In acute experiments on anaesthetized with urethane normotensive rats we studied effects of modulating the mitochondrial permeability transition (MPT) of the neurons in the medullary cardiovascular nuclei - nucleus of the tractus solitarius (NTS), paramedian reticular nucleus (PMn), n.ambiguus (AMB), and lateral reticular nucleus (LRN) on the systemic arterial pressure level (SAP). 
In acute experiments on anaesthetized with urethane normotensive rats, we studied the influence of modulation of neuronal NO-synthase (nNOS) activity on the effects of GABA injected in the populations of cardiovascular neurons within the nucleus of tractus solitarius (NTS), n.ambiguus (AMB), paramedian reticular nucleus (PMn) and lateral reticular nucleus (LRN).
Local injection of kainic acid into the paramedian reticular nucleus (PRN) of the medulla oblongata decreased both the spontaneous release of dopamine in the amygdala and spontaneous levels of locomotor activity in rats.
Vasodepressor responses were induced when the caudal ventrolateral medulla, the nucleus tractus solitarius, the lateral tegmental field, the trigeminal nucleus interpolaris, the trigeminal spinal tract, and the paramedian reticular nucleus were stimulated.
Neurones with inclusion bodies occur in the inferior olivary nuclear complex, lateral reticular nucleus, external cuneate nucleus, conterminal nucleus, interfascicular nucleus, nucleus of Roller, dorsal paramedian reticular nucleus, subventricular nucleus, arcuate nucleus, pontobulbar body and pontine grey.
The correlation of the anatomical and clinical findings with those of the MRI are discussed, especially in relation to our understanding of the auditory and vestibular pathways within the brainstem (the auditory striae, the crossed auditory pathways and the nuclei of the corpus trapezoideum for the auditory effects, and the paramedian reticular nucleus and crossed inter-commissure pathways to the cerebellum and vestibular nuclei, together with the proximity of the direct midline vestibulo-spinal tract, for the vestibular effects)..
Results showed that bilateral electrolytic lesions of the red nucleus (RN), the paramedian reticular nucleus (PRN), or the pontine respiratory group (PRG) had little effect on the ability of FN stimulation to modulate the respiratory output.
The brunt of the changes, however, are borne by the pontine gray, the arcuate nucleus, the pontobulbar body, and the paramedian reticular nucleus.
the paramedian reticular nucleus (PRN), were studied in cats anesthetized intraperitoneally with chloralose (40 mg/kg) and urethane (400 mg/kg).
The role of paramedian reticular nucleus (PRN), a structure effecting sympathetic inhibition, in the development of hypertension was investigated in young spontaneously hypertensive rats (SHR) and two age-matched normotensive rats, Wistar-Kyoto (WKY) and Sprague-Dawley rats (SD).
At E20 fibers from Darkschewitsch's nucleus, the paralemniscal and parabrachial nuclei, cell group A5, the locus coeruleus, the gigantocellular reticular nucleus-alpha, the raphe pallidus nucleus, the paramedian reticular nucleus, and from the dorsal medullary reticular nucleus arrived in the lumbosacral cord.
These neurons also projected to the medullary reticular formation, caudal nucleus prepositus hypoglossi, and dorsal and ventral paramedian reticular nucleus.
They projected primarily to the raphe nuclei, the medullary reticular formation, and the paramedian reticular nucleus.
Fastigiofugal fibers which originated from the rostral part of the fastigial nucleus innervated heavily the nucleus reticularis gigantocellularis (NRGc), nucleus reticularis magnocellularis (NRMc) and the ventral paramedian reticular nucleus (PRN).
In contrast, in the paramedian reticular nucleus, noxious heating of the hindpaw resulted in a significant decrease in the mean number of neurons expressing Fos-like immunoreactivity.
Brain sites under exploration included gigantocellular tegmental field and lateral tegmental field (FTG-FTL), the dorsomedial (DM) and ventrolateral (VLM) medulla which produced pressor responses; caudal VLM (CVLM) and paramedian reticular nucleus (PRN) which produced depressor responses.
The brainstem origin of CRF-immunoreactive mossy fiber terminals was suggested by numerous CRF-immunoreactive perikarya located in the medial, lateral and descending vestibular nuclei, nucleus prepositus hypoglossi, nucleus x, paramedian reticular nucleus, gigantocellular reticular nucleus, lateral reticular nucleus, and raphé nuclei. HRP injections into either the posterior vermis or flocculus double labeled CRF-immunoreactive neurons in the paramedian reticular nucleus, nucleus reticularis gigantocellularis, and raphé nuclei.
Depressor and bradycardiac response to stimulation of paramedian reticular nucleus or dorsal motor nucleus of vagus (DMV) decreased significantly as well.
Activation of the paramedian reticular nucleus, which consistently produced depressor responses, and activation of raphe nuclei, which produced depressor or pressor responses, consistently decreased UB motility.
Either intact rats, sham-operated rats, or rats with lesions of the paramedian reticular nucleus (PRN) were exposed to cold (2 degrees C) or heat (36 degrees C) stress and their locomotor activity responses and striatal dopamine (DA) release were compared.
The effects of stimulation of the paramedian reticular nucleus (PRN) in the rat medulla oblongata on both amphetamine-induced locomotor activity and striatal release of dopamine-like material were assessed.
All the afore-mentioned activity measures induced by amphetamine were suppressed following electrolytic lesions of the paramedian reticular nucleus (PRN) in rat medulla.
In other groups the paramedian reticular nucleus (PRN) was intermittently stimulated to inhibit the sympathetic nervous system.
Effects of activation of paramedian reticular nucleus (PRN) on the systemic arterial blood pressure (SAP), heart rate, renal nerve activity (RNA), and changes of the partial pressure of the arterial blood oxygen (PO2) and carbon dioxide (PCO2) during asphyxia were studied in cats anesthetized with chloralose (40 mg/kg) and urethane (400 mg/kg).
The inhibition was not affected after bilateral electrolytic- or kainic-acid-induced lesions in the paramedian reticular nucleus (PRN).
The data generated by these cell counts indicate that the strongest reticulocerebellar projections arise from the three specialized pre-cerebellar reticular nuclei: the lateral reticular nucleus, the medullary paramedian reticular nucleus, and the reticulotegmental nucleus.
Anatomical connections of the paramedian reticular nucleus (PRN) of the caudal medulla were investigated using a bi-directional tracer, horseradish peroxidase (HRP).
Pressor areas of the dorsal medulla (DM) and ventrolateral medulla (VLM) and the depressor area of the paramedian reticular nucleus (PRN) were stimulated electrically using a monopolar electrode, or chemically using sodium glutamate microinjection.
Serotoninergic fibers in the anterior vermis (lobules I-V) were shown to arise from neurons located within the paramedian reticular nucleus, the lateral reticular nucleus, and the lateral tegmental field. Lobus simplex, crus I and crus II (the hemisphere) receive a serotoninergic input from cells located in the lateral tegmental field, the peri-olivary reticular formation and the paramedian reticular nucleus.
Retrogradely labeled cells were observed in the lateral tegmental field (FTL), paramedian reticular nucleus, magnocellular reticular nucleus (Mc), in the gigantocellular nucleus (Gc), lateral reticular nucleus (LR), lateral paragigantocellular nucleus (PGL), rostral ventrolateral medullary reticular formation (RVR), as well as in the medullary raphe nuclei following the injection of the tracer substance(s) into various levels of the spinal cord. The FTL, the ventral portion of the paramedian reticular nucleus (PRv), Mc, LR, PGL and the raphe nuclei were found to project to thoracic, lumbar and sacral spinal segments. The dorsal portion of the paramedian reticular nucleus (PRd), Gc and the RVR projected mainly to thoracic segments.
Retrogradely labeled neurons were observed in the gigantocellular reticular nucleus (GRN), the pontine reticular nucleus of the pons (PON), the ambiguus nucleus (AN) and the paramedian reticular nucleus (PRN).
Previous studies have shown that paramedian reticular nucleus (PRN) possessed sympathetic and parasympathetic inhibitions on autonomic nervous system.
The effects of stimulation or ablation of the paramedian reticular nucleus (PRN) of the rat medulla oblongata on the thermal responses induced by ambient temperature changes, a pyrogen, or a hypothermic substance were assessed.
The inhibitory actions of the paramedian reticular nucleus (PRN), and its neighbouring structures, i.e., midline raphe nuclei (MRN) and dorsal medullary depressor area (DMD) on the knee jerk (KnJ) and crossed extension movement (CEM) induced by central sciatic stimulation and on the L5 ventral root response (EVRR) evoked by central tibial stimulation, were studied in cats under urethane (400 mg/kg) and alpha-chloralose (40 mg/kg) anesthesia alone, IP or further paralyzed with atracurium besylate (0.5 mg/kg/30 min), IV.
Such nuclei include the lateral cuneate nucleus, the nucleus prepositis hypoglossi, the nucleus reticularis lateralis, the nucleus raphe obscurus, the paramedian reticular nucleus, the nucleus reticularis gigantocellularis, and the medial vestibular nucleus.
We examined whether the dorsolateral pontine cholinergic cells project to the paramedian reticular nucleus (PRN) of the caudal medulla.
In 5 successful experiments, the HRP-labeled cells were bilaterally distributed in the para-ambiguus nucleus (59.0%), ventral subnucleus of the paramedian reticular nucleus (13.6%), and raphe nuclei (10.8%).
The paramedian reticular nucleus (PRN) is a triangle midline structure located in the caudal medulla.
CRF-IR neuronal cell bodies are prominent within several brainstem nuclei known to project to the cerebellum: all divisions of the inferior olivary complex, the lateral reticular nucleus, paramedian reticular nucleus, gigantocellular reticular nucleus, raphe nuclei, perihypoglossal complex, medial and inferior vestibular nuclei and cell groups f and x, locus ceruleus, and nucleus subceruleus.
The organization of host-graft interactions was studied by autoradiography of anterogradely transported tritiated leucine, injected in the host bulbar region containing the caudal half of the inferior olivary complex (origin of all vermal climbing fibres) and the dorsally adjacent paramedian reticular nucleus (origin of a few mossy fibres).
The neurons in the paramedian reticular nucleus and the pontine nuclei proper appear to project only to the cerebellar cortex..
The depressor and bradycardia responses elicited from electrical stimulation of the paramedian reticular nucleus (PRN) (which exerts both sympathetic and parasympathetic inhibitions) or from the area of the solitary nucleus/dorsomotor nucleus of vagus (NTS/DMV) (where stimulation leads to both parasympathetic activation and sympathetic inhibition) were also more intensive in SHR than in WKY and SD.
Experiments were done in chloralose-anesthetized cats to identify single units in the paramedian reticular nucleus (PRN) that responded to stimulation of pressor sites in the vestibular nucleus complex (VNC) and that projected directly to the intermediate gray (IG) region of the upper thoracic cord.
In chloralose anesthetized, paralyzed and artificially ventilated cats, the region of the paramedian reticular nucleus (PRN) was systematically explored for single units antidromically activated by electrical stimulation of histologically verified sites in the intermediate gray region of the upper thoracic cord (T2).
Inhibitory actions of the medial trigon of the caudal medulla (ITM) with special reference to the paramedian reticular nucleus (PRN) were explored in cats under chloralose (40 mg/kg) and urethane (400 mg/kg) anesthesia.
In cats, the resting systemic arterial blood pressure (SAP) which rises on electrical stimulation of the dorsal medulla (DM), ventrolateral medulla (VLM) and paramedian reticular nucleus (PRN) under anesthesia with 2% halothane in oxygen were compared with those 30 min after termination of the inhalation (with application of lidocaine on the surgical wound and i.v.
Experiments were done in cats to identify neurons in the paramedian reticular nucleus (PRN) sending collateral axons to the region of the intermediolateral nucleus (IML) at different levels of the thoracic cord by using lectin-conjugated horseradish peroxidase (HRP) and double-labeling fluorochrome histochemistry to retrogradely label PRN neurons.
Lesions in the paramedian reticular nucleus, rostral and caudal to obex, failed to reduce the FN cardiovascular response.
The topographic organization of afferent projections from the deep cerebellar nuclei, medulla oblongata and spinal cord to the paramedian reticular nucleus (PRN) of the cat was studied using the horseradish peroxidase (HRP) method of retrograde labelling.
Subsequent to injections of HRP into the vermis and immediately adjacent portions of the cerebellar cortex, several reticular and raphe nuclei (n.) were found to project to the cerebellum including the paramedian reticular nucleus, n.
Injections of combined lectin-conjugated and unconjugated horseradish peroxidase were made in the dorsal (d) and ventral (v) divisions of the paramedian reticular nucleus (PRN), a precerebellar relay nucleus, of the cat.
Injections of fluorescent tracers into cat cerebellar cortex gave evidence of collateral axonal branching of neurons situated in the paramedian reticular nucleus.
Low concentrations of ir-alpha-neo-endorphin (less than 100 fmol/mg of protein) are found in many cortical structures, claustrum, thalamic nuclei, habenular nuclei, lateral geniculate body, red nucleus, superior and inferior colliculi, paramedian reticular nucleus, pontine nuclei, superior olive, vestibular nuclei, motor facial nucleus, gigantocellular reticular nucleus, and subfornical organ..
Label was found in the nucleus reticularis ventralis, lateral reticular nucleus, nucleus gigantocellularis, nucleus pontis caudalis and the paramedian reticular nucleus.
(3) Medullary reticular formation--the strongest projection of mossy fibers arises from the accessory group of the paramedian reticular nucleus.
However, in the external cuneate nucleus and in the paramedian reticular nucleus there was a decrease in glucose utilization.
Neurons in the interpositus nucleus (IP) were activated antidromically from the nucleus reticularis tegmenti pontis (NRTP) and paramedian reticular nucleus (PMRN).
Acetylcholine microinjections into the ventricular reticular nucleus was accompanied by more marked changes in the activity of the splenic nerve, whereas stimulation of the paramedian reticular nucleus affected to a greater measure the renal nerve..
They were distributed over 5 medullary nuclei: (1) nucleus of the solitary tract (NTS); (2) paramedian reticular nucleus (NPR); (3) perihypoglossal nucleus (PXII); (4) lateral tegmental field (FTL); and (5) nucleus ambiguus.
Details in the cerebellar projections from the paramedian reticular nucleus (PRN) were studied in cats and monkeys by means of retrograde axonal transport of horseradish peroxidase (HRP).
The conditioning stimulation of lateral or paramedian reticular nucleus was found to reduce polysynaptic activation of DSCT cells (type 3 response) selectively without affecting either the spontaneous background discharge or the monosynaptic activation (type 1 response) or inhibition (type 2 response) by afferent inputs from the peripheral nerves of hindleg.
No evidence for a projection of sinus nerve afferents to the medial reticular formation (an area extending medially from the hypoglossal nucleus and nerve tract and including the paramedian reticular nucleus) was obtained in either antidromic or orthodromic studies.
Neurones in the paramedian reticular nucleus of decerebrate, unanaesthetised cats have been identified by microelectrode recording combined with antidromic activation of their axons in the ipsilateral inferior cerebellar peduncle. The paramedian reticular nucleus appears to be a relatively homogeneous group of neurones, pharmacologically as well as anatomically..
The projection from the NTS is to the nucleus ambiguus (A), the other divisions of the NTS including the medial NTS and the ventrolateral NTS, and DNV, the medial reticular formation ventral to the NTS (probably the paramedian reticular nucleus), the nucleus intercalatus (INC), and the intermediate nucleus (INT).
In decerebrate cats neurones in the region of the paramedian reticular nucleus were identified by responses to stimulation of implanted cerebellar electrodes.
The nature of the responses of cells of the paramedian reticular nucleus and of the perihypoglossal nuclei to electrophoretically applied acetylcholine (ACh) was investigated.
Furthermore, the slow wave was aborted by stimuli delivered to the baroreceptor nerves or paramedian reticular nucleus during a time span which accounted for less than 1 percent of the cardiac cycle.
Twelve carotid baroreceptor neurones were identified, in thirty-three cats, nine of which were localized in the intermediate area of the nucleus of the solitary tract (NTS) within 1 mm ahead of or behind the obex; three units were located either in the parahypoglossal area or the dorsal portion of the paramedian reticular nucleus (PRN).3.
Bilateral electrolytic lesions of the paramedian reticular nucleus abolished both the FPR and the CSN depressor response without altering base line pressure.5. With micro-electrode recording neurones were discovered within the paramedian reticular nucleus which responded to electrical stimulation of the FN or the CSN. The interaction between the FN and the CSN projections to the paramedian reticular nucleus was examined by conditioning-test studies. The paramedian reticular nucleus appears to be an important site for the interaction.8.
Selective electrical stimulation of the paramedian reticular nucleus (PRN) in anaesthetized and decerebrate-anaesthetized cats elicited cardiac slowing which was shown to be due to inhibition of the sympathetic input to the heart.2.
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