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: nucleus reticularis paragigantocellularis (pgi) is one of the major components of the rostral ventromedial medulla (rvm), which is involved in nociceptive processing and pain modulation. the aim of this study was to examine the effect of c fiber destruction on responsiveness of nucleus reticularis paragigantocellularis (pgi) to formalin, as a noxious stimulus, in normal and morphi...

The distribution of reticulocerebellar (RC) neurons was examined by the retrograde transport of horseradish peroxidase (HRP) or wheat germ agglutinin bound to HRP (WGA-HRP) in 7 White Leghorn chickens. A large number of labeled cells were found in the nucleus reticularis pontis caudalis (RP) of the pontomedullary junction and in the nucleus reticularis gigantocellularis (Rgc), parvocellularis (...

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 irrita...

  In the present study, the effect of contralateral and bilateral electrolytic lesions of the nucleus reticularis paragigantocellularis (PGi) on tonic pain was assessed in rats. Pain-related behavior was evaluated using the formalin test 7 days after the lesion was made. PGi lesions did not produce any marked changes in the early phase of the formalin test, but significantly increased pain sens...

This is a review of research aimed at elucidating how various opiate analgesia substrates in rat brain stem interact with one another to bring about opiate analgesia. The three substrates studied are the midbrain periaqueductal grey (PAG), the bulbar nucleus raphe magnus (RM), and the bulbar nucleus reticularis paragigantocellularis (PGC). The methods used in the reviewed studies are unique in ...

The immunocytochemical distribution of [Leulenkephalin and an adrenal enkephalin precursor fragment (BAM-22P) immunoreactivity was investigated in the diencephalon and brainstem of rats pretreated with relatively high doses of colchicine (300-400 pgil0 pl intracerebroventricularly). The higher ranges of colchicine pretreatment allowed the visualization of extensive enkephalincontaining systems ...

introduction: in this study the effect of matricaria recutita extract on acute pain in the presence and absence of flumazenil (antagonist of benzodiazepine) and lesioned paragigantocellularis (pgi) nucleus was investigated. method: wistar male rats (250±20 g) were used. animals were grouped randomly into intact, sham and bilateral lesion of pgi nucleus. intact and lesioned animals, each divided...