title: Exogenous Testosterone, Aging, and Changes in Behavioral Response of Gonadally Intact Male Mice.
abstract: This study tested the hypothesis that aging significantly affects the influence of exogenous testosterone on neurobehavior in gonadally intact male mice. Groups of prepubertal and aged male mice received daily vehicle or testosterone propionate (TP; 2.5 or 5.0 mg/kg intraperitoneal [i.p.]) for 21 days. Behaviors were assessed on days 1 and 21. Weight gain was significant in prepubertal mice. Locomotion and rearing increased in prepubertal mice after first dose and decreased after last dose of TP. Rearing was suppressed in aged mice throughout. Suppression of grooming occurred in both age groups at day 21. Significant increase in working memory in both age groups was seen in the radial-arm maze (at specific doses) and in prepubertal mice in the Y-maze. Elevated plus maze test showed mixed anxiolytic/anxiogenic effects. Aged mice had higher serum testosterone. In conclusion, age is an important determinant for the influence of exogenous testosterone on behavior in gonadally intact male mice.
authors.affiliation: Department of Pharmacology, Faculty of Basic Medical Sciences, College of Health Sciences, Ladoke Akintola University of Technology, Oshogbo, Osun State, Nigeria.
authors.forename: Olakunle J
authors.initials: OJ
authors.lastname: Onaolapo
authors.affiliation: Department of Human Anatomy, Faculty of Basic Medical Sciences, College of Health Sciences, Ladoke Akintola University of Technology, Ogbomosho, Oyo State, Nigeria.
authors.forename: Adejoke Y
authors.initials: AY
authors.lastname: Onaolapo
authors.affiliation: Department of Human Anatomy, Faculty of Basic Medical Sciences, College of Health Sciences, Ladoke Akintola University of Technology, Ogbomosho, Oyo State, Nigeria.
authors.forename: Tope A
authors.initials: TA
authors.lastname: Omololu
authors.affiliation: Department of Human Anatomy, Faculty of Basic Medical Sciences, College of Health Sciences, Ladoke Akintola University of Technology, Ogbomosho, Oyo State, Nigeria.
authors.forename: Adedunke T
authors.initials: AT
authors.lastname: Oludimu
authors.affiliation: Department of Human Anatomy, Faculty of Basic Medical Sciences, College of Health Sciences, Ladoke Akintola University of Technology, Ogbomosho, Oyo State, Nigeria.
authors.forename: Toluwalase
authors.initials: T
authors.lastname: Segun-Busari
authors.affiliation: Department of Human Anatomy, Faculty of Basic Medical Sciences, College of Health Sciences, Ladoke Akintola University of Technology, Ogbomosho, Oyo State, Nigeria.
authors.forename: Taofeeq
authors.initials: T
authors.lastname: Omoleke
keywords: age; androgens; anxiety; central excitation; cognition; novelty-induced behaviors