16 research outputs found
Role of 5-HT 1A receptors in antidepressant-like effect of dichloromethane fraction of Kielmeyera coriacea in rats subjected to the forced swim test
Objective : We examined the involvement of 5-HT neurotransmission on
the antidepressant-like effect of the dichloromethane (DcM) fraction of
an extract from Kielmeyera coriacea stems. Materials and Methods :
Male Wistar rats treated chronically (45 days, gavage) with the DcM
fraction received an intradorsal raphe nucleus (DRN) microinjection of
saline or 5-HT 1A receptor ligands and were evaluated in the forced
swimming test (FST) and in the open-field test (OFT). Results : The
DcM fraction (5.0 mg/kg) reduced immobility time in the FST without
altering locomotion in the OFT. IntraDRN microinjection of the 5-HT 1A
receptor agonist, (+)-8-OH-DPAT (0.10; 0.20 or 0.33 μg) increased
immobility time and reduced locomotion at the higher dose whereas the
5-HT1A antagonists, (-)-pindolol (0.10; 0.20 or 0.40 μg) or
WAY100635 (0.11; 0.22 or 0.43 μg) did not produce any effect in
the behavioral tests. IntraDRN (+)-8-OH-DPAT (0.20 or 0.33 μg) in
rats treated with the DcM fraction (5.0 mg/kg) blocked the changes in
the immobility time or in locomotion produced by each drug. Intra-DRN
(-)-pindolol (0.10 μg) or WAY100635 (0.43 μg) in rats treated
with a subactive dose of the DcM fraction (4.0 mg/kg) synergistically
reduced immobility time in the FST. Conclusion : The DcM fraction of
Kielmeyera coriacea produced an antidepressant-like effect in the FST
and interacted with 5-HT 1A receptor ligands. Activation of 5-HT 1A
receptors into DRN by (+) 8-OH-DPAT produced detectable changes in the
FST or in the OFT
Classification of commercial catuaba samples by NMR, HPLC and chemometrics
For over a century, Catuaba has been used in Brazilian folk medicine as an aphrodisiac even though the identity of the plant material employed is often uncertain. The species recommended by the Brazilian Pharmacopeia is Anemopaegma arvense (Bignoniaceae), but many other plants, regionally known as Catuaba, are commiercialised. Frequently, the quality control of such a complex system is based on chemical markers that do not supply a general idea of the system. With the advent of the metabolomics approach, a global analysis of samples becomes possible. It appears that H-1-NMR is the most useful method for such application, since it can be used as a wide-spectrum chemical analysis technique. Unfortunately, the generated spectra is complex so a possible approach is to look at the metabolite profile as a whole using multivariate methods, for example, by application of principal component analysis (PCA). In the present paper, we describe for the first time a proton high-resolution magic angle spinning nuclear magnetic resonance (H-1-HR-MAS NMR) method coupled with PCA for the metabolomic analysis of some commercial Catuaba samples, which provided a reduction in the time required for such analysis. A comparative study of HPLC, HR-MAS and liquid-NMR techniques is also reported. Copyright (c) 2007 John Wiley & Sons, Ltd.19321822
Involvement of nitric oxide in the gastroprotective effects of an aqueous extract of Pfaffia glomerata (Spreng) Pedersen, Amaranthaceae, in rats
The plants belonging to Pfaffia genus are used in folk medicine to treat gastric disturbances. This study examined the effects of an aqueous extract of Pfaffia glomerata (Spreng) Pedersen (AEP) on the gastrointestinal tract. Wistar rats were pretreated orally (p.o.) with the AEP (125, 250, 500 and 1000 mg.kg(-1)) before induction of ulcers by hypothermic restraint stress (HRS, 3 h restraint stress at 4 degreesC), ethanol (ET, 70%; 0.5 ml/animal; p.o.) or indomethacin (IND, 20 mg.kg(-1); s.c.). Control animals received water (C) or ranitidine (60 mg.kg(-1)) p.o. The AEP protected rats against HRS and ET-induced ulcers, but was not able to protect the gastric mucosa against IND-induced ulcers. When injected into the duodenal lumen, the AEP reduced total acidity and both basal and histamine-stimulated acid secretion in pylorus-ligated rats. In addition, gastric secretion from AEP-treated animals exhibited increased concentrations of nitrite and nitrate. Treatment of animals with L-NAME (120 mg.kg(-1), p.o.) prevented both the reduction of total acidity and the increase in NO, levels promoted by AEP treatment. In conclusion, AEP effectively protected the gastric mucosa and inhibited gastric acid secretion in rats, probably by involving the histaminergic pathway and an enhanced production of nitric oxide in the stomach. (C) 2003 Elsevier B.V. All rights reserved