title: Promnestic effects of intranasally applied pregnenolone in rats.
abstract: The neurosteroid pregnenolone (PREG) has been shown to have memory-enhancing and anti-depressant action. The present study addresses the question of whether intranasally applied pregnenolone (IN-PREG) also has promnestic properties in the rat. We examined the effects of IN-PREG at doses of 0.187 and 0.373mg/kg on memory for objects and their location on learning and retention of escape in a water maze, and on behavior on the elevated plus maze. The main findings were: (a) Pre-trial, but not post-trial, administration of IN-PREG facilitated long-term memory in a novel object-preference test and a novel object-location preference test when tested 48h after dosing. (b) Over the duration of 5days of extinction trials, after learning to escape onto a hidden platform in a water maze, the animals treated with IN-PREG spent more time in searching for the absent platform, indicating either, or both, superior memory for the former position of the escape platform, or a higher resistance to extinction. (c) Administration of the anticholinergic, scopolamine, disrupted learning to escape from the water maze in the vehicle-treated group. The IN-PREG treated groups exhibited superior escape learning in comparison with vehicle controls, indicating that the treatment countered the scopolamine effect. IN-PREG treatment had no influence on behaviors on the elevated plus maze. Our results demonstrate that IN-PREG is behaviorally active with cognitive enhancing properties comparable to those known from studies employing systemic PREG administration.
authors.affiliation: Center for Behavioral Neuroscience, Institute of Experimental Psychology, University of Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany. Electronic address: lailasabersaleh@yahoo.com.
authors.forename: Laila
authors.initials: L
authors.lastname: Abdel-Hafiz
authors.affiliation: Center for Behavioral Neuroscience, Institute of Experimental Psychology, University of Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany. Electronic address: owenchao@gmail.com.
authors.forename: Owen Y
authors.initials: OY
authors.lastname: Chao
authors.affiliation: Center for Behavioral Neuroscience, Institute of Experimental Psychology, University of Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany. Electronic address: jph@uni-duesseldorf.de.
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Huston
authors.affiliation: Clinic of Nuclear Medicine, University Hospital Düsseldorf, 40225 Düsseldorf, Germany. Electronic address: Susanne.Nikolaus@uni-duesseldorf.com.
authors.forename: Susanne
authors.initials: S
authors.lastname: Nikolaus
authors.affiliation: Oceanographic Center, Nova Southeastern University, Fort Lauderdale, FL 33314, USA. Electronic address: spielerr@nova.edu.
authors.forename: Richard E
authors.initials: RE
authors.lastname: Spieler
authors.affiliation: Center for Behavioral Neuroscience, Institute of Experimental Psychology, University of Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany. Electronic address: desouza@uni-duesseldorf.de.
authors.forename: Maria A
authors.initials: MA
authors.lastname: de Souza Silva
authors.affiliation: Oceanographic Center, Nova Southeastern University, Fort Lauderdale, FL 33314, USA; M et P Pharma AG, 6376 Emmetten, Switzerland. Electronic address: info@mattern-pharma.com.
authors.forename: Claudia
authors.initials: C
authors.lastname: Mattern
mesh_terms: D000818:Animals; D018680:Cholinergic Antagonists / Q000008:administration & dosage / Q000494:pharmacology; D060825:Cognitive Dysfunction / Q000139:chemically induced / Q000517:prevention & control*; D008297:Male; D018782:Maze Learning / Q000187:drug effects*; D057567:Memory, Long-Term / Q000187:drug effects*; D018697:Nootropic Agents / Q000008:administration & dosage / Q000494:pharmacology*; D011284:Pregnenolone / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D021641:Recognition, Psychology / Q000187:drug effects*; D012601:Scopolamine / Q000008:administration & dosage / Q000494:pharmacology; D065852:Spatial Memory / Q000187:drug effects*
chemical_list: D018680:Cholinergic Antagonists; D018697:Nootropic Agents; D011284:Pregnenolone; D012601:Scopolamine
keywords: Intranasal drug administration; Memory; Neurosteroid; Object recognition; Pregnenolone; Water maze