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Immunohistochemical evidence indicates the coexistence of serotonin and TRH in many raphe neurons. We examined the biochemical changes in TRH receptors after destruction of the serotonergic pathways by 5,7-dihydroxytryptamine (5,7-DHT). 2 weeks after an intracerebroventricular injection of 5,7-DHT, rats were killed, and specific brain regions were dissected(More)
The effect of acute cold-restraint stress on binding of [3H]rauwolscine to alpha 2-adrenoceptors was investigated in 10 regions of rat brain. Acute stress: significantly decreased the density but had no significant effect on the affinity of binding sites in the hippocampus; decreased density and increased affinity in the amygdala; and increased density and(More)
The anti-depressive effects of thyrotropin releasing hormone (TRH) and its analogues (DN-1417: gamma-butyrolactone-gamma-carbonyl-histidyl-prolinamide citrate; MK-771: L-pyro-2-aminoadipyl-histidyl-thiazolidine-4-carboxamide) were examined in behavioral despair rats, an animal model of depression. TRH, DN-1417, MK-771, amitriptyline and diazepam were(More)
Vasoactive intestinal polypeptide (VIP) interaction with the rat brain synaptic membrane was examined using 125I-labeled VIP as a tracer molecule. Ion, pH and incubation time significantly influenced VIP receptor binding. Scatchard analysis suggested that the rat brain membrane had a single binding site with an apparent dissociation constant (Kd) of 9.8 X(More)
Cerebrospinal fluid gamma-aminobutyric acid (CSF-GABA) was analysed by radioreceptor assay in 16 normal controls and 84 patients with various neurological and psychiatric diseases. In patients with spinocerebellar degeneration, neuro-Behçet's syndrome and Parkinson's disease, CSF-GABA levels were decreased. On the other hand, increased CSF-GABA levels were(More)
Characteristics of TRH-receptors were studied in the rat central nervous system (CNS). Ion species, pH and temperature importantly influenced TRH-receptor binding. Subcellular distribution of TRH-receptor binding revealed that synaptic membranes had the greatest percentage of total sites. Scatchard analysis suggested that the rat CNS had two distinct TRH(More)
Flunarizine hydrochloride (FZ) is used to improve cerebral circulation and possesses Ca antagonistic effects. In recent years, this drug has been reported to induce parkinsonism and depressive symptoms as side effects, particularly in the elderly. Effects of FZ on dopamine receptors of the rat striatum were studied by radiolabeled receptor assay to clarify(More)
Displacement curves of the beta-adrenergic agonist (-)-isoproterenol, on the binding of [3H]-dihydroalprenolol (DHA) in homogenates from the brain of rat defined a two-site model of high (KH; 8.5 +/- 1.6 nM) and low (KL; 771 +/- 111 nM) affinity. The KL/KH ratio was 84.5 +/- 4.5. Somatostatin, ACTH, dynorphin and mastoparan, but not vasoactive intestinal(More)
Cerebral cortical slices from rat brain were incubated at 37 degrees C for 2 h in the presence of isoproterenol, noradrenaline, or adrenaline, and binding affinities and densities of adrenoceptor subtypes were subsequently examined in homogenized tissue. The density of alpha 2- and total beta-adrenoceptors was estimated using the radioligands(More)
Radioreceptor assay (RAA) results in rat brain with 3H-nicotine were compared with those obtained using 125I-alpha-Bungarotoxin (BTX). Scatchard analysis showed that the 3H-nicotine binding site had an average Kd and Bmax of 5.31 nM and 0.047 p moles/mg protein, respectively, and that the corresponding 125I-alpha-BTX binding site values were 0.092 nM and(More)