RESUMO
There is growing evidence that the nervous system influences spinal cord vasculature. However, most descriptions of the spinal cord have paid little attention to this important aspect. We reviewed the literature on the innervation of spinal cord vessels with an emphasis on findings that may be applicable to human medicine. Multiple neurotransmitters and competing theories have been implicated in the neural regulation of spinal cord blood vessels. Identifying valid mechanisms of pathogenesis could be beneficial to human patients with spinal cord lesions. We discuss the various findings on the neural mechanisms behind spinal cord blood flow. Further investigation is warranted due to the current emphasis on comparative animal studies without corresponding corroborative human findings.
Assuntos
Vasos Sanguíneos/inervação , Medula Espinal/irrigação sanguínea , Vasos Sanguíneos/anatomia & histologia , Vasos Sanguíneos/patologia , Humanos , Fluxo Sanguíneo Regional , Medula Espinal/anatomia & histologia , Medula Espinal/patologia , Doenças da Medula Espinal/patologiaAssuntos
Anemia Falciforme/complicações , Sistema Nervoso Autônomo/fisiopatologia , Vasos Sanguíneos/inervação , Vasos Sanguíneos/fisiopatologia , Doenças Vasculares/etiologia , Doenças Vasculares/fisiopatologia , Vasos Sanguíneos/patologia , Humanos , Índice de Gravidade de Doença , Doenças Vasculares/diagnósticoRESUMO
Estudos têm demonstrado limitações no conhecimento de acadêmicos e profissionais da saúde sobre diversas condições clínicas. Entretanto, são poucas as investigações na área das ciências cardiovasculares. Objetivo: Identificar e descrever o nível de conhecimento dos formandos em Fisioterapia sobre insuficiênciavenosa crônica (IVC). Métodos: Estudo observacional descritivo e transversal, realizado com formandos do último ano da graduação em Fisioterapia, selecionados aleatoriamente, de seis instituições de ensino superior. Os dados foram obtidos por meio de questionário estruturado autoaplicável, abordando questões sobre a formação acadêmica, aspectos clínicos e intervenções fisioterapêuticas na IVC. Os estudantes foram agrupados em: FSDA - faculdades que não oferecem a disciplina Angiologia; FPNE - faculdades que oferecem a disciplina Angiologia, por professor não especialista; e FPE - faculdades que oferecem a disciplina Angiologia, por professor especialista. Resultados: Foram avaliados 101 graduandos. Destes, apenas 4,9% tinham conhecimento de todas as técnicas emétodos para diagnosticar IVC e 44,0% não citaram o exame clínico como avaliação diagnóstica. Dos 35 alunos dasFPNE, 18 (51,0%) também não assinalaram o exame clínico e 31,0% citaram métodos incorretos de diagnóstico IVC. Dos 19 alunos do grupo FSDA, 74,0% não optaram pela compressão elástica como medida de tratamento. Conclusão: Conclui-se que os graduandos avaliados apresentaram déficit de conhecimento em relação aosprincipais métodos de diagnóstico e tratamentos fisioterapêuticos para a insuficiência venosa crônica...
Studies have shown limitations in the knowledge of academics and health professionals on a variety of clinical conditions. However, there is little research in the field of cardiovascular sciences. Objective: To identify and describe the level of knowledge of Physiotherapy graduates on chronic venous insufficiency (CVI).Methods: Descriptive cross-sectional observational study with graduates in the last year of physiotherapy undergraduate studies randomly selected from six higher education institutions. Data were collected through a self-administered structured questionnaire addressing academic education, clinical aspects and physiotherapy interventions on CVI. The students were grouped into: FSDA - universities where Angiology is not taught; FPNE - universities where a non-specialist professor teaches Angiology; and FPE - universities where a specialist professor teaches Angiology. Results: The evaluation covered 101 graduates. Of these, only 4.9% were familiar with of all the techniques and methods to diagnose CVI and 44.0% did not mention clinical examination as diagnostic evaluation. Of the 35 FPNE students, 18 (51.0%) did not mention clinical examination and 31.0% mentioned incorrect CVI diagnosing methods. Of the 19 FSDA students, 74.0% did not choose elastic compression as a means of treatment.Conclusion: It was concluded that the evaluated graduates presented little knowledge on the main physiotherapy treatments and diagnostic methods for chronic venous insufficiency...
Assuntos
Humanos , Masculino , Feminino , Modalidades de Fisioterapia/métodos , Insuficiência Venosa/complicações , Insuficiência Venosa/terapia , Reabilitação/métodos , Anamnese/métodos , Diagnóstico , Epidemiologia Descritiva , Estudo Observacional , Capacitação Profissional , Pessoal de Saúde/educação , Procedimentos Cirúrgicos Cardíacos/métodos , Vasos Sanguíneos/fisiopatologia , Vasos Sanguíneos/inervaçãoRESUMO
Several lines of evidence have shown an association of diabetes with a catecholamines' aberrant homeostasis involving a drastic change in the expression of adrenoceptors. This homeostatic alteration includes, among other things, atypical actions of α2 -adrenoceptor agonists within central and peripheral α2 -adrenoceptors (e.g. profound antinociceptive effects in diabetic subjects). Hence, this study investigated the pharmacological profile of the α2 -adrenoceptor subtypes that inhibit the vasopressor sympathetic out-flow in streptozotocin-pre-treated (diabetic) pithed rats. For this purpose, B-HT 933 (up to 30 µg/kg min) was used as a selective α2 -adrenoceptor agonist and rauwolscine as a non-selective α2A/2B/2C -adrenoceptor antagonist; in addition, BRL 44408, imiloxan and JP-1302 were used as subtype-selective α2A -, α2B - and α2C -adrenoceptor antagonists, respectively (all given i.v.). I.v. continuous infusions of B-HT 933 inhibited the vasopressor responses induced by electrical sympathetic stimulation without affecting those by i.v. bolus injections of noradrenaline in both normoglycaemic and diabetic rats. Interestingly, the ED50 for B-HT 933 in diabetic rats (25 µg/kg min) was almost 1-log unit greater than that in normoglycaemic rats (3 µg/kg.min). Moreover, the sympatho-inhibition induced by 10 µg/kg min B-HT 933 in diabetic rats was (i) abolished by 300 µg/kg rauwolscine or 100 and 300 µg/kg BRL 44408; (ii) partially blocked by 1000 µg/kg imiloxan; and (iii) unchanged by 1000 µg/kg JP-1302. Our findings, taken together, suggest that B-HT 933 has a less potent inhibitory effect on the sympathetic vasopressor responses in diabetic (compared to normoglycaemic) rats and that can probably be ascribed to a down-regulation of α2C -adrenoceptors.
Assuntos
Vasos Sanguíneos/inervação , Diabetes Mellitus Experimental/metabolismo , Receptores Adrenérgicos alfa 2/metabolismo , Sistema Nervoso Simpático/metabolismo , Vasoconstrição , Agonistas alfa-Adrenérgicos/farmacologia , Antagonistas Adrenérgicos alfa/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Vasos Sanguíneos/efeitos dos fármacos , Estado de Descerebração , Diabetes Mellitus Experimental/fisiopatologia , Estimulação Elétrica , Masculino , Ratos Wistar , Receptores Adrenérgicos alfa 2/efeitos dos fármacos , Sistema Nervoso Simpático/fisiopatologia , Vasoconstrição/efeitos dos fármacosRESUMO
Imidazoline derivatives (e.g. clonidine and moxonidine) and alpha(2)-adrenoceptor agonists (e.g. B-HT 933) have been shown to inhibit sympathetically-induced [(3)H]noradrenaline release in several isolated blood vessels. The present study has compared the potential capability of agonists at imidazoline I(1/2) receptors and/or alpha(1/2)-adrenoceptors to inhibit the sympathetically-induced vasopressor responses in pithed rats. For this purpose, male Wistar rats were pithed and prepared for measurement of diastolic blood pressure and heart rate. Then, the vasopressor responses induced by either selective electrical stimulation (2 ms, 60 V; 0.03, 0.1, 0.3, 1 and 3 Hz) of the vascular sympathetic outflow (T(7)-T(9)) or i.v. bolus injections of exogenous noradrenaline (0.03, 0.1, 0.3, 1 and 3 microg/kg) were determined before and during i.v. continuous infusions of the agonists B-HT 933 (alpha(2)), clonidine (alpha(2), I(1)), moxonidine (alpha(2), I(1)), cirazoline (alpha(1), I(2)), agmatine (putative endogenous ligand of imidazoline receptors) and methoxamine (alpha(1)), or equivalent volumes of physiological saline. Electrical sympathetic stimulation elicited frequency-dependent vasopressor responses which were significantly inhibited during the continuous infusions of B-HT 933, clonidine, moxonidine, cirazoline and agmatine, but not of physiological saline. Interestingly, the vasopressor responses to exogenous noradrenaline, which remained unaffected during the infusions of physiological saline, B-HT 933, moxonidine, cirazoline and agmatine, were significantly blocked during the infusions of clonidine or methoxamine. These results suggest that B-HT 933, moxonidine, cirazoline and agmatine induced a prejunctional inhibition of the vasopressor sympathetic outflow in pithed rats, whilst clonidine inhibited the vasopressor sympathetic outflow by both prejunctional and postjunctional mechanisms.
Assuntos
Pressão Sanguínea/efeitos dos fármacos , Vasos Sanguíneos/inervação , Imidazolinas/farmacologia , Sistema Nervoso Simpático/efeitos dos fármacos , Agonistas alfa-Adrenérgicos/administração & dosagem , Agonistas alfa-Adrenérgicos/farmacologia , Agmatina/administração & dosagem , Agmatina/farmacologia , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/farmacologia , Azepinas/administração & dosagem , Azepinas/farmacologia , Pressão Sanguínea/fisiologia , Clonidina/administração & dosagem , Clonidina/farmacologia , Estado de Descerebração , Relação Dose-Resposta a Droga , Estimulação Elétrica/métodos , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Imidazóis/administração & dosagem , Imidazóis/farmacologia , Receptores de Imidazolinas/agonistas , Imidazolinas/administração & dosagem , Injeções Intravenosas , Masculino , Metoxamina/administração & dosagem , Metoxamina/farmacologia , Ratos , Ratos Wistar , Sistema Nervoso Simpático/fisiologia , Sistema Vasomotor/efeitos dos fármacos , Sistema Vasomotor/fisiologiaRESUMO
BACKGROUND AND PURPOSE: Resistance blood vessels are innervated by sympathetic and primary sensory nerves, which modulate vascular tone through the release of noradrenaline and calcitonin gene-related peptide (CGRP), respectively. Moreover, electrical stimulation of the perivascular sensory outflow in pithed rats results in vasodepressor responses which are mainly mediated by CGRP release. The present study has investigated the role of alpha(2)-adrenoceptors in the inhibition of these vasodepressor responses. EXPERIMENTAL APPROACH: 144 pithed male Wistar rats were pretreated with hexamethonium (2 mg kg(-1) min(-1)) followed by i.v. continuous infusions of either methoxamine (15 and 30 microg kg(-1) min(-1)) or clonidine (3, 10 and 30 microg kg(-1) min(-1)). Under these conditions, electrical stimulation (0.56-5.6 Hz; 50 V and 2 ms) of the spinal cord (T(9)-T(12)) resulted in frequency-dependent decreases in diastolic blood pressure. KEY RESULTS: The infusion of clonidine (10 microg kg(-1) min(-1)), as compared to those of methoxamine (15 or 30 microg kg(-1) min(-1)), inhibited the vasodepressor responses to electrical stimulation without affecting those to i.v. bolus injections of alpha-CGRP (0.1-1 microg kg(-1)). This inhibition by clonidine was: (i) antagonized by 300 microg kg(-1) rauwolscine (alpha(2A/2B/2C)), 300 and 1000 microg kg(-1) BRL44408 (alpha(2A)), or 10 and 30 microg kg(-1) MK912 (alpha(2C)); and (ii) unaffected by 1 ml kg(-1) saline, 100 microg kg(-1) BRL44408, 3000 and 10,000 microg kg(-1) imiloxan (alpha(2B)) or 3 microg kg(-1) MK912. CONCLUSIONS AND IMPLICATIONS: The inhibition produced by 10 microg kg(-1) min(-1) clonidine on the vasodepressor (perivascular) sensory outflow in rats may be mainly mediated by prejunctional alpha(2A)/alpha(2C)-adrenoceptors.
Assuntos
Agonistas alfa-Adrenérgicos/farmacologia , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/inervação , Clonidina/farmacologia , Estado de Descerebração/fisiopatologia , Neurônios Aferentes/efeitos dos fármacos , Receptores Adrenérgicos alfa 2/fisiologia , Antagonistas Adrenérgicos alfa/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Peptídeo Relacionado com Gene de Calcitonina/farmacologia , Estimulação Elétrica , Frequência Cardíaca/efeitos dos fármacos , Imidazóis/farmacologia , Técnicas In Vitro , Isoindóis/farmacologia , Masculino , Quinolizinas/farmacologia , Ratos , Ratos Wistar , Receptores Adrenérgicos alfa 2/efeitos dos fármacos , Ioimbina/farmacologiaRESUMO
We studied the effects of a hypocaloric diet (D, n = 24, age: 32.2 +/- 1.4 yr, body mass index: 34.7 +/- 0.5 kg/m2) and a hypocaloric diet associated with exercise training (D + T, n = 25, age: 32.3 +/- 1.3 yr, body mass index: 32.9 +/- 0.4 kg/m2) on muscle metaboreflex control, muscle sympathetic nerve activity (MSNA, microneurography), blood pressure, and forearm blood flow (plethysmography) levels during handgrip exercise at 10% and 30% of maximal voluntary contraction in normotensive obese women. An additional 10 women matched by age and body mass index were studied as a nonadherent group. D or D + T significantly decreased body mass index. D or D + T significantly decreased resting MSNA (bursts/100 heartbeats). The absolute levels of MSNA were significantly lower throughout 10% and 30% exercise after D or D + T, although no change was found in the magnitude of response of MSNA. D + T, but not D, significantly increased resting forearm vascular conductance. D + T significantly increased the magnitude of the response of forearm vascular conductance during 30% exercise. D or D + T significantly increased MSNA levels during posthandgrip circulatory arrest when muscle metaboreflex is isolated. In conclusion, weight loss improves muscle metaboreflex control in obese women. Weight loss reduces MSNA, which seems to be centrally mediated. Weight loss by D + T increases forearm vascular conductance at rest and during exercise in obese individuals.
Assuntos
Exercício Físico/fisiologia , Músculo Esquelético/irrigação sanguínea , Obesidade/fisiopatologia , Reflexo/fisiologia , Sistema Nervoso Simpático/fisiologia , Redução de Peso/fisiologia , Adulto , Pressão Sanguínea/fisiologia , Vasos Sanguíneos/inervação , Vasos Sanguíneos/fisiologia , Ingestão de Energia/fisiologia , Feminino , Antebraço/irrigação sanguínea , Força da Mão/fisiologia , Humanos , Contração Muscular/fisiologia , Obesidade/dietoterapia , PletismografiaRESUMO
Previous studies have shown that chronic administration of oestrogen to prepubertal rats reduces the total content of noradrenaline in the uterine horn, abolishes myometrial noradrenergic innervation and reduces noradrenaline-fluorescence intensity of intrauterine perivascular nerve fibres. The mechanisms underlying these changes are not known. In the present study we have analysed the effects of prepubertal chronic oestrogen treatment on the synthesis of noradrenaline in the rat uterine sympathetic nerves using biochemical and immunohistochemical approaches. Tyrosine hydroxylase activity was evaluated biochemically, by measuring the in vivo accumulation of dihydroxyphenylalanine (DOPA) in the presence of a DOPA-decarboxylase inhibitor. In addition, nerve fibres were visualised immunohistochemically using antibodies against tyrosine hydroxylase (TH), dopamine-beta-hydroxylase (DbetaH) and the general marker protein gene product 9.5 (PGP 9.5). After chronic oestrogen treatment, the total content of noradrenaline of the uterine horn was reduced, whereas the total content of DOPA was increased. In controls, TH-immunoreactive, DbetaH-immunoreactive and PGP 9.5-immunoreactive nerve fibres were distributed in both the circular and longitudinal myometrial layers and in the blood vessels of the intran-myometrial region. After chronic oestrogen treatment the only fibres recognised by the three antibodies were those associated with the blood vessels, but no myometrial-associated fibres could be recognised. These results suggest that noradrenaline synthesis is selectively reduced in myometrial-associated uterine sympathetic nerves, but is preserved in perivascular sympathetic nerves. The increased DOPA levels measured after chronic exposure to oestrogen was interpreted as the consequence of the substantial increase in size and number of blood vessels observed in the uterus of oestrogen-treated animals. A possible neurodegenerative effect of oestrogen on myometrial sympathetic fibres is discussed.
Assuntos
Estradiol/análogos & derivados , Miométrio/irrigação sanguínea , Miométrio/inervação , Norepinefrina/biossíntese , Sistema Nervoso Simpático/metabolismo , Animais , Vasos Sanguíneos/inervação , Di-Hidroxifenilalanina/metabolismo , Dopamina beta-Hidroxilase/metabolismo , Estradiol/farmacologia , Feminino , Imuno-Histoquímica , Ratos , Ratos Wistar , Sistema Nervoso Simpático/enzimologia , Tioléster Hidrolases/metabolismo , Fatores de Tempo , Tirosina 3-Mono-Oxigenase/metabolismo , Ubiquitina TiolesteraseRESUMO
We have made an immunohistochemical study of the vomeronasal (VN) complex of 12-day-old rats to characterize the innervation of its blood vessels. The VN complex can be subdivided into rostral, middle and caudal segments, each one with a particular vascularization pattern. Several small vessels were associated with the rostral segment, whereas a large venous sinus ran along the middle and caudal segments. Immunostaining for alpha-smooth muscle actin demonstrated that the muscular sheath was asymmetric, with more cells layers in its lateral than in its medial walls. Nerves were demonstrated with antisera against protein gene product 9.5 (PGP), and against several molecules associated with specific classes of nerve fibers: the C-terminal peptide of neuropeptide Y (CPON), calcitonin gene-related peptide (CGRP), substance P (SP), galanin (GAL), vasoactive intestinal peptide (VIP) and neuronal nitric oxide synthase (NOS). The latter, was also studied with NADPH-diaphorase. Vascular associated fibers exhibited NOS-, CPON-, GAL-, CGRP-, SP- and VIP-immunoreactivity. Only the vessels of the rostral segment showed VIP-immunoreactive fibers. Each wall of the venous sinus exhibited different types of nerve fibers. CPON-, GAL-, CGRP- and SP-immunoreactive fibers concentrated in the medial wall, whereas NOS-immunoreactive ones concentrated in the lateral wall. This distribution of vascular fibers, plus the presence of sensory fibers exhibiting CGRP-, SP- and GAL-immunoreactivity within the pseudostratified epithelium of the VN tube, would be relevant to understand the operation of the pumping mechanism regulating influx and efflux from the VN tube.
Assuntos
Vasos Sanguíneos/inervação , Fibras Nervosas/química , Neuropeptídeos/análise , Órgão Vomeronasal/irrigação sanguínea , Animais , Feminino , Histocitoquímica , Imuno-Histoquímica , Masculino , Ratos , Ratos Sprague-Dawley , Órgão Vomeronasal/inervaçãoRESUMO
An immunohistochemical study of the nasal mucosa was done in pediatric patients attending an otorhinolaringology (ORL) clinic. The goal was a comparison between vascular innervation in patients with or without symptoms of chronic rhinitis. All patients had an indication for tonsillectomy prior to their inclusion in this study. Samples were obtained under general anesthesia at the time of programmed surgery and fixed in a paraformaldehyde-picric acid mixture. Cryostat sections were immunostained for the following neuronal markers: protein-gene product 9.5 (PGP), calcitonin gene- related peptide (CGRP), substance P (SP), and C-terminal peptide of neuropeptide Y (CPON). The following classes of vessels were identified: arteries, sinusoids, veins, and arteriovenous anastomoses (AVAs). As shown by immunostaining with the general neuronal marker PGP, each vessel type had a characteristic innervation pattern, differing in the amount of fibers and their distribution within the adventitial and muscle layers. Evaluation of PGP, CPON, and CGRP immunoreactivity patterns indicated that rhinitic arteries and AVAs displayed a richer innervation than did nonrhinitic blood vessels. Quantification of vascular PGP immunostaining confirmed the difference of vascular innervation between nonrhinitic and rhinitic patients. Fibers immunostained by CPON partially accounted for the rhinitic arterial hyperinnervation.