introduction: drugs of abuse such as nicotine and morphine used systemically by addicts produce their effects via the mesolimbic dopaminergic pathway. furthermore, evidence indicates that some behavioral effects of nicotine and morphine are mediated by nitric oxide (no). based on these observations, the aim of the present study was to investigate the effects of intra-nucleus accumbens (nac) inj...

introduction: gonadotropin inhibitory hormone (gnih) and agouti-related peptide (agrp) are orexigenic peptides expressed in the arcuate nucleus (arc) of the hypothalamus in the ewe. in addition, effects of gnih and agrp on the regulation of gonadotropin releasing hormone secretion have been shown in some mammals. the objective of the present study was to investigate the coexpression of gnih and...

the parafascicular nucleus (pfn) of thalamus, as a supraspinal structure, has an important role in processing of nociceptive information. in addition, μ-opioid receptor contributes to supraspinal modulation of nociception. in the present study, the effects of microinjection of naloxone (a non-specific opioid-receptor antagonist) and naloxonazine (a specific μ-opioid receptor antagonist) were in...

background: spine of an adult is made up of five areas that include 7 cervical vertebrae, 12 thoracic vertebrae, 5 lumbar vertebrae, sacrum and finally coccyx. selecting appropriate assumptions for modeling and biological analysis of the spine components has a significant impact on the accuracy of results in biomechanical simulation for different modes. methods: in the present study, biomechani...

the effects of formalin as a peripheral noxious stimulus on the activity of lateral paragigantocellularis nucleus (lpgi) neurons were examined. spontaneous activity oflpgi neurons was recorded after confirmation of their responsiveness to acute pain, and thereafter formalin (50 µl, 2.5%) was injected in the contralateral hindpaw. the response of the lpgi neurons was monitored for 60 min. a biph...

introduction: 17&beta-estradiol; modulates nociception by binding to the estrogenic receptors and also by allosteric interaction with other membrane-bound receptors like glutamate and gabaa receptors. in addition to its autonomic functions, paragigantocellularis lateralis (lpgi) is involved in the pain modulation, too. the aim of the current study was to investigate the involvement of the membr...

introduction: in this study, the effect of memantine administration into the nucleus accumbens on the metabolic changes induced by acute stress in female mice was evaluated. methods: intra-accumbens unilateral or bilateral canulation was performed. one week after recovery, a group of animals were given memantine (1, 0.5, and 0.1 μg/mouse) five min before stress induction intra-accumbally, and t...

introduction: although formalin-induced activity in primary afferent fibers and spinal dorsal ‎horn is well described, the midbrain neural basis underlying each phase of behavior in ‎formalin test has not been clarified. the present study was designed to investigate the nucleus ‎cuneiformis (cnf)‎‏ ‏neuronal responses during two phases after subcutaneous injection of ‎formalin into the hind paw...

the catastrophic effects of opioids use on public health and the economy are documented clearly in numerous studies. repeated morphine administration can lead to either a decrease (tolerance) or an increase (sensitization) in its behavioral and rewarding effects. morphine-induced sensitization is a major problem and plays an important role in abuse of the opioid drugs. studies reported that mor...