Modulation of B1 and B2 kinin receptors expression levels in the hippocampus of rats after audiogenic kindling and with limbic recruitment, a model of temporal lobe epilepsy.
Epileptic seizures are hypersynchronous, paroxystic and abnormal neuronal discharges. Epilepsies are characterized by diverse mechanisms involving alteration of excitatory and inhibitory neurotransmission that result in hyperexcitability of the central nervous system (CNS). Enhanced neuronal excitability can also be achieved by inflammatory processes, including the participation of cytokines, prostaglandins or kinins, molecules known to be involved in either triggering or in the establishment of inflammation. Multiple inductions of audiogenic seizures in the Wistar audiogenic rat (WAR) strain are a model of temporal lobe epilepsy (TLE), due to the recruitment of limbic areas such as hippocampus and amygdala. In this study we investigated the modulation of the B1 and B2 kinin receptors expression levels in neonatal WARs as well as in adult WARs subjected to the TLE model. The expression levels of pro-inflammatory (IL-1 beta) and anti-inflammatory (IL-10) cytokines were also evaluated, as well as cyclooxygenase (COX-2). Our results showed that the B1 and B2 kinin receptors mRNAs were up-regulated about 7- and 4-fold, respectively, in the hippocampus of kindled WARs. On the other hand, the expressions of the IL-1 beta, IL-10 and COX-2 were not related to the observed increase of expression of kinin receptors. Based on those results we believe that the B1 and B2 kinin receptors have a pivotal role in this model of TLE, although their participation is not related to an inflammatory process. We believe that kinin receptors in the CNS may act in seizure mechanisms by participating in a specific kininergic neurochemical pathway.
Pereira
Marilia G A G
MG
Department of Biochemistry and Immunology, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
Gitaí
Daniel L G
DL
Paçó-Larson
Maria L
ML
Pesquero
João B
JB
Garcia-Cairasco
Norberto
N
Costa-Neto
Claudio M
CM
D000161:Acoustic Stimulation; D000818:Animals; D051546:Cyclooxygenase 2 / Q000235:genetics; D004195:Disease Models, Animal; D004833:Epilepsy, Temporal Lobe / Q000378:metabolism*; D005260:Female; D006624:Hippocampus / Q000378:metabolism*; D016753:Interleukin-10 / Q000235:genetics; D053583:Interleukin-1beta / Q000235:genetics; D007696:Kindling, Neurologic; D008032:Limbic System / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D043783:Receptor, Bradykinin B1 / Q000235:genetics*; D043782:Receptor, Bradykinin B2 / Q000235:genetics*
D053583:Interleukin-1beta; D012333:RNA, Messenger; D043783:Receptor, Bradykinin B1; D043782:Receptor, Bradykinin B2; D016753:Interleukin-10; D051546:Cyclooxygenase 2; C489691:Ptgs2 protein, rat