Identification of neural circuits controlling male sexual behavior and sexual motivation by manganese-enhanced magnetic resonance imaging.

Introduction: Different techniques have been used to identify the brain regions that control sexual motivation and sexual behavior. However, the influence of sexual experience on the activation of these brain regions in the same subject is unknown. Using manganese-enhanced magnetic resonance imaging (MEMRI), we analyzed the activation of brain regions in the sexual incentive motivation (SIM) and the partner preference PP (tests) on weeks 1, 5, and 10 in male rats tested for 10 weeks.

haploinsufficiency causes brain abnormalities with functional relevance.

Introduction: The Notch pathway is fundamental for the generation of neurons during development. We previously reported that adult mice heterozygous for the null allele of the gene encoding the Delta-like ligand 1 for Notch ( ) have a reduced neuronal density in the substantia nigra pars compacta. The aim of the present work was to evaluate whether this alteration extends to other brain structures and the behavioral consequences of affected subjects.

Role of Oestrogen α Receptors in Sociosexual Behaviour in Female Rats Housed in a Seminatural Environment.

The present study investigated the role of oestrogen receptor (ER)α in the ventromedial nucleus of the hypothalamus (VMN), the preoptic area (POA), the medial amygdala (MePD) and the bed nucleus of stria terminalis (BNST) in sociosexual behaviour in female rats. This was conducted in two sets of experiments, with the VMN and POA investigated in the first set, and the MePD and BNST in the second set. The VMN and POA received intense projections from the MePD and BNST.

Testosterone or oestradiol implants in the medial preoptic area induce mating in noncopulating male rats.

Noncopulating (NC) male rats are those males that do not mount, intromit or ejaculate when repeatedly tested with receptive females. The lack of sexual behaviour in these males is not associated with alterations in testosterone or oestradiol (E2) plasma concentrations. Instead, it has been shown that androgen receptors are higher and oestrogen receptors are lower in the medial preoptic area (MPOA) of NC male rats than those observed in copulating (C) male rats.

Behavioral characterization of non-copulating male mice.

Non-copulating (NC) males are those animals that do not mate in spite of repeated testing with sexually receptive females. They have been observed in several species including rats and mice. The present experiment was designed to perform a detailed behavioral characterization of NC male mice.