Hippocampal 5-hydroxytryptamine synthesis is greater in female rats than in males and more decreased by the 5-HT1A agonist 8-OH-DPAT.
Brain regional 5-hydroxytryptamine (5-HT) and/or 5-hydroxyindoleacetic acid (5-HIAA) concentrations tended to be slightly higher in female rats than in males but differences were substantial only in the hippocampus where female values were 34% and 36% higher respectively. These findings were consistent with the synthesis rates of 5-HT as this was 53% greater in the female than in the male hippocampi. Other regions did not show significant sex differences. The 5-HT1A agonist 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT, 1 mg/kg sc) caused comparable decreases of 5-HT synthesis rate in both sexes and in all regions studied except the hippocampus where the percentage decrease was twice as large in the females (-64%) as in the males (-32%) so that the sex difference in 5-HT synthesis in this region largely disappeared. The results are discussed in relation to sex differences in behaviour and hippocampal function.
Department of Neurochemistry, Institute of Neurology, London, United Kingdom.
D J
DJ
Haleem
G A
GA
Kennett
G
G
Curzon
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D005260:Female; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism*; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D008297:Male; D009281:Naphthalenes / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000096:biosynthesis*; D012727:Sex Characteristics; D013764:Tetrahydronaphthalenes / Q000494:pharmacology*
D009281:Naphthalenes; D013764:Tetrahydronaphthalenes; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin