ann N Y Acad Sci. 2005 Aug 9;65(3):391-6.
[6]. Umezawa K, et, al. Comutagenic effect of norharman and harman with 2-acetylaminofluorene derivatives. Proc Natl Acad Sci U S A. 1978 Feb;75(2):928-30.
[7]. Yoo Jung Yang, et al. Effects of harman and norharman on dopamine biosynthesis and L-DOPA-induced cytotoxicity in PC12 cells. Eur J Pharmacol. 2008 Jun 10;587(1-3):57-64.