Dataset Information

Gonadal hormone-independent sex differences in GABA_A receptor activation in rat embryonic hypothalamic neurons.

ABSTRACT:

Background and purpose

GABA_A receptor functions are dependent on subunit composition, and, through their activation, GABA can exert trophic actions in immature neurons. Although several sex differences in GABA-mediated responses are known to be dependent on gonadal hormones, few studies have dealt with sex differences detected before the critical period of brain masculinisation. In this study, we assessed GABA_A receptor functionality in sexually segregated neurons before brain hormonal masculinisation.

Experimental approach

Ventromedial hypothalamic neurons were obtained from embryonic day 16 rat brains and grown in vitro for 2 days. Calcium imaging and electrophysiology recordings were carried out to assess GABA_A receptor functional parameters.

Key results

GABA_A receptor activation elicited calcium entry in immature hypothalamic neurons mainly through L-type voltage-dependent calcium channels. Nifedipine blocked calcium entry more efficiently in male than in female neurons. There were more male than female neurons responding to GABA, and they needed more time to return to resting levels. Pharmacological characterisation revealed that propofol enhanced GABA_A -mediated currents and blunted GABA-mediated calcium entry more efficiently in female neurons than in males. Testosterone treatment did not erase such sex differences. These data suggest sex differences in the expression of GABA_A receptor subtypes.

Conclusion and implications

GABA-mediated responses are sexually dimorphic even in the absence of gonadal hormone influence, suggesting genetically biased differences. These results highlight the importance of GABA_A receptors in hypothalamic neurons even before hormonal masculinisation of the brain.

SUBMITTER: Mir FR

PROVIDER: S-EPMC7280008 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Dataset Information

Gonadal hormone-independent sex differences in GABA_A receptor activation in rat embryonic hypothalamic neurons.

Background and purpose

Experimental approach

Key results

Conclusion and implications

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

Gonadal hormone-independent sex differences in GABAA receptor activation in rat embryonic hypothalamic neurons.

Background and purpose

Experimental approach

Key results

Conclusion and implications

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Gonadal hormone-independent sex differences in GABA_A receptor activation in rat embryonic hypothalamic neurons.