diabetes mellitus (dm) is one of the most important metabolic disease causes in many side effects. the decrease of mental abilities and even some form of dementia followed prolonged diabetes has been reported. there are evidences that show hippocampus might be the site of neural involvement in patients with dementia followed diabetes. as hippocampus received main serotonergic efferents from bra...

After a single intraperitoneal injection of the irreversible tryptophan hydroxylase inhibitor p-chlorophenylalanine (PCPA; 300 mg/kg), there was a rapid down-regulation of serotonin (5-HT) transporter mRNA levels in cell bodies. This change was significant at 1 and 2 days after PCPA administration within the ventromedial but not the dorsomedial portion of the dorsal raphe nucleus. Seven days af...

The steady-state mRNA levels of the NMDA receptor NR1 subunit were determined by a quantitative solution hybridization assay in selected CNS regions associated with antinociception in the rat. Tissues were obtained by microdissection from rats treated chronically with morphine alone or in combination with LY274614, a competitive NMDA receptor antagonist. Morphine treatment for 7 days resulted i...

Background and Purpose Activation of the defence reaction inhibits baroreflex response via intermediate rostro-ventromedial medulla (B3 raphé) nucleus tractus solitarius (NTS). Our aim was to determine whether how inhibition, induced by disinhibition rostral cuneiform (part pathway), involves 5-HT neurons in B3 5-HT3 receptors NTS. Experimental Approach We performed immunohistochemistry anatomi...

Expression of the immediate-early gene c-fos, a marker of neuronal activation was employed in adult anesthetized non-decerebrate cats, in order to localize the brainstem neuronal populations functionally related to sniff-like (gasp-like) aspiration reflex (AR). Tissues were immunoprocessed using an antibody raised against amino acids of Fos and the avidin-biotin peroxidase complex method. The l...

Recently, a novel cholinergic channel modulator, (R)-5-(2-azetidinylmethoxy)-2-chloropyridine (ABT-594), was shown to produce potent analgesia in a variety of rodent pain models when administered either systemically or centrally into the nucleus raphe magnus (NRM). The purpose of the present study was to investigate the possible supraspinal contribution of ABT-594 by assessing its ability to in...

Several lines of investigations have shown that in some brain areas, in particular, in the midbrain periaqueductal gray matter, rostral ventromedial medulla, central nucleus of amygdala, nucleus raphe magnus, and dorsal hippocampus, microinjections of nonsteroidal anti-inflammatory drugs (NSAIDs) induce antinociception with distinct development of tolerance. The agranular insular cortex (AIC) i...

The mechanisms and sites of action of epibatidine-induced antinociception and side effects are poorly understood. The present study tested the hypothesis that the serotonergic dorsal raphe nucleus is a site of action of epibatidine. Behavioral responses of rats to hindpaw formalin injection were compared after direct administration of epibatidine into the dorsal raphe and after subcutaneous adm...

Background Ketamine rapidly elicits antidepressive effects in humans and mice in which serotonergic activity is involved. Although α4β2 nicotinic acetylcholine receptor (α4β2 nAChR) in the dorsal raphe nucleus plays a key role in the ketamine-induced prefrontal serotonin release, the source of cholinergic afferents, and its role is unclear. Methods Prefrontal serotonin levels after ketamine i...