Studies of the Effects of Monoamines on Orexinergic Neurons in the Hypothalamus of Rat Embryos

Hypothalamic orexinergic neurons are involved in controlling various body functions, particularly energy balance, feeding behavior, wakefulness, and awakening. The direct effects of brain dopamine and serotonin on orexinergic neurons in the hypothalamus are mediated via various subtypes of the corresponding receptors, whose expression has previously been demonstrated in the bodies of orexinergic neurons. Studies were performed on 18-day rat embryos to assess the possibility that these interactions form during the embryonic period of development. Western blotting was used to demonstrate expression of dopamine D1 and serotonin 2C receptor proteins in the developing hypothalamus. Studies using double fluorescence immunolabeling and confocal microscopy confirmed the expression of dopamine D1 and serotonin 2C receptors in the bodies of developing orexin-immunopositive cells in rat embryos. These results provide evidence that the development of morphofunctional interactions between the monoaminergic systems and the orexinergic system occur during the embryonic period of development.

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Correspondence to I. V. Romanova.

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Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 106, No. 6, pp. 728–739, June, 2020.

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Morina, I.Y., Mikhailova, E.V. & Romanova, I.V. Studies of the Effects of Monoamines on Orexinergic Neurons in the Hypothalamus of Rat Embryos. Neurosci Behav Physi 51, 350–356 (2021).

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  • orexins
  • hypothalamus
  • dopamine
  • serotonin
  • dopamine D1 receptors
  • serotonin 2C receptors
  • orexin receptors
  • embryogenesis
  • E18