Mechanism of triazolo-benzodiazepine and benzodiazepine action in anxiety
and depression: behavioral studies with concomitant in vivo CA1 hippocampal
norepinephrine and serotonin release detection in the behaving animal
by
Broderick PA, Hope O, Jeannot P
Department of Physiology and Pharmacology,
City University of New York
Medical School, NY, USA.
102414.1200@Compuserve.com
Prog Neuropsychopharmacol Biol Psychiatry 1998 Feb; 22(2):353-86
ABSTRACT
1. Real time, in vivo microvoltammetric studies were performed, using
miniature carbon-based sensors, to concurrently detect norepinephrine (NE)
release and serotonin (5-HT) release, in 2 separate electrochemical signals,
within CA1 region of hippocampus in the freely moving and behaving, male,
Sprague Dawley laboratory rat. 2. Concurrently, four parameters of open-field
behavior, i.e. Ambulations, Rearing, Fine Movements and Central Ambulatory
behavior (a measure of anxiety reduction behavior), were assayed by infrared
photobeam detection. 3. Time course studies showed that the mechanism of action
of the triazolobenzodiazepine (TBZD), adinazolam, (Deracyn) is dramatically
different from that of the classical benzodiazepine (BZD), diazepam (Valium,
i.e., adinazolam increased, whereas diazepam decreased, 5-HT release within CA1
region of hippocampus in the freely moving and behaving rat. 4. Adinazolam
initially increased NE release and then decreased NE release in CA1 region of
hippocampus in the freely moving and behaving rat whereas diazepam only
decreased the electrochemical signal for NE; the decrease in NE produced by
adinazolam was greater than the decrease in NE release produced by diazepam. 5.
The Behavioral Activity Patterns, derived from same animal controls,
simultaneously with detection of in vivo microvoltammetric signals for NE
release and 5-HT release, showed that the BZD, diazepam, exhibited more potent
sedative properties than did the TBZD adinazolam. 6. Hippocampal 5-HT and NE
release effects of the TBZD, adinazolam, concomitant with behavioral effects
lends explanation to the dual anxiolytic/antidepressant properties of the TBZDs.
SSRIs
Anxiety
Buspirone
Sedatives
Ipsapirone
Clonazepam
Ondansetron
Noradrenaline
GABAergic drugs
Benzodiazepines
Sedative hypnotics
Virtual reality exposure
Anxiolytics/antidepressants
Adinazolam (Deracyn) : pharmacokinetics