Olanzapine plus fluoxetine treatment increases Nt-3 protein levels in the rat prefrontal cortex

AbstractEvidence is emerging for a role for neurotrophins in the treatment of mood disorders. In this study, we evaluated the effects of chronic administration of fluoxetine, olanzapine and the combination of fluoxetine/olanzapine on the brain-derived-neurotrophic factor (BDNF), nerve growth factor (NGF), and neurotrophin-3 (NT-3) in the rat brain. Wistar rats received daily injections of olanzapine (3 or 6mg/kg) and/or fluoxetine (12.5 or 25mg/kg) for 28 days, and we evaluated for BDNF, NGF and NT-3 protein levels in the prefrontal cortex, hippocampus and amygdala. Our results showed that treatment with fluoxetine and olanzapine alone or in combination did not alter BDNF in the prefrontal cortex (p=0.37), hippocampus (p=0.98) and amygdala (p=0.57) or NGF protein levels in the prefrontal cortex (p=0.72), hippocampus (p=0.23) and amygdala (p=0.64), but NT-3 protein levels were increased by olanzapine 6mg/kg/fluoxetine 25mg/kg combination in the prefrontal cortex (p=0.03), in the hippocampus (p=0.83) and amygdala (p=0.88) NT-3 protein levels did not alter. Finally, these findings further support the hypothesis that NT-3 could be involved in the effect of treatment with antipsychotic and antidepressant combination in mood disorders

Manipulation of BDNF Signaling Modifies the Experience-Dependent Plasticity Induced by Pure Tone Exposure during the Critical Period in the Primary Auditory Cortex

Sensory experience powerfully shapes cortical sensory representations during an early developmental "critical period" of plasticity. In the rat primary auditory cortex (A1), the experience-dependent plasticity is exemplified by significant, long-lasting d

Trypanosoma brucei brucei: Biochemical characterization of ecto-nucleoside triphosphate diphosphohydrolase activities

in this work we describe the ability of living cells of Trypanosoma brucei brucei to hydrolyze extracellular ATP. In these intact parasites there was a low level of ATP hydrolysis in the absence of any divalent metal (4.72 +/- 0.51 nmol Pi x 10(-7) cells x h(-1)). The ATP hydrolysis was stimulated by MgCl2 and the Mg-dependent ecto-ATPase activity was 27.15 +/- 2.91 nmol Pi x 10(-7) cells x h(-1). This stimulatory activity was also observed when MgCl2 was replaced by MnCl2. CaCl2 and ZnCl2 were also able to stimulate the ATPase activity, although less than MgCl2. The apparent K-m for ATP was 0.61 mM. This ecto-ATPase activity was insensitive to inhibitors of other ATPase and phosphatase activities. To confirm that this Mg-dependent ATPase activity is an ecto-ATPase activity, we used an impermeable inhibitor, DIDS (4, 4'-diisothiocyanostylbene 2'-2'-disulfonic acid), as well as suramin, an antagonist of P-2 purinoreceptors and inhibitor of some ecto-ATPases. These two reagents inhibited the Mg2+-dependent ATPase activity in a dose-dependent manner. Living cells sequentially hydrolyzed the ATP molecule generating ADP, AMP and adenosine, and supplementation of the culture medium with ATP was able to sustain the proliferation of T brucei brucei as well as adenosine supplementation. Furthermore, the E-NTPDase activity of T brucei brucei is modulated by the availability of purines in the medium. These results indicate that this surface enzyme may play a role in the salvage of purines from the extracellular medium in T brucei brucei. (c) 2006 Elsevier Inc. All rights reserved.115431532

SHORT COMMUNICATION - A New Serovar and a New Serological Variant Belonging to Salmonella enterica Subspecies diarizonae

Description of a new serovar (S. IIIb 16:k:e,n,x,z15) and a new serological variant (S. IIIb 42:z10:e,n,x,z15:z60 ) belonging to the genus Salmonella isolated from stool specimens of Brazilian snakes (Crotalus durissus )