Intrauterine proximity to male fetuses affects the morphology of the sexually dimorphic nucleus of the preoptic area in the adult rat brain

  title={Intrauterine proximity to male fetuses affects the morphology of the sexually dimorphic nucleus of the preoptic area in the adult rat brain},
  author={Minjuan Pei and Ken-Ichi Matsuda and Hirotaka Sakamoto and Mitsuhiro Kawata},
  journal={European Journal of Neuroscience},
Previous studies on polytocous rodents have revealed that the fetal intrauterine position influences its later anatomy, physiology, reproductive performance and behavior. To investigate whether the position of a fetus in the uterus modifies the development of the brain, we examined whether the structure of the sexually dimorphic nucleus of the preoptic area (SDN‐POA) of rat brains accorded to their intrauterine positions. Brain sections of adult rats gestated between two male fetuses (2M) and… 

Sex differences in brain developing in the presence or absence of gonads

Differences in the area and distribution of immunoreactive calbindin and neuronal nitric oxide synthase in the preoptic area and ventromedial nucleus of the hypothalamus were maintained in male and female SF‐1 KO mice, suggesting gonad‐independent genetic influences on sexually dimorphic brain development.

Gonadal Steroids Regulate Neural Plasticity in the Sexually Dimorphic Nucleus of the Preoptic Area of Adult Male and Female Rats

Results indicate considerable plasticity of the adult rat SDNPOA, and that circulating androgens are required to maintain soma size, but not regional volume in males, and ovarian steroids maintain both soma Size and regional volume of the SDN POA in females.

Intrauterine position affects estrogen receptor α expression in the ventromedial nucleus of the hypothalamus via promoter DNA methylation.

It is found that the IUP affects estrogen receptor (ER)α expression in adult female rats in the ventrolateral region of the hypothalamic ventromedial nucleus (vlVMH), which is associated with sexual behavior.

Does having a twin brother make for a bigger brain?

It is indicated that sharing the uterus with a DZ twin brother increases total brain volume in 9-year olds, and the effect may be transient and limited to a critical period in childhood.

The control of sexual differentiation of the reproductive system and brain.

This review summarizes current knowledge of the genetic and hormonal control of sexual differentiation of the reproductive system, brain and brain function and the effects of endocrine disruptors on sexual differentiation is presented.

Endogenous Oestradiol Regulates Progesterone Receptor Expression in the Brain of Female Rat Fetuses: What is the Source of Oestradiol?

The results suggest that although male littermates provide a significant source of androgens to female fetuses, the amount of E2 aromatised from male‐derived testosterone may not be the only biologically relevant source ofandrogens or E2.

Subtle sex differences in vasopressin mRNA expression in the embryonic mouse brain

These data are significant as they provide the first whole‐brain characterization of the vasopressin system in the embryonic mouse, and are consistent with data from other species, that have documented a sex difference in the vasobinding system during early brain formation.

A recently identified hypothalamic nucleus expressing estrogen receptor α

This unique hypothalamic nucleus with its morphological sex differences and hormonal responsiveness is embedded in a region important for the regulation of endocrine functions and sexual behaviors.



Onset of the hormone-sensitive perinatal period for sexual differentiation of the sexually dimorphic nucleus of the preoptic area in female rats.

It is concluded that with the specific paradigm used in this study SDN-POA development is insensitive prior to day 18 of gestation, the day on which the onset of the hormone-sensitive period occurs.

Further evidence for masculinization of female rats by males located caudally in utero

  • G. RichmondBenjamin D. Sachs
  • Biology
    Hormones and Behavior
  • 1984

Sexually dimorphic regions in the medial preoptic area and the bed nucleus of the stria terminalis of the guinea pig brain: a description and an investigation of their relationship to gonadal steroids in adulthood

Attention to the sex differences in these areas may help elucidate more precisely the neural basis for sexually dimorphic functions, as well as the basic mechanisms underlying sexual differentiation of behavior and the brain.

Influence of maternal grooming, sex and age on Fos immunoreactivity in the preoptic area of neonatal rats: implications for sexual differentiation.

It is suggested that anogenital grooming during early postnatal development induces a rapid activation of cells in the ventral mPOA, but not in the SDN-POA of rats, and there is a greater incidence of cell death in and around theSDN- POA of females vs. males during neonatal development.