Electrical kindling of the hippocampus is associated with functional activation of neuropeptide Y-containing neurons

M. Rizzi, A. Monno, R. Samanin, G. Sperk, A. Vezzani

Research output: Contribution to journalArticle

Abstract

The release of neuropeptide Y (NPY) was measured from hippocampal slices of rats at stage 2 (preconvulsive stage) and stage 5 (full seizure expression) of electrical kindling of the dorsal hippocampus (upper blade of the dentate gyrus). Spontaneous release in naive rats (9.0±0.8 fmol/ml every 10 min) was independent of external Ca2+ but was reduced by 38±3.6% (P <0.05) during 20 min incubation with 5 μM tetrodotoxin. Spontaneous efflux in naive rats did not differ from that in shams (implanted with electrodes but not stimulated) or in rats kindled to stage 2 and stage 5. Twenty-five, 50 and 100 mM KCl induced a concentration-dependent release of NPY (P <0.05 and P <0.01 at 25 and 50-100 mM respectively) from slices of shams. The effect of 100 mM KCl was reduced by 94±1% (P <0.01) in the absence of Ca2+. Two days after the last stage 2 stimulation and 1 week after the last stage 5 seizure, NPY release was significantly larger than in shams at all KCl concentrations in the stimulated and contralateral hippocampus (P <0.05 and P <0.01). Forty-eight hours after one single after-discharge and 1 month after the last stage 5 seizure, 50 mM KCl induced a significantly larger release of NPY in the stimulated and contralateral hippocampus (P <0.01 and P <0.05), although the effect was less than during kindling. The tissue concentration of NPY increased significantly in both hippocampi at stage 2 and 1 week after stage 5 (2.6 times on average, P <0.01) but no significant differences were found 1 month after stage 5. The present results provide the first evidence of enhanced neuronal release of NPY during kindling, suggesting that this neuropeptide may have a potential role in epileptogenesis.

Original languageEnglish
Pages (from-to)1534-1538
Number of pages5
JournalEuropean Journal of Neuroscience
Volume5
Issue number11
DOIs
Publication statusPublished - 1993

Fingerprint

Neuropeptide Y
Hippocampus
Neurons
Seizures
Implanted Electrodes
Dentate Gyrus
Tetrodotoxin
Neuropeptides

Keywords

  • In vitro release
  • Neuronal plasticity
  • Rat
  • Seizures
  • Sprouting
  • Temporal lobe epilepsy

ASJC Scopus subject areas

  • Neuroscience(all)

Cite this

Electrical kindling of the hippocampus is associated with functional activation of neuropeptide Y-containing neurons. / Rizzi, M.; Monno, A.; Samanin, R.; Sperk, G.; Vezzani, A.

In: European Journal of Neuroscience, Vol. 5, No. 11, 1993, p. 1534-1538.

Research output: Contribution to journalArticle

@article{f1bd262065f942708ade968b0ba90c0c,
title = "Electrical kindling of the hippocampus is associated with functional activation of neuropeptide Y-containing neurons",
abstract = "The release of neuropeptide Y (NPY) was measured from hippocampal slices of rats at stage 2 (preconvulsive stage) and stage 5 (full seizure expression) of electrical kindling of the dorsal hippocampus (upper blade of the dentate gyrus). Spontaneous release in naive rats (9.0±0.8 fmol/ml every 10 min) was independent of external Ca2+ but was reduced by 38±3.6{\%} (P <0.05) during 20 min incubation with 5 μM tetrodotoxin. Spontaneous efflux in naive rats did not differ from that in shams (implanted with electrodes but not stimulated) or in rats kindled to stage 2 and stage 5. Twenty-five, 50 and 100 mM KCl induced a concentration-dependent release of NPY (P <0.05 and P <0.01 at 25 and 50-100 mM respectively) from slices of shams. The effect of 100 mM KCl was reduced by 94±1{\%} (P <0.01) in the absence of Ca2+. Two days after the last stage 2 stimulation and 1 week after the last stage 5 seizure, NPY release was significantly larger than in shams at all KCl concentrations in the stimulated and contralateral hippocampus (P <0.05 and P <0.01). Forty-eight hours after one single after-discharge and 1 month after the last stage 5 seizure, 50 mM KCl induced a significantly larger release of NPY in the stimulated and contralateral hippocampus (P <0.01 and P <0.05), although the effect was less than during kindling. The tissue concentration of NPY increased significantly in both hippocampi at stage 2 and 1 week after stage 5 (2.6 times on average, P <0.01) but no significant differences were found 1 month after stage 5. The present results provide the first evidence of enhanced neuronal release of NPY during kindling, suggesting that this neuropeptide may have a potential role in epileptogenesis.",
keywords = "In vitro release, Neuronal plasticity, Rat, Seizures, Sprouting, Temporal lobe epilepsy",
author = "M. Rizzi and A. Monno and R. Samanin and G. Sperk and A. Vezzani",
year = "1993",
doi = "10.1111/j.1460-9568.1993.tb00222.x",
language = "English",
volume = "5",
pages = "1534--1538",
journal = "European Journal of Neuroscience",
issn = "0953-816X",
publisher = "Wiley-Blackwell",
number = "11",

}

TY - JOUR

T1 - Electrical kindling of the hippocampus is associated with functional activation of neuropeptide Y-containing neurons

AU - Rizzi, M.

AU - Monno, A.

AU - Samanin, R.

AU - Sperk, G.

AU - Vezzani, A.

PY - 1993

Y1 - 1993

N2 - The release of neuropeptide Y (NPY) was measured from hippocampal slices of rats at stage 2 (preconvulsive stage) and stage 5 (full seizure expression) of electrical kindling of the dorsal hippocampus (upper blade of the dentate gyrus). Spontaneous release in naive rats (9.0±0.8 fmol/ml every 10 min) was independent of external Ca2+ but was reduced by 38±3.6% (P <0.05) during 20 min incubation with 5 μM tetrodotoxin. Spontaneous efflux in naive rats did not differ from that in shams (implanted with electrodes but not stimulated) or in rats kindled to stage 2 and stage 5. Twenty-five, 50 and 100 mM KCl induced a concentration-dependent release of NPY (P <0.05 and P <0.01 at 25 and 50-100 mM respectively) from slices of shams. The effect of 100 mM KCl was reduced by 94±1% (P <0.01) in the absence of Ca2+. Two days after the last stage 2 stimulation and 1 week after the last stage 5 seizure, NPY release was significantly larger than in shams at all KCl concentrations in the stimulated and contralateral hippocampus (P <0.05 and P <0.01). Forty-eight hours after one single after-discharge and 1 month after the last stage 5 seizure, 50 mM KCl induced a significantly larger release of NPY in the stimulated and contralateral hippocampus (P <0.01 and P <0.05), although the effect was less than during kindling. The tissue concentration of NPY increased significantly in both hippocampi at stage 2 and 1 week after stage 5 (2.6 times on average, P <0.01) but no significant differences were found 1 month after stage 5. The present results provide the first evidence of enhanced neuronal release of NPY during kindling, suggesting that this neuropeptide may have a potential role in epileptogenesis.

AB - The release of neuropeptide Y (NPY) was measured from hippocampal slices of rats at stage 2 (preconvulsive stage) and stage 5 (full seizure expression) of electrical kindling of the dorsal hippocampus (upper blade of the dentate gyrus). Spontaneous release in naive rats (9.0±0.8 fmol/ml every 10 min) was independent of external Ca2+ but was reduced by 38±3.6% (P <0.05) during 20 min incubation with 5 μM tetrodotoxin. Spontaneous efflux in naive rats did not differ from that in shams (implanted with electrodes but not stimulated) or in rats kindled to stage 2 and stage 5. Twenty-five, 50 and 100 mM KCl induced a concentration-dependent release of NPY (P <0.05 and P <0.01 at 25 and 50-100 mM respectively) from slices of shams. The effect of 100 mM KCl was reduced by 94±1% (P <0.01) in the absence of Ca2+. Two days after the last stage 2 stimulation and 1 week after the last stage 5 seizure, NPY release was significantly larger than in shams at all KCl concentrations in the stimulated and contralateral hippocampus (P <0.05 and P <0.01). Forty-eight hours after one single after-discharge and 1 month after the last stage 5 seizure, 50 mM KCl induced a significantly larger release of NPY in the stimulated and contralateral hippocampus (P <0.01 and P <0.05), although the effect was less than during kindling. The tissue concentration of NPY increased significantly in both hippocampi at stage 2 and 1 week after stage 5 (2.6 times on average, P <0.01) but no significant differences were found 1 month after stage 5. The present results provide the first evidence of enhanced neuronal release of NPY during kindling, suggesting that this neuropeptide may have a potential role in epileptogenesis.

KW - In vitro release

KW - Neuronal plasticity

KW - Rat

KW - Seizures

KW - Sprouting

KW - Temporal lobe epilepsy

UR - http://www.scopus.com/inward/record.url?scp=0027368189&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0027368189&partnerID=8YFLogxK

U2 - 10.1111/j.1460-9568.1993.tb00222.x

DO - 10.1111/j.1460-9568.1993.tb00222.x

M3 - Article

C2 - 8287196

AN - SCOPUS:0027368189

VL - 5

SP - 1534

EP - 1538

JO - European Journal of Neuroscience

JF - European Journal of Neuroscience

SN - 0953-816X

IS - 11

ER -