RESUMEN
PURPOSE: To evaluate the effect of reconstructing inferior alveolar nerve and preserving the sensation of lower lip and chin in repairing mandibular defect by simultaneous neuralized iliac bone flap. METHODS: Patients with continuous mandibular defects requiring reconstruction were randomly assigned to the innervated(IN) group and the control(CO) group by random number table. In the IN group, the deep circumflex iliac artery and recipient vessels were anastomosed microscopically during mandible reconstruction, and the ilioinguinal nerve(IN), mental nerve(MN) and inferior alveolar nerve(IAN) were anastomosed at the same time. In the CO group, only vascular anastomosis was performed without nerve reconstruction. During the operation, the nerve electrical activity after nerve anastomosis was detected by nerve monitor, and the sensory recovery of lower lip was recorded by two-point discrimination(TPD), current perception threshold (CPT) and Touch test sensory evaluator(TTSE) test. SPSS 26.0 software package was used for data analysis. RESULTS: According to the inclusion and exclusion criteria, a total of 20 patients were included, with 10 patients in each group. All the flaps survived in both groups, and no serious complications such as flap crisis occurred, and no obvious complications occurred in the donor site. The results of TPD test, CPT test and TTSE test all indicated that the degree of postoperative hypoesthesia in the IN group was less(Pï¼0.05). CONCLUSIONS: Simultaneous nerve anastomosis vascularized iliac bone flap can effectively preserve the feeling of lower lip and improve the postoperative quality of life of patients. It is a safe and effective technique.
Asunto(s)
Enfermedades Mandibulares , Reconstrucción Mandibular , Colgajos Quirúrgicos , Humanos , Calidad de Vida , Enfermedades Mandibulares/cirugía , Arteria Ilíaca/inervación , Labio/cirugía , Mentón/cirugía , Anastomosis Quirúrgica , SensaciónRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Perivascular neuropathy was reported to involve in the vascular disorders associated with diabetes. The dried rhizomes of Coptis chinensis Franch. (Latin name: Coptidis Rhizoma; common name: Huang Lian in China), used frequently in Traditional Chinese medicine to treat diabetes (Xiaoke), have been confirmed to possess beneficial effects on diabetic peripheral neuropathy by modern clinical and pharmacological studies. Berberine (BBR), the main effective component of Huang Lian in the treatment of diabetes, is reported to ameliorate diabetic central and peripheral neuropathy. However, the effects of BBR on nerve function of mesenteric and iliac arteries are unclear. AIM OF THE STUDY: To investigate the effects of BBR on the diabetes-induced changes in nitrergic and adrenergic function in mesenteric and iliac arteries. MATERIALS AND METHODS: In this study, the animals were randomized into three groups: control rats, diabetic rats, and diabetic rats gavaged with BBR. We established diabetic rat model using intraperitoneal injection of streptozotocin (STZ, 55â¯mgâ¯kg-1). Two weeks after model establishment, those in the BBR-treated groups were gavaged with berberine chloride (Sichuan Xieli Fharmaceutical. Co., Ltd; 200â¯mg·kg-1·day-1) diluted in distilled water for another 2 weeks. The superior mesenteric artery and iliac artery were excised. Electric field stimulation (EFS) was used to induce arterial vasoconstriction and explore (1) the diabetes-induced changes in neurogenic function of the superior mesenteric artery and iliac artery; (2) the effects of BBR on neurovascular dysfunction in the early stage of STZ-induced diabetic rats. Nitric oxide (NO) and noradrenaline (NA) released from the nitrergic and adrenergic nerves were quantified using fluorescence assays and ELISA, respectively. RESULTS: EFS induced frequency-dependent vasoconstrictions in both superior mesenteric and iliac artery, and the contractile responses of arteries were abolished by 0.1⯵mol·L-1 tetrodotoxin (TTX), or inhibited by 1⯵mol·L-1 phentolamine or increased by 0.1â¯mmol·L-1 Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME). In superior mesenteric artery, but not in iliac artery, the changes of contractile responses with L-NAME were significantly decreased in diabetic rats, and NO release was less also. In contrast, in iliac artery of diabetic rats, but not in superior mesenteric artery, the changes of contractile responses with phentolamine were increased, and NA release was increased significantly. All these changes in diabetic rats on both superior mesenteric artery and iliac artery were reversed by treated with BBR. CONCLUSIONS: In the STZ-induced early diabetic rats, neural control of mesenteric and iliac vasomotor tone are altered differently. The diminished nitrergic nerve in superior mesenteric artery and enhanced adrenergic nerve in iliac artery both contributed to increased vasocontrictor responses. All these changes in diabetic rats were reversed by BBR, suggesting a novel mechanism of BBR in balance of neural regulation of vascular tone.
Asunto(s)
Neuronas Adrenérgicas/efectos de los fármacos , Berberina/farmacología , Diabetes Mellitus Experimental/fisiopatología , Arteria Ilíaca/efectos de los fármacos , Arterias Mesentéricas/efectos de los fármacos , Neuronas Nitrérgicas/efectos de los fármacos , Neuronas Adrenérgicas/fisiología , Animales , Diabetes Mellitus Experimental/metabolismo , Arteria Ilíaca/inervación , Arteria Ilíaca/fisiología , Masculino , Arterias Mesentéricas/inervación , Arterias Mesentéricas/fisiología , Neuronas Nitrérgicas/fisiología , Óxido Nítrico/metabolismo , Norepinefrina/metabolismo , Ratas Sprague-DawleyRESUMEN
Our previous studies showed that stimulation of adenosine A(1) receptors located in the nucleus of the solitary tract (NTS) exerts counteracting effects on the iliac vascular bed: activation of the adrenal medulla and ß-adrenergic vasodilation vs. sympathetic and vasopressinergic vasoconstriction. Because NTS A(1) adenosine receptors inhibit baroreflex transmission in the NTS and contribute to the pressor component of the HDR, we hypothesized that these receptors also contribute to the redistribution of blood from the visceral to the muscle vasculature via prevailing sympathetic and vasopressinergic vasoconstriction in the visceral (renal and mesenteric) vascular beds and prevailing ß-adrenergic vasodilation in the somatic (iliac) vasculature. To test this hypothesis, we compared the A(1) adenosine-receptor-mediated effects of each vasoactive factor triggered by NTS A(1) adenosine receptor stimulation [N(6)-cyclopentyladenosine (CPA), 330 pmol in 50 nl] on the regional vascular responses in urethane/chloralose-anesthetized rats. The single-factor effects were separated using adrenalectomy, ß-adrenergic blockade, V(1) vasopressin receptor blockade, and sinoaortic denervation. In intact animals, initial vasodilation was followed by large, sustained vasoconstriction with smaller responses observed in renal vs. mesenteric and iliac vascular beds. The initial ß-adrenergic vasodilation prevailed in the iliac vs. mesenteric and renal vasculature. The large and sustained vasopressinergic vasoconstriction was similar in all vascular beds. Small sympathetic vasoconstriction was observed only in the iliac vasculature in this setting. We conclude that, although A(1) adenosine-receptor-mediated ß-adrenergic vasodilation may contribute to the redistribution of blood from the visceral to the muscle vasculature, this effect is overridden by sympathetic and vasopressinergic vasoconstriction.
Asunto(s)
Fibras Adrenérgicas/metabolismo , Hemodinámica , Arteria Ilíaca/inervación , Arterias Mesentéricas/inervación , Músculo Esquelético/irrigación sanguínea , Receptor de Adenosina A1/metabolismo , Receptores Adrenérgicos beta/metabolismo , Arteria Renal/inervación , Núcleo Solitario/metabolismo , Agonistas del Receptor de Adenosina A1/farmacología , Médula Suprarrenal/inervación , Médula Suprarrenal/metabolismo , Médula Suprarrenal/cirugía , Adrenalectomía , Fibras Adrenérgicas/efectos de los fármacos , Antagonistas Adrenérgicos beta/farmacología , Animales , Antagonistas de los Receptores de Hormonas Antidiuréticas , Desnervación Autonómica , Hemodinámica/efectos de los fármacos , Antagonistas de Hormonas/farmacología , Arteria Ilíaca/efectos de los fármacos , Arteria Ilíaca/metabolismo , Masculino , Arterias Mesentéricas/efectos de los fármacos , Arterias Mesentéricas/metabolismo , Ratas , Ratas Sprague-Dawley , Receptor de Adenosina A1/efectos de los fármacos , Receptores Adrenérgicos beta/efectos de los fármacos , Receptores de Vasopresinas/metabolismo , Flujo Sanguíneo Regional , Arteria Renal/efectos de los fármacos , Arteria Renal/metabolismo , Circulación Renal , Núcleo Solitario/efectos de los fármacos , Circulación Esplácnica , Factores de Tiempo , Vasoconstricción , Vasodilatación , Vasopresinas/metabolismoRESUMEN
Our previous study showed that stimulation of adenosine A(1) receptors located in the nucleus of the solitary tract (NTS) exerts counteracting effects on the iliac vascular bed: activation of the adrenal medulla and beta-adrenergic vasodilation versus vasoconstriction mediated by neural and unknown humoral factors. In the present study we investigated the relative contribution of three major potential humoral vasoconstrictors: vasopressin, angiotensin II, and norepinephrine in this response. In urethane-chloralose anesthetized rats we compared the integral changes in iliac vascular conductance evoked by microinjections into the NTS of the selective A(1) receptor agonist N(6)-cyclopentyladenosine (CPA; 330 pmol in 50 nl) in intact (Int) animals and following: V(1) vasopressin receptor blockade (VX), angiotensin II AT(1) receptor blockade (ATX), bilateral adrenalectomy + ganglionic blockade (ADX + GX; which eliminated the potential increases in circulating norepinephrine and epinephrine), ADX + GX + VX and ADX + GX + VX + ATX. In Int animals, stimulation of NTS A(1) adenosine receptors evoked typical variable responses with prevailing pressor and vasoconstrictor effects. VX reversed the responses to depressor ones. ATX did not significantly alter the responses. ADX + GX accentuated pressor and vasoconstrictor responses, whereas ADX + GX + VX and ADX + GX + VX + ATX virtually abolished the responses. Stimulation of NTS A(1) adenosine receptors increased circulating vasopressin over fourfold (26.4 + or - 10.4 vs. 117.0 + or - 19 pg/ml). These data strongly suggest that vasopressin is a major vasoconstrictor factor opposing beta-adrenergic vasodilation in iliac vascular responses triggered by stimulation of NTS A(1) adenosine receptors, whereas angiotensin II and norepinephrine do not contribute significantly to the vasoconstrictor responses.
Asunto(s)
Angiotensina II/metabolismo , Barorreflejo , Arteria Ilíaca/inervación , Músculo Esquelético/irrigación sanguínea , Norepinefrina/metabolismo , Receptor de Adenosina A1/metabolismo , Núcleo Solitario/metabolismo , Vasoconstricción , Vasopresinas/metabolismo , Adenosina/administración & dosificación , Adenosina/análogos & derivados , Agonistas del Receptor de Adenosina A1 , Adrenalectomía , Bloqueadores del Receptor Tipo 1 de Angiotensina II/administración & dosificación , Animales , Antagonistas de los Receptores de Hormonas Antidiuréticas , Arginina Vasopresina/administración & dosificación , Arginina Vasopresina/análogos & derivados , Barorreflejo/efectos de los fármacos , Presión Sanguínea , Frecuencia Cardíaca , Miembro Posterior , Losartán/administración & dosificación , Masculino , Microinyecciones , Ratas , Ratas Sprague-Dawley , Receptor de Angiotensina Tipo 1/efectos de los fármacos , Receptor de Angiotensina Tipo 1/metabolismo , Receptores de Vasopresinas/metabolismo , Flujo Sanguíneo Regional , Núcleo Solitario/efectos de los fármacos , Simpatectomía , Factores de Tiempo , Vasoconstricción/efectos de los fármacos , Vasopresinas/sangreRESUMEN
Skeletal muscle vasculature of the hindlimb is innervated by a sympathetic noncholinergic vasodilator system. The aim of this study was to determine whether this vasodilator system may represent postganglionic lumbar sympathetic neurons that synthesize and release nitric oxide (NO) or related NO-containing factors. We examined whether NO synthase (NOS)-positive postganglionic lumbar nerves innervate the hindlimb vasculature of the rat and whether the hindlimb vasodilation produced by electrical stimulation of the lumbar sympathetic chain of anesthetized rats is reduced after the systemic administration of the specific inhibitor of neuronal NOS 7-nitroindazole (7-NI). Subpopulations of lumbar sympathetic cell bodies stained intensely for NOS. Postganglionic fibers and varicosities within the iliac and femoral arteries also stained for NOS. Double ligation of the lumbar chain demonstrated that NOS was transported from the cell bodies toward the peripheral terminals. Low-intensity electrical stimulation of the lumbar chain produced a pronounced hindlimb vasodilation that was markedly diminished by pretreatment with 7-NI (45 mg/kg i.v.). In contrast, the vasodilator potency of acetylcholine and S-nitrosocysteine were augmented by 7-NI. These results suggest that postganglionic lumbar sympathetic neurons may synthesize and release NO-containing factors.
Asunto(s)
Miembro Posterior/irrigación sanguínea , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico/fisiología , S-Nitrosotioles , Sistema Nervioso Simpático/fisiología , Acetilcolina/farmacología , Animales , Presión Sanguínea/efectos de los fármacos , Cisteína/análogos & derivados , Cisteína/farmacología , Estimulación Eléctrica , Endotelio Vascular/fisiología , Inhibidores Enzimáticos/farmacología , Técnica del Anticuerpo Fluorescente Indirecta , Ganglios Simpáticos/enzimología , Arteria Ilíaca/inervación , Indazoles/farmacología , Masculino , Óxido Nítrico Sintasa/antagonistas & inhibidores , Ratas , Ratas Sprague-Dawley , Flujo Sanguíneo Regional/efectos de los fármacos , Sistema Nervioso Simpático/enzimología , Resistencia Vascular/efectos de los fármacos , Vasodilatación/efectos de los fármacosRESUMEN
Somatostatin is a general inhibitory hormone that exerts its effects through five functionally distinct receptor subtypes (SSTR1-5). Somatostatin analogues have been shown to be effective in inhibiting intimal hyperplasia after balloon induced vascular injury. However, the exact SSTR subtype responsible for the inhibitory effect of somatostatin on intimal hyperplasia is unknown. The purpose of this study was to define the presence and abundance of SSTR subtypes in a rat iliac balloon injury model of intimal hyperplasia. Transaortic balloon injury of the rat iliac artery was carried out. Rats were sacrificed at 48 h, 1 week, and 1 month postinjury, and perfusion fixed and stained with antibodies against SSTR2, 3, and 5. SSTR2 was identified on the intimal surfaces of normal and injured vessels. SSTR2 immunoreactivity was more prominent at 1 week and 1 month postinjury compared with 48 h postinjury. There was no immunostaining with SSTR3 and SSTR5 antibodies. The results show that SSTR2 is expressed on endothelial cells in normal and injured rat vessels. Its abundance in the injured vessel was increased up to 1 month postinjury.
Asunto(s)
Cateterismo/efectos adversos , Arteria Ilíaca/lesiones , Receptores de Somatostatina/biosíntesis , Túnica Íntima/patología , Animales , Anticuerpos Monoclonales , Biomarcadores , Endotelio Vascular/química , Endotelio Vascular/inervación , Arteria Ilíaca/inervación , Arteria Ilíaca/ultraestructura , Masculino , Proteínas del Tejido Nervioso/análisis , Proteínas del Tejido Nervioso/inmunología , Nervios Periféricos/química , Ratas , Ratas Wistar , Receptores de Somatostatina/análisis , Receptores de Somatostatina/inmunología , Tioléster Hidrolasas/análisis , Tioléster Hidrolasas/inmunología , Factores de Tiempo , Túnica Íntima/química , Túnica Íntima/inervación , Ubiquitina TiolesterasaRESUMEN
OBJECTIVE: To investigate neurogenic control of uterine and iliac arterial tone with reference to nerve-derived nitric oxide. DESIGN: Mechanisms underlying the response to perivascular nerve stimulation were studied under alpha-adrenoceptor blockade. METHODS: Mechanical responses to nerve stimulation by nicotine were isometrically recorded in isolated canine uterine and iliac arterial strips. Nitric oxide synthase was stained immunohistochemically. RESULTS: The arterial strips responded to nicotine mainly with a contraction, which was reversed to a relaxation by prazosin. The responses were abolished by hexamethonium. The relaxation was not influenced by timolol and atropine but was suppressed by NG-nitro-L-arginine, a nitric oxide synthase inhibitor; the inhibition was reversed by L-arginine. Internal iliac arterial strips also responded to nicotine with a relaxation under prazosin treatment, the magnitude of which was appreciably less than that in the uterine artery. Histochemical study demonstrated that perivascular nerve fibres exhibit nitric oxide synthase immunoreactivity. CONCLUSION: Canine uterine arteries are innervated by adrenergic, vasoconstrictor and nitroxidergic vasodilator nerves, and the neurogenic vasodilation is evidently more marked than that in other canine arteries, including the iliac artery.
Asunto(s)
Sistema Nervioso Autónomo/fisiología , Arteria Ilíaca/inervación , Óxido Nítrico Sintasa/fisiología , Útero/irrigación sanguínea , Vasodilatación/fisiología , Animales , Sistema Nervioso Autónomo/efectos de los fármacos , Perros , Femenino , Estimulantes Ganglionares/farmacología , Arteria Ilíaca/efectos de los fármacos , Arteria Ilíaca/metabolismo , Inmunohistoquímica , Nicotina/farmacología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Útero/efectos de los fármacos , Útero/metabolismoRESUMEN
BACKGROUND: We have observed persistent desensitization to exogenous norepinephrine after balloon injury. We postulated that this desensitization may be due to a local increase in the release of neuronal norepinephrine. METHODS AND RESULTS: New Zealand White rabbits underwent left iliac artery angioplasty; 4 weeks later, both iliac arteries were harvested. Maximal response to exogenous norepinephrine was reduced in injured compared with noninjured vessels (12.3 +/- 1.0 g versus 10.3 +/- 1.5 g; n = 7, P = .056). By contrast, response to electrical stimulation (to induce neuronal norepinephrine release) was significantly greater in injured tissues (36 +/- 7% versus 14 +/- 3%; values expressed as percent of maximal contraction to exogenous norepinephrine; P = .025). Direct measurement of tissue norepinephrine revealed a threefold increase 4 weeks after injury (1236 +/- 410 versus 466 +/- 97 pg/mg; injured versus noninjured). To determine if desensitization to exogenous norepinephrine was due to a persistent increase in neuronal norepinephrine release, the experiments were repeated after chemical sympatholysis using 6-hydroxydopamine (6-OHDA) (65 mg/kg). To determine if activation of vascular angiotensin II contributed to facilitation of adrenergic neurotransmission, other animals received ramipril (RAM; 1 mg/kg per day). Both treatments were initiated 7 days before angioplasty. In the 6-OHDA group there was no evidence of desensitization, judged by maximal response to exogenous norepinephrine (7.5 +/- 0.6 versus 7.5 +/- 0.8, noninjured versus injured). Similar results were obtained in RAM animals (9.9 +/- 0.8 versus 9.6 +/- 1.2, noninjured versus injured). CONCLUSIONS: This is the first study to demonstrate enhanced adrenergic neurotransmission after balloon injury. The facilitation of adrenergic neurotransmission may be due to increased local concentrations of angiotensin II and is associated with desensitization to exogenous norepinephrine.
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Cateterismo/efectos adversos , Arteria Ilíaca/lesiones , Arteria Ilíaca/inervación , Sistema Nervioso Simpático/fisiopatología , Transmisión Sináptica , Angiotensina II/fisiología , Animales , Arteria Ilíaca/metabolismo , Masculino , Norepinefrina/metabolismo , Norepinefrina/farmacología , Conejos , Simpatectomía QuímicaRESUMEN
The aim of the work was to concretize ideas of the anatomy of extraintramural nerve plexuses along the course of large iliac vessels. Three nerves with the diameter 0.6-2 mm were revealed running from the iliac plexus to the paravasal fat. Topographic anatomical characteristics of these formations and their interrelations with the well-known branches of the lumbar plexus are given with special reference to practical value of the results obtained. The relation of nerves of the paravasal fat to adventitia of the vessels, lymph nodes, fascial and muscular formations was studied.
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Tejido Adiposo/inervación , Arteria Ilíaca/inervación , Vena Ilíaca/inervación , Adulto , Femenino , Técnicas Histológicas , Humanos , MasculinoRESUMEN
In recent years pedicled and microvascular free muscle flaps, myocutaneous flaps, and vascularized bone grafts have become well accepted reconstructive techniques in the management of complex defects. The deep circumflex iliac artery-based internal oblique muscle pedicle flap, internal oblique free muscle pedicle flap, internal oblique free muscle flap, and the internal oblique-iliac crest microvascular free flap are the latest additions to the reconstructive surgeons' armamentarium. This report describes the surgical anatomy of the internal oblique muscle and the deep circumflex iliac artery from a practical viewpoint with particular emphasis on the vascular basis of the above mentioned flaps.
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Músculos Abdominales/irrigación sanguínea , Colgajos Quirúrgicos , Músculos Abdominales/inervación , Cadáver , Humanos , Arteria Ilíaca/inervación , Vena Ilíaca/inervación , XerorradiografíaRESUMEN
Electrostimulation was used to study the neuroanatomy and physiology of penile erection in dogs and monkeys. The canine spinal nuclei responsible for penile erection, identified by the retrograde horseradish peroxidase transport technique after verification of the cavernous nerves with neurostimulation, were mediolateral autonomic neurons at T12-L3 and S1-S3. The erection induced by electrostimulation of the cavernous nerves is the result of increased arterial flow, relaxation of cavernous muscles, and venous outflow restriction. Study of electrostimulation in dogs and monkeys is invaluable for the understanding of the complex neurophysiology of human penile erection.
Asunto(s)
Eyaculación , Pene/inervación , Animales , Sistema Nervioso Autónomo/fisiología , Perros , Estimulación Eléctrica , Arteria Ilíaca/inervación , Macaca mulatta , Macaca nemestrina , Masculino , Pene/irrigación sanguínea , Nervios Periféricos/fisiología , Flujo Sanguíneo Regional , Médula Espinal/fisiología , Venas/inervaciónRESUMEN
The neural formations of intact rabbit major arteries and nerves of the same arteries in rabbits with the II and IV stages of the malignant Brown--Pearce tumor have been studied. Periarterial neural fasciculi, fibers and terminal branches have been revealed. According to ultrastructure of their cytoplasmic matrix, they can be divided into adrenergic, cholinergic or sensitive. When the malignant tumor is growing, the arterial neural formations undergo certain distrophic-destructive changes; they are especially pronounced in the membranous structures of the neural elements. Their cytoplasmic and basal membranes are partly or completely destroyed. In mitochondria the matrix is altered, some of them are vacuolized. Neurotubules and vesicles change their form and size and are partly destroyed. Membranous structures of lemmocytes are altered. The electron microscopic investigation adds something new to our data on ultrastructural changes in the arterial neural formations under growth of the malignant tumor previously obtained by means of neurohistological and neurohistochemical methods.
Asunto(s)
Arterias/inervación , Carcinoma de Brown-Pearce/patología , Nervios Periféricos/ultraestructura , Animales , Aorta/inervación , Arteria Ilíaca/inervación , Microscopía Electrónica , Terminaciones Nerviosas/ultraestructura , Fibras Nerviosas/ultraestructura , Conejos , Arteria Renal/inervaciónAsunto(s)
Aorta Abdominal/cirugía , Arteria Ilíaca/cirugía , Pene/fisiología , Neoplasias Testiculares/cirugía , Factores de Edad , Aorta Abdominal/inervación , Humanos , Arteria Ilíaca/inervación , Escisión del Ganglio Linfático , Masculino , Arterias Mesentéricas/inervación , Pene/inervación , SimpatectomíaRESUMEN
Electrical stimulation of the "Defence Area" of the hypothalamus in anaesthetized cats was accomplished by stereotaxic placement of bipolar stainless steel electrodes; the spinal cord was sectioned at L4. The muscle blood flow in one hind limb was recorded with an electromagnetic flowmeter. Increases of between 100% and 300% were observed during hypothalamic stimulation. Electroneurographic recordings from small nerve filaments supplying tibialis anterior muscle revealed two populations of neurones whose activity was abolished by lumbar sympathectomy. It appears that the increased blood flow in skeletal muscle during stimulation of the hypothalamic "Defence Area" is brought about by a simultaneous inhibition of vasoconstrictor activity and increase in cholinergic vasodilator discharge.