Right occipital cortex suppresses male rat testosterone secretion by a pituitary-independent mechanism.
OBJECTIVE
In addition to being regulated by the hypothalamo-hypophyseal system, testosterone (T) secretion is influenced by a number of less understood mechanisms. The aim of the present study was to examine whether defined areas of the right cerebral cortex could modulate T production.


METHODS
In adult male Wistar rats right frontal or occipital decortication, anterior or posterior callosotomy and corresponding sham-operations were performed. After 7-day survival time, T secretion in vitro, serum T and LH concentrations were measured by RIA.


RESULTS
Right occipital decortication and posterior callosotomy resulted in an increase in T secretion in vitro when compared to the corresponding sham-operated controls. In contrast, right frontal decortication or anterior callosotomy did not interfere with steroidogenesis. Serum LH concentration was not altered by any interventions.


CONCLUSIONS
The right occipital but not the right frontal cortex is involved in the control of T secretion. The caudal part of the corpus callosum accommodating the fibers originating from the occipital cortex might have a similar function. The fact that LH remained unchanged in all experimental groups suggests that the right occipital cortex and the caudal part of the corpus callosum influence testicular steroidogenesis by a pituitary-independent mechanism.
Lepore
Gianluca
G
Department of Animal Biology, University of Sassari, Italy.
Zedda
Marco
M
Gerendai
Ida
I
Csernus
Valér
V
Gadau
Sergio
S
Manca
Paolo
P
Chisu
Valentina
V
Farina
Vittorio
V
D000818:Animals; D002541:Cerebral Decortication; D003337:Corpus Callosum / Q000166:cytology / Q000502:physiology; D003714:Denervation; D005625:Frontal Lobe / Q000166:cytology / Q000502:physiology; D007839:Functional Laterality; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D009434:Neural Pathways; D009778:Occipital Lobe / Q000166:cytology / Q000502:physiology*; D010903:Pituitary Gland, Anterior / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013739:Testosterone / Q000097:blood* / Q000378:metabolism
D013739:Testosterone; D007986:Luteinizing Hormone