Inhibition of endoplasmic reticulum stress attenuates morphine protracted abstinence-induced anxiety-like behaviors in the male mice

Brain Res. 2024 Jul 15:1835:148930. doi: 10.1016/j.brainres.2024.148930. Epub 2024 Apr 9.

Abstract

The anxiety caused by morphine protracted abstinence is considered to be an important factor contributes to drug-seeking and relapse. Endoplasmic reticulum (ER) stress plays important roles in many kinds of mental disorders including drug addiction and anxiety, but it is unclear whether ER stress is involved in anxiety-like behaviors induced by morphine withdrawal. In this study, by using behavioral test, western blot, immunofluorescence, electron transmission microscope, we found that: (1) Inhibition of endoplasmic reticulum stress by 4-Phenylbutyric acid (4-PBA) could attenuate anxiety-like behaviors induced by morphine withdrawal. (2) The endoplasmic reticulum stress-related proteins in the lateral habenula (LHb) but not in the nucleus accumbens (NAc), ventral pallidum (VP), basolateral amygdala (BLA) and CA1 of hippocampus was upregulated by morphine withdrawal, upregulation of endoplasmic reticulum stress-related proteins in the lateral habenula induced by morphine withdrawal was inhibited by 4-PBA. (3) Endoplasmic reticulum stress-related protein CHOP and eIF2α were expressed in neurons but not in microglia in the LHb. (4) Morphine withdrawal induced neuronal morphological change in the LHb, which was attenuated by 4-PBA.

Keywords: Anxiety; Endoplasmic reticulum stress; LHb; Morphine withdrawal.

MeSH terms

  • Animals
  • Anxiety* / drug therapy
  • Anxiety* / metabolism
  • Endoplasmic Reticulum Stress* / drug effects
  • Endoplasmic Reticulum Stress* / physiology
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Morphine Dependence / metabolism
  • Morphine* / pharmacology
  • Neurons / drug effects
  • Neurons / metabolism
  • Phenylbutyrates / pharmacology
  • Substance Withdrawal Syndrome* / metabolism

Substances

  • 4-phenylbutyric acid