The long-term effects of adolescent ¿ 9-tetrahydrocannabinol on brain structure and function assessed through neuroimaging techniques in male and female rats Articles uri icon

authors

  • Orihuel, Javier
  • CAPELLAN, ROBERTO
  • CASQUERO VEIGA, MARTA
  • SOTO MONTENEGRO, Mª LUISA
  • DESCO MENENDEZ, MANUEL
  • OTEO-VIVES, MARTA
  • IBAÑEZ-MORAGUES, MARTA
  • MAGRO-CALVO, NATALIA
  • LUJAN, VICTO M.
  • MORCILLO, MIGUEL ANGEL
  • AMBROSIO, EMILIO
  • HIGUERA-MATAS, ALEJANDRO

publication date

  • September 2023

start page

  • 47

end page

  • 63

issue

  • September

volume

  • 74

International Standard Serial Number (ISSN)

  • 0924-977X

Electronic International Standard Serial Number (EISSN)

  • 1873-7862

abstract

  • Several studies performed on human subjects have examined the effects of adolescent cannabis consumption on brain structure or function using brain imaging techniques. However, the evidence from these studies is usually heterogenous and affected by several confounding variables. Animal models of adolescent cannabinoid exposure may help to overcome these difficulties. In this exploratory study, we aim to increase our understanding of the protracted effects of adolescent ∆9-tetrahydrocannabinol (THC) in rats of both sexes using magnetic resonance (MR) to obtain volumetric data, assess grey and white matter microstructure with diffusion tensor imaging (DTI) and measure brain metabolites with 1H-MR spectroscopy (MRS); in addition, we studied brain function using positron emission tomography (PET) with 2-deoxy-2-[18F]fluoro-d-glucose as the tracer. THC-exposed rats exhibited volumetric and microstructural alterations in the striatum, globus pallidus, lateral ventricles, thalamus, and septal nuclei in a sex-specific manner. THC administration also reduced fractional anisotropy in several white matter tracts, prominently in rostral sections, while in vivo MRS identified lower levels of cortical choline compounds. THC-treated males had increased metabolism in the cerebellum and olfactory bulb and decreased metabolism in the cingulate cortex. By contrast, THC-treated females showed hypermetabolism in a cluster of voxels comprising the entorhinal piriform cortices and in the cingulate cortex. These results indicate that mild THC exposure during adolescence leaves a lingering mark on brain structure and function in a sex-dependant manner. Some of the changes found here resemble those observed in human studies and highlight the importance of studying sex-specific effects in cannabinoid research.

subjects

  • Biology and Biomedicine
  • Industrial Engineering

keywords

  • adolescence; mri; pet; spectroscopy; thc