Parabrachial complex glutamate receptors modulate the cardiorespiratory response evoked from hypothalamic defense area.

To characterize the possible role of glutamate in the interaction between Hypothalamic Defense Area (HDA) and Parabrachial complex (PBc) nuclei, cardiorespiratory changes were analyzed in response to electrical stimulation of the HDA (1 ms pulses, 30-50 µA given at 100 Hz for 5s) before and after the microinjection of the nonspecific glutamate receptor antagonist kynurenic acid (50 nl, 5 nmol), NMDA receptor antagonist MK-801 (50 nl, 50 nmol), non-NMDA receptor antagonist CNQX (50 nl, 50 nmol) or metabotropic glutamate receptor antagonist MCPG (50 nl, 5 nmol) within the PBc. HDA stimulation evoked an inspiratory facilitatory response, consisting of an increase in respiratory rate (p<0.001) due to a decrease in expiratory time (p<0.01). The respiratory response was accompanied by a pressor (p<0.001) and a tachycardic response (p<0.001). Kynurenic acid within the lateral parabrachial region (lPB) abolished the tachycardia (p<0.001) and decreased the magnitude of blood pressure response (p<0.001) to HDA stimulation. Similarly, the magnitude of the tachycardia and the pressor response was decreased after the microinjection of MK-801 (p<0.01 and p<0.001, respectively) and CNQX (p<0.05 in both cases) into the lPB. Kynurenic acid microinjection in this region produced an inhibition of the tachypnea (p<0.001) to HDA stimulation but the respiratory response persisted unchanged after MK-801 or CNQX microinjection into the lPB. Kynurenic acid within the medial parabrachial region (mPB) abolished the tachycardia (p<0.01) and decreased the magnitude of the pressor response (p<0.001) to HDA stimulation. MK-801 and CNQX microinjection in this region decreased the magnitude of the tachycardia (p<0.05, in both cases) and pressor response (p<0.05, in both cases). The respiratory response evoked by HDA stimulation was not changed after the microinjection of kynurenic acid, MK-801 or CNQX within the mPB. No changes were observed in the cardiorespiratory response evoked to HDA stimulation after MCPG microinjection within lPB and mPB. These results indicate that glutamate PBc receptors are involved in the cardiorespiratory response evoked from the HDA. The possible mechanisms involved in these interactions are discussed.

Prevalencia y comorbilidad de síntomas neuropsiquiátricos en la enfermedad de Alzheimer / Prevalence and comorbidity of neuropsychiatric symptoms in Alzheimer's disease

Introducción. Se describe la frecuencia y gravedad de los síntomas conductuales y psicológicos (SCP) en un grupo de125 pacientes diagnosticados con enfermedad de Alzheimer(EA) siguiendo criterios diagnósticos DSM-IV-TR y NINCDSADRDA. Metodología. La evaluación de los SCP se realizó mediante el Neuropsychiatric Inventory (NPI; Cummings et al., 1994). Se recogieron los datos sociodemográficos y antecedentes personales de los pacientes y se estableció el estadio de la demencia mediante la Global Deterioration Scale (GDS; Reisberg, 1982). Resultados. Un total de 122 pacientes (98%) presentaron SCP, con una media de cinco síntomas por paciente. La frecuencia de su presentación fue la siguiente: apatía (75%), irritabilidad (66%), depresión (60%), agitación (55%), ansiedad (54%), actividad motora aberrante (47%), delirios (38%), alteraciones del sueño (36 %), desinhibición (29 %), alteraciones del apetito (28%), alucinaciones (20%) y euforia (4%). Conclusiones. Estos resultados demuestran la alta incidencia de los SCP en los pacientes con EA y muestran la necesidad e importancia de tratar adecuadamente estas alteraciones (AU)

Introduction. The objective of this study is to describe the frequency and severity of behavioral and psychological symptoms (BPS) in a group of 125 patients diagnosed of Alzheimer’s disease (AD) (DSM-IV-TR and NINCDSADRDA criteria). Methods. The evaluation of the BPS was carried out using the Neuropsychiatric Inventory (NPI; Cummings et al., 1994). The sociodemographic and personal background data of the patients were gathered and the dementia stage was established with the Global Deterioration Scale (GDS Reisberg, 1982). Results. A total of 122 patients (98%) presented BPS, with an average of five symptoms per patient. Frequency of presentation was the following: apathy (75%), irritability (66 %), depression (60 %), agitation (55 %), anxiety (54 %), aberrant motor activity (47 %), delirium (38 %), sleeping disorders (36%), disinhibition (29%), eating disorders (28%), hallucinations (20%) and euphoria (4%). Conclusions. These results show the high incidence of BPS in AD patients and point to the necessity and importance of treating these disorders appropriately (AU)

Perfil clínico de pacientes con enfermedad de Alzheimer atendidos en centros de día psicogeriátricos / Clinical profile of patients with Alzheimer´s disease attended at psychogeriatric day centers

Objetivo: Describir las características sociodemográficas,perfil cognitivo, estado funcional y síntomas conductualesy psicológicos (SCP) en 125 pacientes conenfermedad de Alzheimer (EA), así como la carga desus cuidadores.Material y métodos: Se recogieron datos sociodemográficosy clínicos y se evaluaron: estadio de la demencia(Global Deterioration Scale), cognición (Mini Mental StateExamination/MMSE, Fluencia Verbal Semántica yFonológica, Rey Auditory Verbal Learning Test y TrailMaking Test), estado funcional (Bayer Activities of DailyLiving/B-ADL), SCP (Neuropsychiatric Inventory) y cargadel cuidador (atención a las actividades básicas de la vidadiaria/ABVD, Hamilton Depression Rating Scale/HDRS,State-Trait Inventory/STAI y subescala de sufrimiento delNeuropsychiatric Inventory).Resultados: El 70%de los pacientes eran mujeres (edadmedia: 76 años), con un tiempo de evolución de la demenciade 62 meses. Sufrían un deterioro cognitivo moderado(MMSE: 14,46 ± 4,81), un deterioro funcional moderado/grave (B-ADL: 8,92 ± 1,31). El 98% presentaron SCP.El 79% de los cuidadores fueron mujeres (edad media: 61años), dedicaban 2,34 ± 1,61 horas diarias a la atención deABVD. Presentaban niveles elevados de ansiedad (STAI:35,59 ± 7,05) y depresión (HDRS: 14,28 ± 6,66).Conclusiones: Nuestros resultados indican que lospacientes con EA atendidos en centros de día psicogeriátricosson mayoritariamente mujeres, con un deteriorocognitivo y funcional moderadamente graves y conuna elevada frecuencia de SCP. Sus cuidadores principalespresentan síntomas de ansiedad y depresión

Objective: The objective of this study is to describethe socio-demographic data, cognitive profile, functionalstatus and behavioral and psychological symptoms(BPS) in a group of 125 patients diagnosed withAlzheimer’s disease (AD), as also the burden and distressof their caregivers.Material and methods:We collected socio-demographicand clinical data and assessment: stage of dementia(Global Deterioration Scale), cognitive functions (MiniMental State Examination/MMSE, Semantic and PhonemicVerbal Fluency, Rey Auditory Verbal Learning Testand Trail Making Test), activities of daily living (BayerActivities of Daily Living/B-ADL), BPS (NeuropsychiatricInventory) and caregiver’s burden (number of hoursof attention given to the basic activities of dailyliving/BADL, Hamilton Depression Rating Scale/HDRS,State-Trait Inventory /STAI and NPI-distress Scale).Results: 70% of patients were women (mean age: 76years old), with a mean time of dementia of 62 months.They had a moderate cognitive impairment (MMSE:14.46 ± 4.81) and a severe functional deterioration (BADL:8.92 ± 1.31). A total of 122 patients (98%)showed BPS. 79% of caregiver were women (mean age:61 years old), dedicating an average of 2.34 hours toattend to the BADL, with a high level of anxiety (STAIE:35.59 ± 7.05) and depression (HDRS: 14.28 ± 6.66).Conclusions: The AD patients who attend the psychogeriatricday centers are mainly women, with moderatelysevere cognitive and functional impairment andwith high frequency of BPS. Their main caregiversshow symptoms of anxiety and depression

[Prevalence and comorbidity of neuropsychiatric symptoms in Alzheimer's disease]. / Prevalencia y comorbilidad de síntomas neuropsiquiátricos en la enfermedadde Alzheimer.

INTRODUCTION: The objective of this study is to describe the frequency and severity of behavioral and psychological symptoms (BPS) in a group of 125 patients diagnosed of Alzheimer's disease (AD) (DSM-IV-TR and NINCDSADRDA criteria). METHODS: The evaluation of the BPS was carried out using the Neuropsychiatric Inventory (NPI; Cummings et al., 1994). The sociodemographic and personal background data of the patients were gathered and the dementia stage was established with the Global Deterioration Scale (GDS Reisberg, 1982). RESULTS: A total of 122 patients (98%) presented BPS, with an average of five symptoms per patient. Frequency of presentation was the following: apathy (75%), irritability (66%), depression (60%), agitation (55%), anxiety (54%), aberrant motor activity (47%), delirium (38%), sleeping disorders (36%), disinhibition (29%), eating disorders (28%), hallucinations (20%) and euphoria (4%). CONCLUSIONS: These results show the high incidence of BPS in AD patients and point to the necessity and importance of treating these disorders appropriately.

5-HT1A receptor activation before acute stress counteracted the induced long-term behavioral effects.

The long-term behavioral consequences of acute immobilization (IMMO) in rats and the effects of 5-HT(1A) receptor activation (8-OH-DPAT: 0.3 mg/kg, sc) were studied. Corticosterone levels after IMMO with previous 8-OH-DPAT treatment were also studied. Twenty-four hours after IMMO (3 h), rats performed conditioned (passive avoidance) and unconditioned (escape behavior) anxiety tests in the elevated T maze. Pre-exposure to IMMO induces long-term behavioral changes in contrast with control rats. These behavioral alterations include an increase of anxiogenic responses, such as exploratory behavior and passive avoidance response. This effect was counteracted by 8-OH-DPAT pretreatment and reversed by WAY-100635 when administered before 8-OH-DPAT. Serum corticosterone levels increased during the first hour of stress and after 8-OH-DPAT administration. Our results support the hypothesis that involvement of acute stress is crucial in the anxiety-like behaviors and in the potentiation of fear. The activation of 5-HT(1A) receptors counteracted the long-term effects induced by IMMO.

A5 region modulation of the cardiorespiratory responses evoked from parabrachial cell bodies in the anaesthetised rat.

We have examined the importance of the A5 region modulating cardiorespiratory responses evoked from the parabrachial complex (PB) in spontaneously breathing rats. Cardiorespiratory changes were analyzed in response to electrical stimulation and glutamate microinjections into the PB (10-20 nl, 1-2 nmol) before and after ipsilateral microinjection of muscimol (50 nl, 0.25 nmol) or lidocaine (50 nl, 0.5 nmol) within the A5 region. Stimulation of medial parabrachial and Kölliker-Fuse nuclei (mPB-KF) evoked a decrease in respiratory rate (P<0.001) with a rise in blood pressure (P<0.001) and heart rate (P<0.05). After muscimol or lidocaine microinjections within the A5 region, the pressor and heart rate responses to mPB-KF stimulation were reduced (P<0.05, both cases). Muscimol within the A5 region altered the respiratory response to glutamate stimulation of mPB-KF, evoking an increase in respiratory rate (P<0.05). Lidocaine abolished the respiratory response to mPB-KF stimulation. Stimulation of the lateral parabrachial nuclei (lPB) caused an increase in respiratory rate (P<0.001) with a rise in blood pressure (P<0.001) and heart rate (P<0.05). Muscimol or lidocaine microinjections within A5 region decreased heart rate (P<0.05) and pressor responses (P<0.05) evoked from lPB. The increase of respiratory rate persisted unchanged. To confirm functional interactions between A5 and PB, extracellular recordings of putative A5 neurones were obtained during PB stimulation. Eighty-three A5 cells were recorded, 35 were activated from the mPB-KF (42%). The results indicate that neurones of the A5 region participate in the cardiorespiratory response evoked from the different regions of the PB complex. The possible mechanisms involved in these interactions are discussed.

Immunohistochemical distribution of neuropeptides inthe amygdaloid complex of the cat. A comparative study in mammals / Distribución inmunohistoquímica de neuropéptidos en el complejo de la amígdala del gato. Estudio comparativo en mamíferos

The distribution of several neuropeptides in the amygdaloid complex of the cat is described. Five of the neuropeptides studied (luteinizing hormone-releasing hormone, ?-endorphin, dynorphin A (1-17), ?-melanocyte-stimulating hormone or galanin) did not show immunoreactive profiles, whereas neuropeptide Y and somatostatin displayed the widest distribution throughout the amygdaloid nuclei. The medial amygdala (medial nucleus, medial division of the central nucleus) contained the highest number of the neuropeptides studied, whereas the lateral nucleus displayed the lowest amount of immunoreactive profiles. In addition, the morphological data suggest the possible co-existence of several neuropeptides in the same fibers and/or cell bodies, and a comparison with previous studies on the projections of the amygdaloid nuclei in the cat allows us to speculate about the possible peptidergic content of these pathways. The distribution of the neuropeptides studied in the cat is compared with the location of the same peptides in the amygdaloid complex of other mammalian species. Finally, the possible physiological functions of the neuropeptides, as well as aspects of future research into the morphology of neuropeptides in the cat amygdala are discussed (AU)

En este trabajo se describe la distribución inmunohistoquímica de varios neuropéptidos en el complejo de la amígdala del gato. No se ha encontrado marcaje para cinco de los neuropéptidos estudiados: hormona liberadora de hormona luteinizante, ß-endorfina, dinorfina A (1-17), hormona estimulante de melanocitos (forma ?)? y galanina. Sin embargo, el neuropéptido Y y la somatostatina presentan la distribución más amplia de todos los péptidos estudiados en los núcleos de la amígdala del gato. Por regiones, la amígdala medial (núcleo medial y división medial del núcleo central) contiene el mayor número de neuropéptidos estudiados, mientras que la distribución más restringida se observa en el núcleo lateral de la amígdala. Además, los datos morfológicos obtenidos sugieren la posibilidad de que diferentes neuropéptidos coexistan en las mismas fibras y/o neuronas de algunos núcleos de la amígdala. Comparando los resultados obtenidos en este estudio con otros trabajos morfológicos sobre proyecciones de los núcleos de la amígdala se sugiere la posible naturaleza peptidérgica de dichas proyecciones. Además, se compara la distribución de los neuropéptidos estudiados en la amígdala del gato con los datos disponibles sobre la distribución de las mismas sustancias en la amígdala de otras especies animales de mamíferos. Por último, se discuten las posibles funciones fisiológicas de los neuropéptidos estudiados, así como las líneas de investigación que pueden llevarse a cabo sobre morfología de neuropéptidos en el complejo de la amígdala del gato en base a los resultados presentados en el presente trabajo (AU)

[Implication of the neuropeptides methionine enkephalin, neurotensin and somatostatin of the caudal trigeminal nucleus in the experimental migraine]. / Implicación de los neuropéptidos metionina-encefalina, neurotensina y somatostatina del núcleo caudal del trigémino en la migraña experimental.

INTRODUCTION: Primary peptidergic sensory neurons of the trigeminal ganglion that innervate the cerebral dura have been involved in the pathogenesis of headache, including the migraine. In addition, it is known that nociceptive central processes of the trigeminal neurons terminate in the caudal trigeminal nucleus. Moreover, the electrical stimulation of the trigeminal ganglion has been used as an experimental model in order to study the vascular headache, including the migraine. AIM: To study whether there is or not a decrease of the immunoreactivity for methionine enkephalin, somatostatin and neurotensin in the caudal trigeminal nucleus after electrical stimulation of the trigeminal ganglion. MATERIAL AND METHODS: The trigeminal ganglia of Wistar albino rats of both sexes were electrically stimulated (frequency, 5 Hz; duration, 5 ms; intensity, 0,8 1.4 mA) and unilaterally for five minutes. Sections of the medulla oblongata containing the caudal trigeminal nucleus were obtained and processed for immunocytochemistry, in which specific antibodies were used against methionine enkephalin, neurotensin and somatostatin 28. RESULTS: In stimulated animals, we observed a decrease in the immunoreactivity for the three neuropeptides studied in the stimulated (ipsilateral) side, in comparison with the not stimulated side (contralateral). In control animals (not stimulated) the degree of the immunoreactivity was the same on both sides. CONCLUSIONS: 1. The decrease of the immunoreactivity in the ipsilateral side (stimulated) suggests that methionine enkephalin, neurotensin and somatostatin 28 are released in the caudal trigeminal nucleus after electrical stimulation of the trigeminal ganglion; 2. Methionine enkephalin and somatostatin 28 could act in the caudal trigeminal nucleus as inhibitors (with antinociceptive action) of another released exciters neuropeptides (with nociceptive action); and 3. These data will allow in the future to try new therapeutic strategies (e.g., the inhibition of the receptors implicated.), in order to alleviate certain headaches.

Neuropeptides in the cat diencephalon: II. Hypothalamus

We have reviewed the distribution and functions of neuropeptides in the cat hypothalamus. Our review focuses in the cat hypothalamus on the following points: 1) the distribution and coexistence of neuropeptides; 2) the anatomical relationships among the different neuropeptides; 3) the peptidergic pathways (afferences and efferences); 4) comparison of the distribution of neuropeptides in the mammalian hypothalamus; and 5) the physiological functions of neuropeptides. Although at present the distribution of many neuropeptides in the hypothalamus of the cat is known, there is little information about other aspects of neuropeptides in the same diencephalic region. Thus, in order to know more the distribution and functions of neuropeptides in the cat hypothalamus in detail, in the future appropriate methodologies must be applied in order to determine, for example, the distribution of the neuropeptide receptors, the distribution of neuropeptidases, the peptidergic synaptic connections, the coexistence of neuropeptides and the physiological actions of the neuropeptides in the cat hypothalamus (AU)

Hemos revisado la distribución y las funciones de diferentes neuropéptidos en el hipotálamo del gato. Nuestra revisión se centra en los siguientes puntos: 1) la distribución y coexistencia de neuropéptidos; 2) las relaciones anatómicas entre los diversos neuropéptidos; 3) las vías peptidérgicas (aferencias y referencias); 4) la comparación de la distribución de neuropéptidos en el hipotálamo de mamíferos; y 5) las funciones fisiológicas de los neuropéptidos. Aunque actualmente la distribución de muchos neuropéptidos en el hipotálamo del gato es conocida, hay poca información sobre otros aspectos de estos neuropéptidos en la misma región diencefálica. Por eso, con el fin de conocer más detalladamente la distribución y las funciones de los neuropéptidos en el hipotálamo del gato, han de ser aplicadas en el futuro las metodologías adecuadas para determinar, por ejemplo, la distribución de los receptores de neuropéptidos, la distribución de neuropeptidasas, las conexiones sinápticas peptidérgicas, la coexistencia de neuropéptidos y las acciones fisiológicas de los neuropéptidos en el hipotálamo del gato (AU)

Laryngeal effects of stimulation of rostral and ventral pons in the anaesthetized rat.

In order to study the importance of two pontine regions modulating laryngeal resistance, electrical current or microinjections of glutamate (10-30 nl, 1-3 nmol) were made into the pontine parabrachial complex and the A5 region in spontaneously breathing anaesthetized rats. Two distinct patterns of laryngeal and respiratory responses were elicited. An increase of subglottal pressure was accompanied with an expiratory facilitatory response consisted of a decrease in both respiratory rate and phrenic nerve activity. A decrease of subglottal pressure was accompanied with an inspiratory facilitatory response consisted of an increase in both respiratory rate and phrenic nerve activity. The modification of laryngeal calibre occurred during both respiratory phases in most cases. The concomitant cardiovascular changes of these responses were also analyzed. Controls using guanethidine to block autonomic responses which might interact with respiratory control were also made. Histological analysis of stimulation sites showed a topographical organization of these responses: laryngeal constriction was evoked from Kölliker-Fuse, medial parabrachial nuclei and A5 region, whilst the laryngeal dilation was evoked from the lateral parabrachial nucleus.

Implicación de los neuropéptidos metionina-encefalina, neurotensina y somatostatina del núcleo caudal del trigémino en la migraña experimental / Implication of the neuropeptides methionine-enkephalin, neurotensin and somatostatin of the caudal trigeminal nucleus in the experimental migraine

Introducción. Las neuronas peptidérgicas sensoriales primarias del ganglio del trigémino que inervan la duramadre se han involucrado en la patogénesis de la cefalea, incluida la migraña. También se sabe que las terminaciones nociceptivas de las neuronas trigeminales finalizan en el núcleo caudal del trigémino, y que la estimulación eléctrica del ganglio del trigémino se ha utilizado como modelo experimental para estudiar la cefalea de origen vascular, incluyendo la migraña. Objetivo. Estudiar si hay disminución de la inmunorreactividad para la metionina-encefalina, somatostatina y neurotensina en el núcleo caudal del trigémino tras estimular eléctricamente el ganglio del trigémino. Material y métodos. El ganglio del trigémino de ratas Wistar albinas de ambos sexos se estimuló eléctricamente (frecuencia, 7,5 Hz; duración, 5 ms; intensidad, 0,8-1,4 mA) y unilateralmente durante cinco minutos. Una vez obtenidas las secciones del bulbo raquídeo que contienen el núcleo caudal del trigémino, se realizó una técnica inmunocitoquímica en la que se utilizaron anticuerpos específicos contra la metionina-encefalina, neurotensina y somatostatina-28. Resultados. En los animales que se estimularon observamos una disminución de la inmunorreactividad para los tres neuropéptidos en el lado estimulado (ipsilateral) con respecto al no estimulado (contralateral). En los animales controles (no estimulados), el grado de inmunorreactividad observado fue idéntico en ambos lados. Conclusiones. 1. La disminución de la inmunorreactividad en el lado ipsilateral (estimulado) indica que la metionina-encefalina, neurotensina y somatostatina-28 se liberan en el núcleo caudal del trigémino tras estimular eléctricamente el ganglio del trigémino; 2. La metionina-encefalina y la somatostatina-28 en el núcleo caudal del trigémino podrían actuar como inhibidores (con acción antinociceptiva) de otros neuropéptidos que se liberan y que tienen una acción excitadora (con acción nociceptiva); y 3. Estos datos permitirán ensayar nuevas estrategias terapéuticas en el futuro (ej., inhibición de los receptores implicados...) con la finalidad de tratar ciertas cefaleas (AU)

Neuropeptides in the cat diencephalon: I. Thalamus / Neuropeptidos en el diencéfalo del gato: i. Tálamo

In this paper we review the distribution and functions of neuropeptides in the cat thalamus. We focus our review on the following topics: 1) the distribution of neuropeptides in the cat thalamus; 2) the coexistence of neuropeptides in the cat thalamus; 3) the anatomical relationships between neuropeptides in the cat thalamus; 4) the peptidergic pathways in the cat thalamus; 5) a comparison of the distribution of neuropeptides in the mammalian thalamus; and 6) the physiological functions of neuropeptides in the cat thalamus. Although in recent years our knowledge of the distribution of neuropeptides in the cat thalamus has increased considerably, there still remains much to do in this feline brain region in order to know the distribution of other neuropeptides, the physiological interactions among them, the afferent and efferent peptidergic pathways, and the physiological roles of such neuropeptides. In the future, other methods (e.g., in situ hybridization, tract-tracing...) in addition to immunocytochemical methods should be used in the cat thalamus to increase our knowledge of the neuropeptides in this diencephalic region (AU)

En este artículo revisamos la distribución y funciones de los neuropéptidos en el tálamo del gato. Centramos nuestra revisión en los siguientes temas: 1) la distribución de neuropéptidos en el tálamo del gato; 2) la coexistencia de neuropéptidos en el tálamo del gato; 3) las relaciones anatómicas entre los neuropéptidos en el tálamo del gato; 4) las vías peptidérgicas en el tálamo del gato; 5) comparación de la distribución de los neuropéptidos en el tálamo de mamíferos; y 6) las funciones fisiológicas de los neuropéptidos en el tálamo del gato. Aunque en los últimos años nuestro conocimiento sobre la distribución de neuropéptidos en el tálamo del gato ha aumentado considerablemente, queda mucho por hacer todavía en esta región del cerebro felino para conocer la distribución de otros neuropéptidos, las interacciones fisiológicas entre ellos, las vías peptidérgicas aferentes y eferentes y los papeles fisiológicos de dichos neuropéptidos. En el futuro, otros métodos (por ejemplo, hibridación in situ, trazadores de tractos…) añadidos a métodos inmunocitoquímicos deberán ser usados en el tálamo del gato para aumentar nuestros conocimientos sobre los neuropéptidos en esta región diencefálica (AU)

[Neuropeptides in the raphe nuclei: an immunocytochemical study]. / Neuropéptidos en los núcleos del rafe: estudio inmunocitoquímico.

INTRODUCTION: The raphe nuclei are involved in numerous mechanisms, included the antinociceptives. In the raphe nuclei of the cat, the distribution of neuropeptides is not very studied. Aim. To know the distribution of peptidergic fibers and cell bodies in the raphe nuclei of the cat. We studied a total of fifteen neuropeptides. MATERIAL AND METHODS: We used four control cats (without colchicine) and six with colchicine (administered into the Sylvian aqueduct). We used an indirect immunocytochemical technique. The histologic controls carried out confirm the specificity of the primary and secondary antibodies used. RESULTS: We observed in the fibers and/or the cell bodies located in the dorsal raphe nucleus a total of 14 neuropeptides, 12 in the raphe pallidus, 11 in the medial raphe, 10 in the raphe magnus, 8 in the raphe pontis and 7 in the raphe obscurus. We observed immunoreactive cell bodies in the raphe pallidus (with neurokinin A/leucine enkephalin), in the medial raphe (beta endorphin/alpha neo endorphin), in the raphe magnus (leucine enkephalin) and in the dorsal raphe (beta endorphin/alpha neo endorphin/methionine enkephalin Arg6 Gly7 Leu8/leucine enkephalin/neurokinin A/neurotensin). CONCLUSIONS: 1. There are differences on the distribution of the peptidergic fibers/cell bodies observed in the raphe nuclei of the rat, the cat and the man; 2. The raphe nuclei could receive peptidergic afferences containing dynorphin A, galanin, neuropeptide Y, somatostatin ; 3. The cell bodies located in the medial raphe and containing beta endorphin or alpha neo endorphin could be projecting neurons; 4. There is a great functional complexity in the raphe nuclei due to the great number of neuropeptides observed in them; 5. The neuropeptides could interact between them, and 6. The neuropeptides located in the raphe nuclei could be involved in the control of the nociceptive information.

Group I mGluR antagonist AIDA protects nigral DA cells from MPTP-induced injury.

The effects of i.c.v. injection of AIDA, a group I mGluR antagonist, were studied on the nigral DA cells after MPTP-induced injury in the black mouse, using TH immunocytochemistry and unbiased stereology. MPTP reduced the total number of TH-IR neurons by 55.2% and non-TH-IR neurons by 27.5%. A 15 min AIDA pre-treatment (10 nmol) selectively counteracted the loss of TH-IR cells caused by MPTP as evaluated 10 days after the insult without changing the total number of non-neuronal cell nuclei. The results suggest that group I mGluR antagonists may have a neuroprotective role against MPTP-induced degeneration of DA neurons and thus probably also against neurodegenerative processes occurring in Parkinson's disease.

Central galanin and N-terminal galanin fragment induce c-Fos immunoreactivity in the medulla oblongata of the anesthetized rat.

This immunohistochemical study analyzed the c-Fos expression (c-Fos-ir) induced by galanin injections. Galanin and N-terminal galanin fragment (1-15) induced a significant increase of c-Fos expression (c-ir) within the medulla oblongata 90 min and 6 h. after intracisternal injections. This expression has been studied mainly in the nucleus of the solitary tract and in the ventrolateral medulla showing different temporal profiles for both peptides. The presence of c-Fos-ir in TH-positive cells was analyzed in all the groups. These results may be relevant to understand the role of galanin in several functions including central cardiovascular control.

Neuropéptidos en los núcleos del rafe: estudio inmunocitoquímico / Neuropeptides in the raphe nuclei: an immunocytochemical study

Introducción. Los núcleos del rafe están involucrados en numerosos mecanismos, incluidos los antinociceptivos. En el gato la distribución de los neuropéptidos en los núcleos del rafe está poco estudiada. Objetivo. Conocer la distribución de las fibras y somas peptidérgicos en los núcleos del rafe del gato. Estudiamos un total de 15 neuropéptidos. Material y métodos. Utilizamos cuatro gatos controles (sin colchicina) y seis con colchicina (administrada en el acueducto de Silvio). Hemos empleado una técnica inmunocitoquímica indirecta. Los controles histológicos realizados confirmaron la especificidad de los anticuerpos primarios y secundarios utilizados. Resultados. Hemos observado en las fibras y somas localizados en el núcleo dorsal del rafe un total de 14 neuropéptidos, 12 en el rafe pálido, 11en el rafe medial, 10 en el rafe magno, 8 en el rafe pontis y 7 en el rafe oscuro. Observamos somas inmunorreactivos en el rafe pálido (con neuroquinina A/leucina-encefalina), en el rafe medial (beta-endorfina/alfa-neo-endorfina), en el rafe magno (leucina-encefalina) y en el dorsal del rafe (betaendorfina/alfaneoendorfina/ metionina-encefalina-Arg6-Gly7-Leu8/leucina-encefalina/neuroquinina A/neurotensina). Conclusiones. 1. Existen diferencias en la distribución de las fibras/somas peptidérgicos observados en los núcleos del rafe de la rata, del gato y del hombre; 2. Los núcleos del rafe podrían recibir aferencias peptidérgicas con dinorfina A, galanina, neuropéptido Y, somatostatina...; 3. Los somas con betaendorfina o con alfa-neo-endorfina localizados en el rafe medial podrían ser neuronas de proyección; 4. Existe una gran complejidad funcional en los núcleos del rafe debido al gran número de neuropéptidos observados; 5. Los neuropéptidos podrían interactuar entre sí, y 6. Los neuropéptidos localizados en los núcleos del rafe podrían intervenir en el control de la información nociceptiva (AU)

Respiratory effects of stimulation of cell bodies of the A5 region in the anaesthetised rat.

To assess the importance of the pontine A5 region in modulating respiratory activity, electric current or microinjections of glutamate (10-30 nl, 1-3 nmol) were used to stimulate discrete zones within this region in the spontaneously breathing, anaesthetised rat. These stimuli evoked an expiratory facilitatory response, consisting of a decrease in respiratory rate (P < 0.01 electrical, P < 0.001 chemical) due to an increase of expiratory time (P < 0.01 in both cases) as measured from recordings of phrenic nerve activity. No changes were observed in inspiratory time. To avoid changes in PCO2, which could modulate the respiratory response, stimulation was also made during artificial ventilation. Under these conditions the expiratory facilitatory response elicited by glutamate was still present (P < 0.05), although its duration was reduced (P < 0.05), as was the magnitude of the phrenic burst (P < 0.05). At all the sites at which electrical stimulation and glutamate injection had evoked a respiratory response, electrical stimulation evoked a concomitant increase in both blood pressure and heart rate. Glutamate injection evoked a pressor response in 21 out of 30 animals. In eight animals the rise in blood pressure was followed by a fall in blood pressure and in one animal, a depressor response was observed. In all cases glutamate evoked an increase in heart rate. The expiratory facilitatory response was not evoked as a consequence of the increase of blood pressure since it was still present after the administration of guanethidine, which abolished the blood pressure changes. As glutamate is believed to excite perikarya rather than axons of passage these data indicate that expiratory facilitatory responses and the accompanying cardiovascular changes are the consequence of activating neurones located within the A5 region. The possible interactions between the A5 region and the medullary respiratory complex in eliciting these changes are discussed.