Distribution of opioid peptideom RNA and k-opoid receptors in the limbic system of fawn-hooded and wistar-kyoto rats
0
Citation
0
Reference
16
Related Paper
Keywords:
Limbic system
Cite
To compare the distributions of opioid receptor subtypes in central nervous system of spontaneously hypertensive rat (SHR) and normotensive Wistar-Kyoto (WKY) rat.[3H] Ohmefentanyl (OMF), [3H]N-methyl-N-[7-(I-pyrrolidinyl)-1-oxaspiro (4,5)dec-8-yl] benzeneacetamide (U-69593) and [3H]etorphine after suppression of mu and kappa-sites by 15 mumol.L-1 each of unlabeled OMF and trans-(1R,2R)-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl) cyclohexyl]-benzeneacetamide hydrochloride (U-50 488H) were used as ligands for mu, kappa, and delta opioid receptor subtypes in autoradiography, respectively.Delta receptors had an increase in hypothalamic nuclei, periaqueductal gray, caudate and interpeduncular nuclei, and a decrease in substantia nigra in SHR than in those of WKY rat. Mu receptors were less concentrated in basolateral amygdaloid nucleus, habenular nuclei and nucleus of solitary tract of SHR than in those of WKY rats. Kappa receptor density was not checked out in the present study.Distribution of opioid receptor subtypes is related to hypertension of SHR, and delta opioid receptor is more important than mu opioid receptor in the maintenance of hypertension in SHR.
κ-opioid receptor
δ-opioid receptor
μ-opioid receptor
Interpeduncular nucleus
Cite
Citations (4)
Serotonin Agonist
Cite
Citations (25)
5-HT2 receptor
8-OH-DPAT
Cite
Citations (32)
Cite
Citations (14)
Abstract We have previously shown that Fawn‐Hooded (FH) rats reared in isolation display an anxiety‐like phenotype and an enhanced acquisition of ethanol seeking behaviour. Furthermore, antalarmin, a selective corticotrophin‐releasing factor type 1 (CRF 1 ) receptor antagonist, reduces isolation‐induced acquisition and maintenance of volitional ethanol consumption in this strain. The aim of this study was to investigate the ability of CRF 1 receptor antagonism by antalarmin to impact upon brain chemistry in both isolated and group‐housed FH rats. To achieve this, FH rats were reared, from weaning, in either group‐housed or isolation‐housed conditions and at 12 weeks of age were treated with antalarmin (20 mg/kg, i.p; n = 10 per group) or vehicle (1 mL/kg, i.p; n = 10 per group) bi‐daily for ten consecutive days before being killed and their brains removed for neurochemical analyses. Autoradiography and in situ hybridization was employed to analyse changes in the dopaminergic and neurotrophin systems. Isolation rearing increased dopamine D 2 receptor density in the central amygdala and nucleus accumbens, an effect reversed by antalarmin treatment. Conversely, treatment with antalarmin had no impact upon the isolation‐induced alterations of the mRNA encoding brain‐derived neurotrophic factor or the TrkB receptor. Collectively, these findings demonstrate that multiple signalling systems are susceptible to modulation by social isolation and that antalarmin can reverse some, but not all, isolation‐induced alterations in brain chemistry.
Neurochemical
Cite
Citations (61)
Endogenous opioid
Cite
Citations (65)