RESUMEN
OBJECTIVE: Most cancer patients desire information about care options at the end of life, including cardiopulmonary resuscitation (CPR). Communicating such care options can be challenging and is part of advance care planning (ACP). Our prior studies with video educational media produced data on patients' categoric preferences (yes/no/unsure) for CPR; however, the thematic underpinnings of these educated preferences in patients treated for advanced cancer aren't well known. METHODS: Qualitative thematic content analysis of participants' responses in a randomized trial of an educational video (V) or narrative (N) about CPR in patients with advanced gastrointestinal cancers. Responses were independently coded and categorized for thematic content by two reviewers. RESULTS: Of 54 study participants, 26 total (41% of V arm, 56% of N arm) articulated questions, comments, or both. Reviewer analyses demonstrated thematic consensus and resulted in seven distinct themes listed in decreasing order of prevalence: (a) ACP should be started early; (b) educational information about CPR affirmed participants' existing beliefs/knowledge/values about advanced illness; (c) participants were apprehensive about ACP but wanted to discuss it; (d) gaps in knowledge about ACP emerged; (e) CPR information was helpful/acceptable; (f) physicians should be involved in ACP; and (g) medical questions about critical illness arose. CONCLUSIONS: Findings identified that while sometimes difficult to discuss, advance care planning is desired, deemed helpful, and ideally begun early by clinicians, and that video education is an appropriate and affirming initiator of discussions. These themes are incorporated into our ongoing research on cancer patient-specific values and education about care options.
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Planificación Anticipada de Atención , Reanimación Cardiopulmonar/psicología , Neoplasias/terapia , Educación del Paciente como Asunto , Participación del Paciente/psicología , Prioridad del Paciente/psicología , Adulto , Anciano , Actitud Frente a la Salud , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Mirtazapine, a clinically effective antidepressant, acts by antagonizing central alpha2-adrenergic and 5-HT2/5-HT3 receptors. No data are available regarding mirtazapine's effects on sleep architecture in patients with major depressive disorder. METHODS: Six patients meeting criteria for major depressive disorder and scoring > or =4 on the three Hamilton Depression Rating Scale sleep items were studied. Polysomnographic evaluations were performed at baseline and after 1 (15 mg at bedtime) and 2 weeks (30 mg at bedtime) of open-label mirtazapine treatment. RESULTS: Mirtazapine significantly decreased sleep latency and significantly increased total sleep time and sleep efficiency from baseline levels during week 1, with similar results observed after week 2. Mirtazapine did not significantly alter rapid eye movement sleep parameters. Clinically, Hamilton Depression Rating Scale and sleep disturbance ratings improved after treatment. CONCLUSIONS: Mirtazapine significantly improves sleep continuity in major depressive disorder patients with poor sleep quality at weeks 1 and 2 of treatment, while preserving sleep architecture.
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Antagonistas Adrenérgicos alfa/farmacología , Antidepresivos Tricíclicos/farmacología , Trastorno Depresivo Mayor/tratamiento farmacológico , Mianserina/análogos & derivados , Trastornos del Inicio y del Mantenimiento del Sueño/tratamiento farmacológico , Fases del Sueño/efectos de los fármacos , Adolescente , Antagonistas Adrenérgicos alfa/uso terapéutico , Adulto , Anciano , Antidepresivos Tricíclicos/uso terapéutico , Trastorno Depresivo Mayor/fisiopatología , Femenino , Humanos , Masculino , Mianserina/farmacología , Mianserina/uso terapéutico , Persona de Mediana Edad , Mirtazapina , Proyectos Piloto , Polisomnografía , Escalas de Valoración Psiquiátrica , Trastornos del Inicio y del Mantenimiento del Sueño/fisiopatología , Resultado del TratamientoRESUMEN
BACKGROUND: It has been proposed that elevated central thyrotropin-releasing hormone (TRH) is associated with the blunted thyroid-stimulating hormone (TSH) response to TRH in patients with depression. Few studies have directly evaluated this relationship between central nervous system and peripheral endocrine systems in the same patient population. METHODS: 15 depressed patients (4 male, 11 female, 12 bipolar, and 3 unipolar) during a double-blind, medication-free period of at least 2 weeks duration, underwent a baseline lumbar puncture followed by a TRH stimulation test. Cerebrospinal fluid (CSF) TRH and serial serum TSH, free thyroxine, triiodothyronine, prolactin, and cortisol were measured. A blunted response to TRH was defined as a delta TSH less than 7 microU/mL. RESULTS: There was no significant difference in mean CSF TRH between "blunters" (2.82 +/- 1.36 pg/mL) and "non-blunters" (3.97 +/- 0.62 pg/mL, p = .40). There was no evidence of an inverse relationship between CSF TRH and baseline or delta TSH. There was no correlation between CSF TRH and the severity of depression or any other endocrine measure. CONCLUSIONS: These data are not consistent with the prediction of hypothalamic TRH hypersecretion and subsequent pituitary down-regulation in depression; however, CSF TRH may be from a nonparaventricular nucleus-hypothalamic source (i.e., limbic area, suprachiasmatic nucleus, brain stem-dorsal raphe) and thus, not necessarily related to peripheral neuroendocrine indices.
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Trastorno Bipolar/líquido cefalorraquídeo , Trastorno Depresivo/líquido cefalorraquídeo , Hormona Liberadora de Tirotropina/líquido cefalorraquídeo , Hormona Liberadora de Tirotropina/farmacología , Tirotropina/líquido cefalorraquídeo , Tirotropina/metabolismo , Adulto , Método Doble Ciego , Femenino , Humanos , Hidrocortisona/líquido cefalorraquídeo , Masculino , Prolactina/líquido cefalorraquídeo , Tiroxina/líquido cefalorraquídeo , Triyodotironina/líquido cefalorraquídeoRESUMEN
The design and synthesis of peptide mimetics of thyrotropin-releasing hormone (TRH) in which the peptide backbone is entirely replaced by a cyclohexane framework are described. The cis-1,3,5-trisubstituted ring was expected to permit key pharmacophoric groups to adopt conformations consistent with proposed bioactive conformations of the peptide. Compounds were synthesized by a stereoselective synthesis starting from L-glutamic acid. In a behavioral model of cognition in which TRH is active, the mimetics are potent, active compounds, exhibiting oral activity. One analog (26, (1S,3R,5(2S),5S)-5-[[5-oxo-1-(phenylmethyl)-2-pyrrolidinyl]-methyl]-5- [(1H-imidazol-5-yl)methyl]cyclohexaneacetamide) was radiolabeled for binding studies and evaluated in other binding assays and pharmacological tests. Competition binding of 26 vs [3H]MeTRH to rat brain slices suggests a two-site model for ligand binding with IC50's of 1 microM and 3 mM. Direct binding of [3H]-26 shows a biphasic curve with IC50's of 80 and 49 microM, respectively. Further studies would be needed to establish a link between the novel binding site(s) and the behavioral activity of 26 and TRH analogs.
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Trastornos del Conocimiento/tratamiento farmacológico , Cognición/efectos de los fármacos , Ciclohexanos/farmacología , Péptidos/síntesis química , Péptidos/farmacología , Hormona Liberadora de Tirotropina/fisiología , Secuencia de Aminoácidos , Animales , Ciclohexanos/síntesis química , Diseño de Fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Conformación Proteica , Ratas , Relación Estructura-Actividad , Hormona Liberadora de Tirotropina/análogos & derivadosRESUMEN
The role of thyrotropin-releasing hormone (TRH) in regulating circadian rhythms was investigated by assessing the ability of TRH microinjections into the suprachiasmatic nucleus (SCN) to induce phase shifts in hamster wheel-running behavior. TRH injected into the SCN at 10 and 100 nM doses produced phase advances in wheel-running activity of 18.3 +/- 1.9 and 34.8 +/- 2.9 minutes, respectively, when administered at circadian time (CT) 6. Injections at CT 18 produced no effects. The temporal sensitivity of the SCN to TRH administration was examined by administering TRH at specific circadian times. TRH produced significant phase advances at CT 4, 6, and 8, while no significant changes in wheel-running onset were observed at other CT times. These studies represent the first evidence of TRH's ability to affect circadian function.
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Ritmo Circadiano/fisiología , Núcleo Supraquiasmático/efectos de los fármacos , Hormona Liberadora de Tirotropina/farmacología , Animales , Cricetinae , MasculinoRESUMEN
Previous work found that dietary l-arginine alters symptom progression in mice transgenic for Huntington's disease (HD), and that cerebral blood flow (CBF) is abnormal in early stage HD patients. Both of these findings potentially implicate nitric oxide (NO) and its converting enzyme, nitric oxide synthase (NOS), in HD. The current experiment found that both NOS enzymatic activity and neuronal NOS (nNOS) protein expression were reduced (P<0.05) in R6/2 HD transgenic mice compared to non-HD controls (CON). Conversely, inducible NOS (iNOS) protein expression was not significantly different between groups. The changes in nNOS were accompanied by changes in protein expression of calmodulin kinase II (CaMKII) (P<0.05) and calmodulin kinase IV (CaMKIV) (P<0.05). Protein expression of 3-nitrotyrosine (3-NT), a marker for the neurotoxin peroxynitrite, was slightly increased in non-drug treated HD and was accompanied by increased immunostaining of 3-NT in cells adhering to the vasculature and choroid plexus. Mice that received the broad-spectrum NOS inhibitor N(g)-nitro-L-arginine methyl ester hydrochloride (L-NAME) via their drinking water had reduced NOS enzyme activity. NOS activity varied as a function of L-NAME dose, was virtually eliminated in the 500-mg/l groups, and correlated (P<0.05) with the behavioral scores as revealed by regression and correlation analyses. High dose L-NAME (500 mg/l) accelerated symptom onset in HD transgenics. These results support the hypothesis that nNOS activity and NO production are abnormal in HD, this in the setting of a more global dysregulation of calcium protein expression. Taken collectively with earlier data from our laboratory demonstrating abnormal CBF findings in early-stage HD patients, these results suggest that abnormalities in NOS function may significantly contribute to the neurodegeneration found in HD.
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Inhibidores Enzimáticos/farmacología , Enfermedad de Huntington/enzimología , Enfermedad de Huntington/genética , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico Sintasa/metabolismo , Tirosina/análogos & derivados , Animales , Conducta Animal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/enzimología , Proteínas Quinasas Dependientes de Calcio-Calmodulina/biosíntesis , Modelos Animales de Enfermedad , Femenino , Enfermedad de Huntington/fisiopatología , Inmunohistoquímica , Masculino , Ratones , Ratones Transgénicos , Actividad Motora/efectos de los fármacos , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/biosíntesis , Óxido Nítrico Sintasa de Tipo I , Tirosina/biosíntesisRESUMEN
Recent neuroimaging studies reported complex changes in cerebral blood flow (CBF) in early-staged Huntington's disease (HD) patients. Deckel and co-workers [Deckel and Duffy, Brain Res. (in press); Deckel and Cohen, Prog. Neuro-Psychopharmacol. Biol. Psychiatry 24 (2000) 193; Deckel et al., Neurology 51 (1998) 1576; Deckel et al., J. Nucl. Med. 41 (2000) 773] suggested that these findings might be accounted for, in part, by alterations in cerebral nitric oxide (NO) and its byproduct, peroxynitrite. The current experiment tested this hypothesis by altering NO levels via manipulations of dietary L-arginine (ARG), the dietary precursor of NO, in mice transgenic for HD. Seventy-one mice were assigned at 12 weeks of age to one of three isocaloric diets that varied in their content of ARG. These diets included: (a) 0% ARG, (b) 1.2% ARG (i.e. typical mouse chow), or (c) 5% ARG. The 5% ARG diets in HD mice accelerated the time of onset of body weight loss (P<0.05) and motor impairments (P<0.05), and increased resting CBF in HD relative to control (P<0.05). Conversely, the 0% ARG diet demonstrated no loss of body weight and had no changes in CBF relative to controls. However, the 0% ARG HD group continued to show significant deficits on motor testing (P<0. 05). The 1.2% ARG HD group showed reduced body weight loss, better motor functioning, and fewer changes in CBF compared to the 5% ARG HD group. Immunocytochemistry analysis found greater deposition of nitrotyrosine in the cortex, and vasculature, of HD+ mice, 5% and 1. 2%>0% arginine diets. When collapsed across all conditions, CBF inversely correlated (P<0.05) both with the body weight and motor changes suggesting that changes in CBF are associated with behavioral decline in HD mice. Collectively, these findings indicate that dietary consumption of the NO precursor ARG has a measurable, but complex, effect on symptom progression in HD transgenic mice, and implicates NO in the pathophysiology of HD.
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Arginina/administración & dosificación , Enfermedad de Huntington/fisiopatología , Tirosina/análogos & derivados , Animales , Arginina/farmacología , Glucemia/análisis , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Circulación Cerebrovascular/efectos de los fármacos , Dieta , Enfermedad de Huntington/complicaciones , Enfermedad de Huntington/genética , Enfermedad de Huntington/patología , Ratones , Ratones Transgénicos/genética , Trastornos del Movimiento/etiología , Factores de Tiempo , Tirosina/metabolismo , Pérdida de PesoRESUMEN
The onset of dopaminergic innervation and its effects on melanotrope proliferation were investigated in the rat pituitary intermediate lobe. Dopamine, and its synthetic rate-limiting enzyme tyrosine hydroxylase, were first detected immunohistochemically on late post-natal day 3 or early postnatal day 4. Axon density was highest at the neural lobe/intermediate lobe border, and decreased toward the pituitary cleft. By postnatal day 10, the adult pattern of tyrosine hydroxylase immunoreactivity was established and remained through post-natal day 14. Neurointermediate lobe dopamine levels, measured by HPLC, correlated well with the increased axon density observed in the immunohistochemical studies. Dopamine could not be measured by our assay (100 fg limit) until post-natal day 3 (439.32 fg/NIL). Dopamine concentration increased to 2.09 +/- 0.425 ng at PN 4, 86.31 +/- 20.42 ng at PN 7, 168.72 +/- 18.37 ng at PN 10. Melanotrope proliferation was determined by [3H]thymidine incorporation before and after innervation. Concomitant with the onset of innervation, the proliferation index dropped from 13.4 +/- 0.01% to 6.5 +/- 0.002% at PN 4, and continued to decrease until a level of 3 +/- 0.003% was established by PN 10. To confirm the inhibitory action of dopaminergic innervation on melanotrope proliferation, rat neonates were injected intracisternally with 150 mg 6-hydroxydopamine to destroy dopaminergic axons within the intermediate lobe. Measurement of dopamine concentrations in neurointermediate lobes of injected animals showed a decrease in dopamine levels as compared to controls. From PN 4 (0.88 +/- 0.165 ng), DA levels gradually increased during development: at PN 5, [DA] = 0.689 +/- 0.104 ng; PN 6 [DA] = 11.60 +/- 2.24 ng; PN 7 [DA] = 20.93 +/- 3.80 ng; and PN 10 [DA] = 27.95 +/- 3.46 ng. Melanotrope proliferation also increased in 6-hydroxydopamine-treated animals. At PN 4, the onset of innervation reduced the pre-innervation proliferation index to 8.75 +/- 0.002%, only a 30% reduction in contrast to the greater than 50% decrease observed in control animals. A stable proliferation level of approximately 7.5% persisted in all subsequent stages with 6-OHDA administration. Our results demonstrated the time of dopamine innervation onset and a characteristic developmental pattern for axons within the rat intermediate lobe. The onset of innervation and increased dopamine concentration suggests increased dopaminergic control of the melanotropes, illustrated specifically by a decrease in their level of proliferation. This is the first presentation of evidence showing that dopaminergic innervation within the intermediate lobe of the rat pituitary regulates melanotrope proliferation.
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Dopamina/fisiología , Hipófisis/crecimiento & desarrollo , Animales , División Celular/fisiología , Cromatografía Líquida de Alta Presión , Dopamina/análisis , Dopamina/metabolismo , Femenino , Inmunohistoquímica , Oxidopamina/farmacología , Hipófisis/citología , Hipófisis/fisiología , Embarazo , Ratas , Ratas Endogámicas , Timidina/metabolismo , Tirosina 3-Monooxigenasa/inmunología , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
This study demonstrated morphological changes in glial-like cells of the rat pituitary intermediate lobe during early postnatal development, and a subsequent shift in protein expression from vimentin to GFAP. Vimentin immunoreactivity was detected in the lobe at embryo day 14 and was localized in radially-oriented, bipolar cells whose processes spanned the thickness of the intermediate lobe. At electron microscopical resolution, processes contained intermediate filaments, cell nuclei were indented while secretory vesicles characteristic of the endocrine cells were not found. Vimentin immunoreactive intensity began to decrease at postnatal day 5. By postnatal day 7, vimentin-positive, stellate cells were observed, with few radial processes found by day 10. The intensity of vimentin immunoreactivity decreased through day 25. Within the lobe parenchyma, vimentin was localized in glial-like cells since double-label immunohistochemistry revealed no colocalization of beta-endorphin and vimentin, or fibronectin and vimentin. Dopamine-containing axons were in close apposition to vimentin-positive processes. GFAP immunoreactivity first appeared on postnatal day 20 and, by day 25, stellate cell bodies with three to six extended processes were evident. Cells were primarily distributed in the caudal third of the lobe. The characteristic adult pattern of cell clusters in latero-dorsal and ventral portions of the lobe was fully established by postnatal day 55. The transition from vimentin to GFAP expression and concurrent morphological changes resemble those described for radial glial during cerebral cortical development.
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Proteína Ácida Fibrilar de la Glía/biosíntesis , Neuroglía/ultraestructura , Hipófisis/metabolismo , Vimentina/biosíntesis , Animales , Animales Recién Nacidos , Axones/fisiología , Polaridad Celular , Tamaño de la Célula , Desarrollo Embrionario y Fetal/fisiología , Femenino , Fibronectinas/análisis , Técnica del Anticuerpo Fluorescente , Proteína Ácida Fibrilar de la Glía/análisis , Masculino , Neuroglía/metabolismo , Hipófisis/anatomía & histología , Hipófisis/crecimiento & desarrollo , Ratas , Ratas Sprague-Dawley , Tirosina 3-Monooxigenasa/análisis , Vimentina/análisis , betaendorfina/análisisRESUMEN
S-100, an acidic calcium-binding protein, is co-localized with vimentin in glial-like cells in the adult rat pituitary intermediate lobe. S-100 and melanotrope markers were not co-localized in the adult. During development, S-100 and vimentin were not co-localized but appeared in cells with different morphological characteristics. S-100 was co-localized with POMC mRNA and beta-endorphin during prenatal time and the first three postnatal weeks. This was demonstrated by double-label immunohistochemistry, using combinations of antisera against S-100, vimentin and beta-endorphin, and in situ hybridization histochemistry for POMC mRNA combined with immunohistochemistry for S-100. In the second and third weeks of postnatal development, S-100 was observed in fewer melanotropes and more frequently in stellate cells, which also expressed vimentin. Thus, S-100 appeared to be transiently expressed in melanotropes during prenatal and early postnatal development. S-100 serves as a neurotrophic and glial maturation factor in the CNS. Since S-100 expression in melanotropes coincides with the onset of dopaminergic innervation and morphological changes in glial-like cells of the lobe, it could have similar functions in the rat pituitary intermediate lobe.
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Melanóforos/metabolismo , Neuroglía/metabolismo , Hipófisis/metabolismo , Proteínas S100/biosíntesis , Animales , Animales Recién Nacidos , Secuencia de Bases , Tejido Conectivo/metabolismo , Células del Tejido Conectivo , Desarrollo Embrionario y Fetal/fisiología , Edad Gestacional , Inmunohistoquímica , Melanóforos/citología , Datos de Secuencia Molecular , Hipófisis/embriología , Hipófisis/crecimiento & desarrollo , Ratas , Ratas Sprague-Dawley , Proteínas S100/análisis , Factores de TiempoRESUMEN
This study measured melanotrope mRNA and protein expression for the dopamine D2 receptor, and its long isoform, in relation to the appearance of dopamine in axons of the postnatal rat pituitary intermediate lobe. At postnatal day 2, prior to the onset of dopaminergic innervation, D2 receptor (D2T) mRNA was expressed heterogeneously in a subpopulation of melanotropes which also expressed the long isoform (DL). The D2L mRNA appeared to be predominant during early postnatal development, since the D2T probe, which did not discriminate between the isoforms, and the D2L probe hybridized generally to the same cells, as demonstrated in serial sections. Immunohistochemical methods, using two different antisera for the D2T receptor, however, indicated a low level of protein in most melanotropes. Localization of D2L protein corresponded well to D2T receptor mRNA distribution. At day 10, representing a time when dopamine is present in axons throughout the lobe, both D2T receptor mRNA and protein were detected in a significantly larger population of melanotropes than those expressing D2L mRNA and protein. This suggests the appearance of detectable short isoform (D2S) mRNA in virtually all melanotropes and implicates dopamine as a possible signal for increasing D2S isoform mRNA expression.
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Hipófisis/crecimiento & desarrollo , Hipófisis/metabolismo , Receptores de Dopamina D2/biosíntesis , Animales , Secuencia de Bases , Femenino , Inmunohistoquímica , Hibridación in Situ , Isomerismo , Microscopía Fluorescente , Datos de Secuencia Molecular , Hipófisis/citología , Embarazo , ARN Mensajero/biosíntesis , Ratas , Ratas Sprague-Dawley , Vimentina/metabolismo , betaendorfina/metabolismoRESUMEN
BACKGROUND: Circadian and sleep components modulate anterior pituitary release of thyrotropin (TSH), the chemical substance regulating the thyroid hormones, thyroxine (T4), and triiodothyronine (T3). The present study examined TSH, T4, and T3 concentrations across the wake-sleep boundary time (2300-0130 hours) before, during, and after a 64-h sleep deprivation paradigm. Additionally, adrenocorticotropic hormone (ACTH) and cortisol were measured as an index of hypothalamic-pituitary-adrenal axis activation. Activity levels and ratings of effort required to perform cognitive tasks were also incorporated to evaluate physical and cognitive load, respectively, across the study period. Assessing the combined effects of activity and sleep deprivation on thyroid hormone economy is relevant to the relationship of high physical and/or cognitive performance demands during sleep deprivation inherent in extended military operations and space exploration. METHODS: There were 12 healthy subjects who were monitored during a 2-d baseline period, 3 d of total sleep deprivation, and 2 nights of recovery sleep. Serum samples were collected at 2300 hours and 0130 hours across the entire study period, and measured for TSH, T4, T3, and glucocorticoids. RESULTS: Change scores evaluated at the wake-sleep boundary time demonstrated significant inhibitory effects of sleep on thyroid hormone measures. As expected, sleep deprivation was associated with elevated TSH. However, sleep deprivation also significantly increased circulating levels of T3 at 2300 hours and T4 concentration change scores (2300-0130 hours). Glucocorticoid levels did not track thyroid hormone changes. Physical activity remained constant while subjective ratings of effort to perform cognitive tasks increased significantly during sleep deprivation. CONCLUSION: Compared to sleep deprivation studies under constant conditions reporting no change in peripheral T4 and T3 levels, the present study suggests activity level, including cognitive effort to perform, during total sleep deprivation may produce substantive changes in the thyroid axis.
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Sistema Hipotálamo-Hipofisario/fisiología , Privación de Sueño/fisiología , Glándula Tiroides/fisiología , Hormonas Tiroideas/sangre , Adulto , Femenino , Humanos , Masculino , Tirotropina/sangre , Tiroxina/sangre , Triyodotironina/sangre , Vigilia/fisiologíaAsunto(s)
Expresión Génica , Hormonas Estimuladoras de los Melanocitos/biosíntesis , Hipófisis/metabolismo , Proopiomelanocortina/biosíntesis , ARN Mensajero/metabolismo , Receptores de Dopamina D2/biosíntesis , Animales , Técnica del Anticuerpo Fluorescente , Hipófisis/citología , Adenohipófisis/metabolismo , Neurohipófisis/metabolismo , Ratas , Receptores de Dopamina D2/análisisRESUMEN
Glial-like cells in rat pituitary intermediate lobe were localized and characterized by immunohistochemistry with antisera against glial fibrillary acidic protein (GFAP) and S-100. Individual GFAP immunoreactive (IR) cells possessed several processes that often branched into secondary and tertiary processes, terminating with end-feet. The GFAP-immunopositive cell population was distributed in specific rostrocaudal and dorsoventral patterns. The distribution and numbers of cells differed between male and female rats. Examination of altered physiological states, e.g., adrenalectomy, lactation, and salt-loading, revealed state-specific changes in the appearance and distribution of GFAP-IR cells. Adrenalectomy and lactation increased GFAP-IR glial-like cell numbers, whereas salt-loading decreased their numbers and the typical pattern of distribution. By contrast, S-100-expressing cells were evenly distributed in male and female rats, and its expression was not affected by the experimental conditions. Double-label immunocytochemistry indicated that GFAP-IR cells are a subpopulation of S-100-IR cells. These results suggest that cells normally expressing only S-100 may be induced to express GFAP under altered physiologic conditions.
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Proteína Ácida Fibrilar de la Glía/genética , Neuroglía/fisiología , Hipófisis/fisiología , Adrenalectomía , Animales , Femenino , Expresión Génica , Inmunohistoquímica , Lactancia , Masculino , Ratas , Ratas Sprague-Dawley , Cloruro de Sodio Dietético/administración & dosificaciónRESUMEN
This review summarizes current findings regarding effects of antidepressant compounds on sleep architecture and interprets their clinical relevance. Effects of the major classes of antidepressant drugs on sleep properties are presented, with the antidepressant compounds organized into categories based primarily on their putative mechanism of action. The majority of antidepressant compounds, across several different categories, exhibit robust suppression of REM sleep. Others, such as bupropion and nefazodone, lack REM suppressant effects. Such findings support the idea that critical neurochemical mechanisms involved in the regulation of discrete sleep stages can be elucidated by means of polysomnographic investigations utilizing pharmacologically targeted agents. Clinicians have appreciated the importance of antidepressant drug effects on sleep when considering therapeutic options for patients. While such decisions in the past were based on empirical observations, an increasing amount of information regarding specific effects of different antidepressant drugs on sleep continuity and sleep architecture is available. Thus, clinicians may choose to consider profiles of sleep effects for different antidepressant drugs in the initial selection of an antidepressant compound.
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Antidepresivos/uso terapéutico , Trastorno Depresivo/tratamiento farmacológico , Trastorno Depresivo/fisiopatología , Sueño/efectos de los fármacos , Sueño/fisiología , Humanos , PolisomnografíaRESUMEN
Dopamine and GABA were detected in intermediate lobe axons around birth, and early axons were closely apposed to glial cells and processes, possibly using them for guidance. In the adult, axons containing colocalized dopamine and GABA were distributed in a distinct pattern within the lobe, with plexuses located dorsally and ventrally. Axons preferentially followed glial processes in interlobular septa, yet were also interspersed between melanotropes. Individual melanotropes were contacted by varying numbers of axon terminals, with some devoid of contacts. Boutons contained both small clear vesicles and large dense-cored vesicles; membrane specializations were not well-developed. From these findings we concluded that in addition to direct synaptic inhibition, dopamine and GABA could stimulate their receptors by mechanisms similar to "parasynaptic" [Schmitt (1984) Neuroscience, 13:991-1001] or "volume" [Agnati et al. (1995) Neuroscience, 69:711-726] transmission as proposed for the CNS. Humoral agents passing into the intermediate lobe from portal vessels, thus acting as classical hormones, further regulate the melanotropes. Moreover, approximately 50% of the axonal elements were closely apposed to glia, suggesting that glia could have regulatory roles. Previous studies from our laboratory [Chronwall et al. (1987) Endocrinology, 120:1201-1211; Chronwall et al. (1988) Endocrinology, 123:1992:1202] demonstrated heterogeneity in proopiomelanocortin (POMC) biosynthesis among individual melanotropes, prompting the hypothesis that the degree of innervation could govern the expression of certain molecules. We combined immunohistochemistry and in situ hybridization histochemistry to evaluate whether melanotrope molecular heterogenity is spatially correlated with axons and terminals. Tentatively, melanotropes expressing low levels of POMC and alpha1A subunit P/Q type Ca2+ channel mRNAs often were apposed to axons, whereas those with low levels of D2L receptor mRNA rarely were contacted by axons, suggesting that innervation could be one of the factors inducing and maintaining heterogeneity.
Asunto(s)
Melanóforos/fisiología , Hipófisis/embriología , Hipófisis/inervación , Factores de Edad , Animales , Axones/química , Axones/enzimología , Axones/ultraestructura , Canales de Calcio/genética , Dopamina/fisiología , Femenino , Proteína Ácida Fibrilar de la Glía/análisis , Glutamato Descarboxilasa/análisis , Masculino , Microscopía Electrónica , Sistema Nervioso Parasimpático/embriología , Sistema Nervioso Parasimpático/enzimología , Sistema Nervioso Parasimpático/ultraestructura , Hipófisis/ultraestructura , Embarazo , ARN Mensajero/análisis , Ratas , Ratas Sprague-Dawley , Sinapsis/química , Sinapsis/fisiología , Sinapsis/ultraestructura , Tirosina 3-Monooxigenasa/análisis , Ácido gamma-Aminobutírico/análisis , Ácido gamma-Aminobutírico/fisiologíaRESUMEN
In light of the postulated role of thyrotropin-releasing hormone (TRH) as an endogenous anti-depressant, 56 refractory mood-disordered patients and 34 healthy adult control subjects underwent lumbar puncture for cerebrospinal fluid (CSF) TRH analysis. By two-way analysis of variance, there was no difference between CSF TRH in patients (as a group or by diagnostic subtype) and control subjects (n = 90, F = 0.91, df = 2.84, P = 0.41). There was, however, a CSF TRH gender difference (females, 2.95 pg/ml; males, 3.98 pg/ml; n = 90, F = 4.11, df = 1.84, P < 0.05). A post hoc t-test revealed the greatest gender difference in the bipolar group (t = 2.52, P < 0.02). There was no significant difference in CSF TRH in "ill" vs. "well" state (n = 20, P = 0.41). The role of elevated levels of CSF TRH in affectively ill men--or the role of decreased levels of CSF TRH in affectively ill women--remains to be investigated but could be of pathophysiological relevance.