Effects of testosterone on hippocampal CA1 spine synaptic density in the male rat are inhibited by fimbria/fornix transection.
This study investigated the contribution of sub-cortical afferent input to the effects of testosterone (T) on spine synapse density in the CA1 subfield of the hippocampus, in adult male rats. Gonadectomized (GDX) male rats exhibited a considerably lower density of spine synapses in the CA1 region than control, intact males. The effects of GDX were reversed by treatment with testosterone propionate (TP; 500 microg/day, for 2 days). Transection of the fimbria/fornix (FF) had no significant effect on the synaptic density in non-GDX males. However, FF transection partially inhibited the responses to TP in GDX animals. These data suggest that the effects of T on spine synapse density in the CA1 region of the male rat hippocampus are partially, but not completely, dependent on afferent sub-cortical input.
Kovacs
E G
EG
Department of Obstetrics and Gynecology, Yale University School of Medicine, 333 Cedar Street, FMB 328, New Haven, CT 06520, USA.
MacLusky
N J
NJ
Leranth
C
C
D000704:Analysis of Variance; D000818:Animals; D002452:Cell Count; D003714:Denervation / Q000379:methods; D020712:Fornix, Brain / Q000473:pathology / Q000601:surgery*; D012739:Gonadal Steroid Hormones / Q000494:pharmacology; D006624:Hippocampus / Q000166:cytology*; D008297:Male; D008854:Microscopy, Electron / Q000379:methods; D009919:Orchiectomy / Q000379:methods; D017966:Pyramidal Cells / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013569:Synapses / Q000187:drug effects* / Q000648:ultrastructure; D013739:Testosterone / Q000494:pharmacology*
D012739:Gonadal Steroid Hormones; D013739:Testosterone