Caffeine impairs short-term neurological outcome after concussive head injury in rats

Khalaf Al Moutaery, Saleh Al Deeb, Haseeb Ahmad Khan, Mohammad Tariq, Alex B. Valadka, Raj K. Narayan, David Yeh

Research output: Contribution to journalArticlepeer-review

32 Scopus citations


OBJECTIVE: Adenosine is an endogenous neuroprotective agent that is released during ischemia, hypoxia, epilepsy, and ischemic brain injury. Caffeine is a receptor antagonist for adenosine that might interfere with the neuroprotective effect of adenosine in ischemic-hypoxic conditions. An investigation was undertaken to study the effect of caffeine on neurological function, edema formation, and blood-brain barrier permeability after experimental head injury in rats. METHODS: Adult female Wistar rats classified into different groups received caffeine intraperitoneally at doses of 0, 50, 100, and 150 mg/kg body weight. Thirty minutes after the caffeine treatment, the animals were subjected to concussive head injury (CHI) administered by a controlled cortical impact device. Neurological severity score was recorded in each rat at 2 hours after CHI. Specific gravity, water content (as an indicator of edema), and blood-]brain barrier impairment were analyzed in the cortical tissue surrounding the injury site. The levels of myeloperoxidase and malondialdehyde in the cortical region were measured as indicators of neutrophil infiltration and lipid peroxidation, respectively. RESULTS: A significant increase in righting latency and neurological deficiency after CHl was observed in caffeine-treated rats as compared with untreated animals. Although no deaths occurred in the rats exposed to CHI after pretreatment with saline, pretreatment with caffeine caused significant mortality of animals after trauma in a dose-dependent manner. Caffeine also exacerbated neutrophil infiltration, edema, and disruption of blood-brain barrier in the traumatic cortex. Light microscopy of brain revealed more severe hemorrhage and neuronal degeneration in the injured hemisphere of caffeine-treated rats as compared with rats in the injury-alone group. A significant increase in malondialdehyde in the brain of injured rats treated with caffeine before CHI clearly indicated the role of oxidative stress. CONCLUSION: Caffeine adversely affects outcome after CHI, possibly as a result of blockade of adenosine receptors. The findings also point toward the involvement of free radical-mediated neuronal damage in caffeine-induced exacerbation of neurotrauma.

Original languageEnglish (US)
Pages (from-to)704-712
Number of pages9
Issue number3
StatePublished - Sep 1 2003
Externally publishedYes


  • Adenosine
  • Caffeine
  • Free radicals
  • Head injury
  • Neurotrauma
  • Secondary injury

ASJC Scopus subject areas

  • Surgery
  • Clinical Neurology


Dive into the research topics of 'Caffeine impairs short-term neurological outcome after concussive head injury in rats'. Together they form a unique fingerprint.

Cite this