Introduction: Previously, we demonstrated that i.p. injection of aqueous extract prepared from aerial parts of Drosera Spatulata (Droseraceae) can induced remarkable analgesia in both phases of formalin test in rats. Because, analgesia induced in acute phase of formalin test mainly mediated by activation of central analgesic mechanisms and also paragigantocellularis (PGi) nucleus is part of bra...

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 ...

We used epifluorescence microscopy and a voltage-sensitive dye, di-8-ANEPPS, to study changes in membrane potential during hypercapnia with or without synaptic blockade in chemosensory brain stem nuclei: the locus coeruleus (LC), the nucleus of the solitary tract, lateral paragigantocellularis nucleus, raphé pallidus, and raphé obscurus and, in putative nonchemosensitive nuclei, the gigantocell...

introduction: although tolerance to and dependence on opioids are characterized by excessive activity of camp pathway in some brain stem nuclei, the impact of morphine dependence on activity of camp pathway in paragigantocellularis nucleus (pgi), located in the rostral ventrolateral medulla, remains unclear. therefore, the effect of adenyl cyclase activator forskolin on spontaneous firing rate ...

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...

Stimulation of the nucleus magnocellularis (NMC) of the medulla produces changes in locomotion, muscle tone, heart rate, and blood pressure. Glutamatergic input has been found to modulate muscle tone, whereas cholinergic input has been found to mediate cardiovascular changes produced by stimulation of the NMC. The current study was designed to identify the brainstem afferents to NMC by using re...

Studies have shown that following opiate withdrawal, the spontaneous discharge rate of locus coeruleus (LC) neurons remarkably increases. Combination of intrinsic mechanisms with extrinsic excitatory modulations mediates the withdrawal-induced hyperactivity of LC neurons. The nucleus paragigantocellularis (PGi) provides the main excitatory inputs to LC and plays a pivotal role in opiate withdra...

We have theorized that large neurons in the ventral and medial reticular formation of the medulla are critical for both autonomic and cortical arousal. To test this theory, we anesthetized rats with urethane, lowered concentric bipolar stimulating electrodes into the medullary reticular formation, and implanted electroencephalogram (EEG) and ECG recording electrodes. We stimulated in the medull...

Little is known regarding the descending inhibitory control of genital reflexes such as ejaculation and vaginal contractions. The brainstem nucleus paragigantocellularis (nPGi) projects bilaterally to the lumbosacral motoneuron pools that innervate the genital musculature of both male and female rats. Electrolytic nPGi lesions facilitate ejaculation in males, leading to the hypothesis that the ...