Neonatal inhibition of brain estrogen formation in male rats by administration of the aromatase inhibitor, 1,4,6-androstatriene-3,17-dione (ATD), permanently changes aspects of their mating behavior and partner preference in adulthood. The medial preoptic area receives chemosensory inputs via a sexually dimorphic vomeronasal projection circuit, which responds to reproductively relevant pheromon...

–Using quantitative immunocytochemical procedures, the total number of estrogen and androgen receptors was estimated in a large number of hypothalamic and limbic nuclei of male rats, in which brain estrogen formation was inhibited neonatally by treatment with the aromatase inhibitor 1,4,6androstatriene-3,17-dione. The highest densities of estrogen receptor immunoreactivity were observed in the ...

The synaptic interactions between catecholaminergic terminals and luteinizing hormone releasing hormone (LHRH)-containing neurons in the medial preoptic area of the rat was studied by electron microscopy using LHRH immunocytochemistry combined with 5-hydroxydopamine labeling or autoradiography after injection of 3H-dopamine or 3H-noradrenaline in the same tissue section. Axon terminals labeled ...

We investigated the participation of neuropeptide Y-Y1 receptors within the medial preoptic area in luteinizing hormone, follicle-stimulating hormone and prolactin release. Four bilateral microinjections of sense (control) or antisense 18-base oligonucleotides of messenger ribonucleic acid (mRNA) (250 ng) corresponding to the NH2-terminus of the neuropeptide Y1 receptor were performed at 12-h i...

Male rat copulation is mediated by estrogen-sensitive neurons in the medial preoptic area (MPO) and medial amygdala (MEA); however, the mechanisms through which estradiol (E2) acts are not fully understood. We hypothesized that E2 acts through estrogen receptor α (ERα) in the MPO and MEA to promote male mating behavior. Antisense oligodeoxynucleotides (ASODN) complementary to ERα mRNA were bila...

In female rats, the onset of reproductive behavior depends on the sequential presence of estradiol followed by progesterone. Although treatment with high doses of estradiol has been shown to increase immunostaining for the Fos protein, an immediate early gene product that is expressed upon cellular activation, another report conflicts with this finding. However, the previous reports agree that ...

To determine if substance P- or prodynorphin-containing neurons of the medial nucleus of the amygdala and medial bed nucleus of the stria terminalis send projections to the medial preoptic area in the male Syrian hamster, we placed a fluorescent retrograde tract tracer (either Fluoro-gold, or rhodamine- or fluorescein-impregnated latex microspheres) into the medial preoptic area. Five to seven ...