Effect of intrauterine position on sex differences in the gabaergic system and behavior of rats

Hernández-Tristán, R.; Leret, M.L.; Almeida, Dennys Ramon de Melo Fernandes

doi:10.1016/j.physbeh.2006.01.002

Cited by 8 publications

(2 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the present study, AGD was dependent on the total number of males within the uterine horn, consistent with previous literature demonstrating that androgen exposure, resulting from the proximity to male littermates, has significant influence over the neural and behavioural development of female mice and rats (20, 21, 30, 33, 43, 44). The fetal testes differentiate during the second week of gestation and begin to secrete testosterone by ED14.5–15.5 (45).…”

Section: Discussionsupporting

confidence: 92%

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

Jahagirdar

Quadros

Wagner

2008

J Neuroendocrinology

View full text Add to dashboard Cite

Testosterone secreted by male testes during fetal development is aromatized to oestradiol (E(2)) or reduced to the androgen, dihydrotestosteorne (DHT), within specific tissues. The female brain is assumed to develop in the relative absence of gonadal steroid hormones, as the ovary is steroidogenically quiescent until later in postnatal life. However, the proximity of a female fetus to male littermates in utero can increase her exposure to testosterone, and thereby its metabolites. To date, it is has been difficult to dissociate the effects of male-derived E(2) from those of DHT on the developing female brain. In the present study, anogential distance (AGD) in females was used as an androgen-dependent bioassay, whereas progesterone receptor (PR) expression within the medial preoptic nucleus (MPN) was used as an E-dependent measure. Pregnant dams received the aromatase inhibitor, 1,4,6-androstatriene-3,17-dione (ATD), or vehicle from embryonic day 16 (ED16) to ED21. On ED22, AGD and PR-immunoreactivity (-ir) were measured in females that had zero, one, or two males (0-2M) or females that had three, four, or five males (3-5M) in the uterine horn. AGD was significantly greater in 3-5M females compared to 0-2M females, suggesting that male littermates are the source of androgenic exposure in the female fetus. ATD treatment significantly decreased PR-ir in the MPN, demonstrating E(2) regulation of PR. However, the total number of males in the uterine horn did not effect PR expression. There was no correlation between PR-ir and AGD, suggesting that these measures are influenced independently. Together, these results suggest that although male littermates provide a significant source of androgens to female fetuses, the amount of E(2) aromatized from male-derived testosterone may not be the only biologically relevant source of androgens or E(2). Alternative sources of E(2) may be essential in ensuring the normal development of the female brain.

show abstract

Section: Discussionsupporting

confidence: 92%

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

Jahagirdar

Quadros

Wagner

2008

J Neuroendocrinology

View full text Add to dashboard Cite

show abstract

“…The intrauterine environment of the fetal rat has been shown, through hormonal (Hernández‐Tristán et al, 2006) and uterine blood and nutrient supply (McLaren and Michie, 1960; Wentzel et al, 1995) to have an effect on growth pattern and fetal survival (Chahoud and Paumgartten, 2009). Such factors, and likely currently unknown differences in the intrauterine environment in rats, could cause significant variation in fetal body or brain weight as a function of uterine position of the fetus.…”

Section: Introductionmentioning

confidence: 99%

Polytocus focus: Uterine position effect is dependent upon horn size

McLaurin

Mactutus

2014

Intl J of Devlp Neuroscience

View full text Add to dashboard Cite

Understanding the variability caused by uterine position effects in polytocus species, such as rats, may enhance prenatal animal models for the study of drug and environmental agents. The primiparous litters of 42 intact female Sprague-Dawley rats were studied. Uterine position, fetal body weight, and fetal brain (wet) weight were recorded on gestation day (GD) 20 (GD 0 = sperm positive). Uterine position effect for brain and body weight varied depending upon horn size. Furthermore, an inverse relationship between horn size (and, to a lesser extent, litter size) and fetal weight applied to both body and brain weight measures. There were no statistical differences in brain and body weights between the left and right uterine horns. The position of the uterine horn (left vs. right) and litter size did not influence the uterine position effect in the rat. Collectively, the present data suggest the presence of a significant uterine position effect. Prenatal differences based on uterine position provide an untapped opportunity to increase our understanding of developmental neurotoxicological and teratological studies that employ a polytocus species as an animal model.

show abstract

The Hole-Board Test in Mutant Mice

Lalonde

Strazielle

2022

Behav Genet

View full text Add to dashboard Cite

Effect of intrauterine position on sex differences in the gabaergic system and behavior of rats

Cited by 8 publications

References 72 publications

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

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

Polytocus focus: Uterine position effect is dependent upon horn size

The Hole-Board Test in Mutant Mice

Contact Info

Product

Resources

About