MK801- and scopolamine-induced amnesias are reversed by an Amazonian herbal locally used as a "brain tonic".
BACKGROUND
Traditional remedies prepared from Ptychopetalum olacoides (PO) are used throughout the Amazon to alleviate age-related conditions. These formulas are mainly used by elders, and alleged effects may be related to the anticholinesterase properties identified in a standardized ethanol extract of this species [P. olacoides standardized ethanol extract (POEE)].


OBJECTIVE
To further characterize the potential of this extract for developing drugs useful to treat cognitive deficits, the effects of POEE on scopolamine (scop)- and MK801-induced amnesias (acquisition, consolidation, and retrieval) in mice were investigated.


RESULTS
Scop (3.0 mg/kg, ip) significantly impaired memory (all three phases) in the step-down inhibitory avoidance protocol. As expected, MK801 (0.1 mg/kg, ip) was amnesic regarding acquisition and consolidation, but not retrieval. POEE (100 mg/kg, ip) reversed the scop-induced impairment in all three phases of long-term and short memories, whereas only the memory consolidation deficit was reversed with MK801-induced amnesia.


CONCLUSIONS
This study complements previously reported promnesic properties of this plant extract and suggests that POEE may be further developed for treating conditions associated with cognitive deficits, especially those linked with cholinergic malfunction.
da Silva
Adriana Lourenço
AL
Laboratório de Etnofarmacologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Av. Sarmento Leite 500/202, Porto Alegre, RS 90046-900, Brazil.
Silva Martins
Bárbara da
Bd
Linck
Viviane de Moura
Vde M
Herrmann
Ana Paula
AP
Mai
Nathalia
N
Nunes
Domingos S
DS
Elisabetsky
Elaine
E
D000647:Amnesia / Q000139:chemically induced* / Q000188:drug therapy* / Q000523:psychology; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D001938:Brazil; D016291:Dizocilpine Maleate; D004597:Electroshock; D018691:Excitatory Amino Acid Antagonists; D007274:Injections, Intraperitoneal; D008297:Male; D008568:Memory / Q000187:drug effects; D008570:Memory, Short-Term; D051379:Mice; D018727:Muscarinic Antagonists; D031656:Olacaceae / Q000737:chemistry*; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology; D018517:Plant Roots / Q000737:chemistry; D012601:Scopolamine
D018691:Excitatory Amino Acid Antagonists; D018727:Muscarinic Antagonists; D010936:Plant Extracts; D016291:Dizocilpine Maleate; D012601:Scopolamine