Etazolate Explained

Etazolate (SQ-20,009, EHT-0202) is an anxiolytic drug which is a pyrazolopyridine derivative and has unique pharmacological properties.^{[1] [2] [3]} It acts as a positive allosteric modulator of the GABA_A receptor at the barbiturate binding site,^{[4] [5] [6] [7]} as an adenosine antagonist of the A₁ and A₂ subtypes,^[8] and as a phosphodiesterase inhibitor selective for the PDE4 isoform.^{[9] [10] [11]} It is currently in clinical trials for the treatment of Alzheimer's disease.^[12]

See also

• Cartazolate
• ICI-190,622
• Tracazolate

Notes and References

1. Book: Hall JA, Morton I . Concise dictionary of pharmacological agents: properties and synonyms . Kluwer Academic . 1999 . 0-7514-0499-3 .
2. Williams M . Anxioselective anxiolytics . Journal of Medicinal Chemistry . 26 . 5 . 619–628 . May 1983 . 6132997 . 10.1021/jm00359a001 .
3. Williams M, Risley EA . Enhancement of the binding of 3H-diazepam to rat brain membranes in vitro by SQ 20009, A novel anxiolytic, gamma-aminobutyric acid (GABA) and muscimol . Life Sciences . 24 . 9 . 833–841 . February 1979 . 449623 . 10.1016/0024-3205(79)90367-9 .
4. Zezula J, Slany A, Sieghart W . Interaction of allosteric ligands with GABAA receptors containing one, two, or three different subunits . European Journal of Pharmacology . 301 . 1–3 . 207–214 . April 1996 . 8773466 . 10.1016/0014-2999(96)00066-0 .
5. Book: Davies MF . The Pharmacology of the Gamma-Aminobutyric Acid System. Remington G, Baskys A . Brain mechanisms and psychotropic drugs . CRC Press . Boca Raton . 1996 . 0-8493-8386-2 . https://books.google.com/books?id=SPEIn0S6aK8C&q=etazolate&pg=PA109.
6. Book: Olsen RW, Gordey M . GABAA Receptor Chloride Ion Channels . Mishina M, Kurachi Y . Pharmacology of ionic channel function: activators and inhibitors . Handbook of Experimental Pharmacology . Springer . Berlin . 2000 . 147 . 499–517 . 3-540-66127-1 . https://books.google.com/books?id=t7i4yNiXiFMC&q=etazolate&pg=PA503 . 10.1007/978-3-642-57083-4_19 .
7. Book: Olsen RW . GABA-Drug Interactions . Jucker E . Progress in Drug Research . 31 . Birkhauser . Boston . 1987 . 526 . 3-7643-1837-6 . https://books.google.com/books?id=gx6dwxmlQwMC&q=etazolate&pg=PA225.
8. Williams M, Jarvis MF . Adenosine antagonists as potential therapeutic agents . Pharmacology, Biochemistry, and Behavior . 29 . 2 . 433–441 . February 1988 . 3283781 . 10.1016/0091-3057(88)90182-7 . 35635747 .
9. Chasin M, Harris DN, Phillips MB, Hess SM . 1-Ethyl-4-(isopropylidenehydrazino)-1H-pyrazolo-(3,4-b)-pyridine-5-carboxylic acid, ethyl ester, hydrochloride (SQ 20009)--a potent new inhibitor of cyclic 3',5'-nucleotide phosphodiesterases . Biochemical Pharmacology . 21 . 18 . 2443–2450 . September 1972 . 4345859 . 10.1016/0006-2952(72)90414-5 .
10. Wang P, Myers JG, Wu P, Cheewatrakoolpong B, Egan RW, Billah MM . Expression, purification, and characterization of human cAMP-specific phosphodiesterase (PDE4) subtypes A, B, C, and D . Biochemical and Biophysical Research Communications . 234 . 2 . 320–324 . May 1997 . 9177268 . 10.1006/bbrc.1997.6636 .
11. Book: Daniel JL . Platelet signalling; cAMP and cGMP . Gresele P . Platelets in thrombotic and non-thrombotic disorders: pathophysiology, pharmacology and therapeutics . Cambridge University Press . Cambridge, UK . 2002 . 0-521-80261-X . https://books.google.com/books?id=W1O-rgRYSdEC&q=etazolate+%22PDE4%22&pg=PA294.
12. Web site: EHT 0202 . Pipeline . ExonHit . https://web.archive.org/web/20110111115443/http://www.exonhit.com/therapeutics/pipeline#eht_0202 . 2011-01-11 . dead .