Effect of repeated electroconvulsive treatment on regional concentrations of tachykinins, neurotensin, vasoactive intestinal polypeptide, neuropeptide Y, and galanin in rat brain

Abstract

The effects of single and repeated electroconvulsive treatments (ECTs) on brain regional distribution of substance P (SP), neurokinin A (NKA), neurotensin (NT), neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP), and galanin (GAL) were studied in the rat. Rats were divided into four groups receiving one of the following treatments: one ECT, one sham ECT, six ECTs, or six sham ECTs. After sacrifice by focused microwave irradiation, brains were dissected into frontal cortex, striatum, occipital cortex, hippocampus, hypothalamus, and pituitary sections. Peptides were extracted by boiling the tissues in 1 mol/l acetic acid and measured in extract aliquots by specific radioimmunoassays. Marked regional differences (P = .0005) were found for each of the peptides measured. The highest concentrations of SP and NKA were found in the hypothalamus and, in descending order, in striatum, pituitary, frontal cortex, occipital cortex, and hippocampus. For NT, the highest level was found in the hypothalamus and, in descending order, in pituitary, striatum, hippocampus, frontal cortex, and occipital cortex. The highest VIP concentrations were measured in frontal and occipital cortex, followed by pituitary, hypothalamus, striatum, and hippocampus. The highest NPY and GAL concentrations were found in the hypothalamus and the pituitary; in frontal and occipital cortex, as well as in the striatum and hippocampus, the peptides levels were rather evenly distributed. Repeated handling (stress?) decreased both NT and GAL in frontal (P = .05 and .04) and occipital cortex (P = .09 and .07). ECT, one or six treatments, had no effect on SP, NKA, NT, VIP, or GAL concentrations in different brain regions. However, an increase in NPY concentrations in hippocampus (six sham ECTs vs.(ABSTRACT TRUNCATED AT 250 WORDS)

Plasticity in Hippocampal Peptidergic Systems Induced by Repeated Electroconvulsive Shock

“…Hippocampal levels of other amidated neuropeptides (e.g. substance P, vasoactive intestinal polypeptide and galanin) are unaffected by repeated ECS (Stenfors et al 1989;Mathe 1999). The cumulative increases in PAM protein in the hippocampus after repeated ECS suggest major roles for amidated peptides in the response to ECT, for example as autocrine growth factors.…”

“…Increased PAM immunoreactivity in CA1-3 pyramidal cells suggests a role for amidated peptides like CCK, which is expressed in pyramidal cell neurons (Sloviter and Nilaver 1987;Stengaard-Pedersen et al 1983). ECS increases levels of several amidated peptides including TRH, EEP (pGlu-Glu-Pro-NH 2 ; Single letter code for Glu ϭ E, Pro ϭ P), neurokinin and CCK (Kubek et al 1985;Stenfors et al 1989;Orzi et al 1990;Mathe 1999;Pekary et al 1999Pekary et al , 2000. Hippocampal levels of other amidated neuropeptides (e.g.…”

“…Changes in a variety of neuropeptides and peptide growth factors are associated with depression (Kubek et al 1985;Widerlöv et al 1986;Kanamatsu et al 1986;Stenfors et al 1989;Orzi et al 1990;Zetterstrom et al 1998;Mathe 1999;Pekary et al 1999Pekary et al , 2000. For example, depressed patients have decreased levels of cerebrospinal fluid neuropeptide Y (NPY) (Widerlöv et al 1986(Widerlöv et al , 1988Gjerris et al 1992).…”

Topiramate Normalizes Hippocampal NPY-LI in Flinders Sensitive Line ‘Depressed’ Rats and Upregulates NPY, Galanin, and CRH-LI in the Hypothalamus: Implications for Mood-Stabilizing and Weight Loss-Inducing Effects

“…The supernatants were lyophilized and reconstituted in phosphate buffer prior to RIA. RIA was performed using antibodies specific for NPY (RIN7180, Peninsula Laboratories, USA), CRH (a generous gift from Dr P Lowry (Linton and Lowry, 1986)), and galanin (GAL4, a generous gift from Dr E Theodorsson (Stenfors et al, 1989)). Within each experiment, all samples from a given brain region were analyzed in triplicate in the same run.…”

“…Furthermore, treatment modalities used in the therapy of mood disorders, i.e. antidepressants and electroconvulsive stimulations (ECS, an experimental model of ECT), enhance NPYergic neurotransmission in rats (Jiménez Vasquez et al, 2000;Husum et al, 2000;Mathé et al, 1998;Stenfors et al, 1989;Widdowson and Halaris, 1989). These observations support the hypothesis that NPY plays a role in the pathogenesis as well as the alleviation of mood disorders.…”