, Volume 44, Issue 6, pp 441–447 | Cite as

Attenuation of Formalin-Induced Inflammatory Nociception by Propentofylline: Modulation of Glia

  • M.-L. Sun
  • H.-X. Yu
  • J. Tian
  • Y.-Q. Yu

We examined the effects of propentofylline (PPF) injected intracerebroventricularly (i.c.v., 30 mM, 10 μl) into female Sprague–Dawley rats on pain responses in the formalin test and on the number of glial fibrillary acidic protein-immunopositive (GFAP-ip) astrocytes in the caudatoputamen (CPu) and periaqueductal grey (PAG) of these animals. The mean durations of flinch and lifting/biting of the limb in the PPF group vs. the vehicle (normal saline) group within phase 1 of the pain response were 280.0 ± ± 71.6 vs. 401.0 ± 69.0 sec and 69.5 ± 34.8 vs. 145.5 ± 18.6 sec, respectively (P > 0.05 in both cases, n = 7). During phase 2, the respective figures were 152.6 ± 104.0 vs. 1602.7 ± 100.9 sec and 79.1 ± ± 69.1 vs. 376.1 ± 56.5 sec (P < 0.01 in both cases). The mean numbers of GFAP-positive astrocytes per slice observed in the PPF and vehicle groups in the CPu were 35 ± 3.1 vs. 55 ± 1.9 (P < 0.01, n = 7), and those in the PAG were 30 ± 2.2 vs. 49 ± 1.2 (P < 0.01, n = 11). Thus, i. c.v. administration of PPF suppresses inflammatory pain induced by formalin injection in rats; there are reasons to believe that glial cells (astrocytes) in certain brain structures are intensely involved in the formation of a sensation of inflammatory pain.


astrocytes formalin test pain propentofylline caudatoputamen periaqueductal grey 


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Copyright information

© Springer Science+Business Media New York 2012

Authors and Affiliations

  1. 1.Key Laboratory of Medical Neurobiology of Ministry of Health, Zhejiang Province Key Laboratory of NeurobiologyZhejiang University School of MedicineHangzhouChina
  2. 2.Luohe Medical CollegeLuoheChina

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