6533b82ffe1ef96bd1294699

RESEARCH PRODUCT

Nigral influence on focal epilepsy.

M. SabatinoGiuseppe FerraroN. VellaV. La Grutta

subject

Decerebrate StateChemistryPars compactaHippocampusStimulationSubstantia nigraGeneral MedicinePenicillinsHippocampal formationInhibitory postsynaptic potentialHippocampusElectric StimulationSubstantia NigraNeurologyPhysiology (medical)CatsAnimalsIctalNeurology (clinical)Epilepsies PartialPars reticulataNeuroscience

description

The substantia nigra (SN) has been proposed as a structure involved in epileptiform phenomena. Previous investigations demonstrated that SN is able to elicit hippocampal rhythmic slow activity (RSA) as well as to inhibit hippocampal interictal spikes induced by parenteral administration of penicillin. The present series of experiments was carried out in order to characterize the action of SN on a focal model of hippocampal epilepsy. Experiments were performed on encephale isole cats in which steady epileptiform activity was induced by locally applied penicillin. Electrical stimulation of SN pars reticulata (pr) caused a statistically significant decrease of hippocampal spike frequency and amplitude in 30% of the total number of stimulation sessions. Stimulation of SN pars compacta (pc) was even more effective. It induced inhibitory effects on hippocampal spikes in 91% of the cases. In 30% of the cats, RSA was noted on hippocampal recordings in correspondence to nigral activation. Experimental data support the hypothesis that the SNpc influences hippocampal excitability: a differential role may be played by SNpc and SNpr in the control of seizure processes.

10.1016/s0987-7053(05)80154-6https://pubmed.ncbi.nlm.nih.gov/2122206