in the present study, the effects of formalin as a peripheral noxious stimulus on spontaneously active units of the nucleus reticularis paragigantocellularis (pgi), a narrow region of the ventral pontine reticular formation, was examined in urethane anesthetized rats. spontaneous discharge of the pgi neurons was variable, ranging from i to 37 spikes per second. formalin as a chemical irritant a...

INTRODUCTION Beside its autonomic functions, the nucleus paragigantocellularis lateralis (LPGi) is involved in the descending pain modulation. 17β-Estradiol is a neuroactive steroid found in several brain areas such as LPGi. Intra-LPGi microinjection of 17β-estradiol can elicit the analgesic responses. 17β-Estradiol modulates nociception by binding to estrogenic receptors as well as allosteric ...

In the present study, the effect of orexin-A (ORXA) microinjection into the paragigantocellularis lateralis (LPGI) on nociceptive behaviors, using hot-plate and formalin tests as thermal and chemical models of pain in rat, was examined. Also, we determined whether the pretreatment with SB-334867, a selective OX1-receptor antagonist, would prevent the antinociceptive effect of orexin-A. ORXA (0....

Introduction: 17β-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 membrane-b...

BNST Bed nucleus of the stria terminalis CCK Cholecystokinin cGMP Cyclic guanosine monophosphate DCN Dorsal central autonomic nucleus fMRI Functional magnetic resonance imaging IML Intermediolateral cell column LCTF Lateral central tegmental field LSt cells Lumbar spinothalamic cells MEA Medial amygdala MPOA Medial preoptic area NO Nitric oxide nPGi Nucleus paragigantocellularis NPY Neuropeptid...

Introduction: The nucleus paragigantocellularis lateralis (LPGi) is involved in the descending pain modulation. The neurostreoid, 17β-estradiol found in the PGi nucleus and modulates nociception by binding to estrogen receptors and also by allosteric interaction with NMDA receptors. In this study, the role of NMDA receptors in the 17β-estradiol-induced pain modulation was investig...

The nucleus paragigantocellularis (PGI) is located in the rostral ventrolateral medulla and has noticeable connections with some other brain nuclei, such as locus ceruleus, nucleus raphe magnus and periaqueductal gray. In rats it is 3 mm in rostrocaudal and 1 mm in mediolateral and 1 mm in the dorsolateral aspect. Anatomically and functionally, PGI has been divided into two subnuclei, retrofaci...

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...

Sexual behavior is suppressed by various types of stressors. We previously demonstrated that an alarm pheromone released by stressed male Wistar rats is a stressor to other rats, increases the number of mounts needed for ejaculation, and decreases the hit rate (described as the number of intromissions/sum of the mounts and intromissions). This deterioration in sexual behavior was ameliorated by...

Introduction: The 17β-estradiol acts as a neurosteroid in the brain and modulates nociception by binding to the estrogen receptors and also by allosteric interaction with other membrane-bound receptors like glutamate receptors. Paragigantocellularis lateralis nucleus (LPGi) is one of the important brain regions implicated in the pain modulation. So, this study was designed to evaluate the ...