Effect of stimulation of nucleus raphe dorsalis on carotid blood flow. II. The cat

The dorsal raphe nucleus (DRN) and surrounding midbrain of 74 cats were stimulated both electrically and chemically, and carotid flows were measured with electromagnetic flow probes. Stimulation of the DRN caused a frequency-dependent decrease in common carotid vascular resistance, which was abolished by bilateral section of the facial nerve intracranially. Injection of DL-homocysteic acid into the DRN reproduced the effect of electrical stimulation, indicating that the responses arose from excitation of cell bodies within the DRN, not from fibers of passage. The responses were mediated entirely within the brain stem since they remained intact after high spinal cord section. The vasodilator response was blocked by the intravenous administration of the nicotinic ganglion blocker hexamethonium but not by the alpha-adrenoceptor blocker phentolamine. The responses were unaffected by intravenous administration of methysergide but were markedly reduced after depletion of central serotonin by pretreatment with the serotonin depletor, p-chlorophenylalanine. A poststimulus constrictor response was mediated by release of catecholamines from the adrenal medulla and was blocked by the alpha-adrenoceptor antagonist phentolamine. No response involved supracollicular mechanisms since they persisted after decerebration.

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Effect of stimulation of nucleus raphe dorsalis on carotid blood flow. I. The monkey

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1985.248.2.r257 ◽

1985 ◽

Vol 248 (2) ◽

pp. R257-R262 ◽

Cited By ~ 2

Author(s):

P. J. Goadsby ◽

R. D. Piper ◽

G. A. Lambert ◽

J. W. Lance

Keyword(s):

Facial Nerve ◽

External Carotid ◽

Blood Flows ◽

Beta Adrenoceptor ◽

Alpha Adrenoceptor ◽

Adrenoceptor Antagonist ◽

Muscarinic Cholinergic ◽

Raphe Dorsalis ◽

Carotid Circulation ◽

Stimulation Of

The dorsal raphe nucleus (DRN) and surrounding midbrain of 16 anaesthetized monkeys were stimulated electrically, and carotid blood flows were measured with electromagnetic flow probes. Stimulation of the DRN caused a frequency-dependent decrease (vasodilatation) in both internal and external carotid vascular resistance, which was abolished in both circulations by bilateral section of the facial nerve intracranially. These vasodilator responses were unaltered by intravenous administration of muscarinic cholinergic or by alpha- or beta-adrenoceptor antagonists. A postdilatation constrictor response, observed in the external carotid circulation, was blocked by the alpha-adrenoceptor antagonist phentolamine. It is concluded that projections of the DRN through the greater superficial petrosal branch of the facial nerve mediate vasodilatation in both internal and external carotid circulations.

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Effect of compound D-600 (methoxyverapamil) on gluconeogenesis and on acceleration of the process by α-adrenergic stimuli in rat kidney tubules

Biochemical Journal ◽

10.1042/bj1900283 ◽

1980 ◽

Vol 190 (2) ◽

pp. 283-291 ◽

Cited By ~ 9

Author(s):

E D Saggerson ◽

C A Carpenter

Keyword(s):

Renal Cortex ◽

Rat Kidney ◽

Sodium Lactate ◽

Kidney Tubules ◽

Alpha Adrenoceptor ◽

Adrenoceptor Antagonist ◽

Adrenoceptor Agonist ◽

Adrenoceptor Blocker ◽

Glucose Formation ◽

Stimulation Of

1. Tubule fragments were isolated from renal cortex of fed rats and glucose formation was measured after incubation with 5 mM-sodium lactate. 20 Compound D-600 (10-100 microM) decreased gluconeogenesis from lactate. This inhibition of the process by compound D-600 increased with increasing extracellular Ca2+ concentration, was overridden by noradrenaline and diminished by starvation for 24 h. 3. Inhibition of lactate-supported gluconeogenesis by compound D-600 was not prevented by the alpha 1-adrenoceptor antagonist thymoxamine. 4. Compound D-600 had little effect on gluconeogenesis from 2-oxoglutarate and increased gluconeogenesis from succinate. 5. Compound D-600 opposed stimulation of gluconeogenesis by noradrenaline or oxymetazoline (a selective alpha-adrenoceptor agonist) in a manner suggesting that compound D-600 is an alpha-adrenoceptor blocker. Oxymetazoline was more sensitive than noradrenaline to blockade by both compound D-600 and by the conventional alpha-adrenoceptor antagonist phentolamine. Noradrenaline became more sensitive to blockade by compound D-600 when extracellular Ca2+ was decreased. 6. Compound D-600 did not block stimulation of gluconeogenesis by angiotensin or cyclic AMP.

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Unmasking of sympathetic vasoconstriction of the coronary vessels after acute administration of reserpine to dogs

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y76-027 ◽

1976 ◽

Vol 54 (2) ◽

pp. 166-169 ◽

Cited By ~ 1

Author(s):

M. Szentiványi ◽

G. Kunos ◽

A. Juhász-Nagy

Keyword(s):

Intravenous Administration ◽

Sympathetic Innervation ◽

Coronary Vessels ◽

Acute Administration ◽

Coronary Vasodilation ◽

Sympathetic Vasoconstriction ◽

Constrictor Response ◽

Stimulation Of

Acute intravenous administration of reserpine or pretreatment of dogs with Segontin selectively abolished coronary vasodilation and unmasked a constrictor response to stimulation of the cardiac sympathetics. In view of earlier findings of separate coronary vasomotor and cardiostimulatory sympathetic innervation, the results are interpreted to indicate the existence of reserpine-resistant short (vasomotor) and reserpine-sensitive long (cardiostimulatory) sympathetic postganglionic neurons.

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Evidence for existence of postjunctional alpha 1- and alpha 2-adrenoceptors in cat pulmonary vascular bed

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1985.249.4.h891 ◽

1985 ◽

Vol 249 (4) ◽

pp. H891-H898

Author(s):

A. L. Hyman ◽

P. J. Kadowitz

Keyword(s):

Adrenergic Nerve ◽

Alpha Adrenoceptor ◽

Adrenoceptor Antagonist ◽

Vascular Bed ◽

Alpha Adrenoceptor Agonists ◽

Adrenoceptor Blocker ◽

Adrenoceptor Agonists ◽

Uk 14,304 ◽

6 Hydroxydopamine ◽

Pulmonary Vascular Bed

The subtypes of postjunctional alpha-adrenoceptors in the feline pulmonary vascular bed were studied using selective alpha-adrenoceptor agonists and antagonists. Under conditions of controlled pulmonary blood flow and constant left atrial pressure, intralobar injections of the alpha 1-adrenoceptor agonists, phenylephrine and methoxamine, and the alpha 2-adrenoceptor agonists, UK 14,304 and BHT 933, increased lobar arterial pressure in a dose-related manner. Prazosin, an alpha 1-adrenoceptor antagonist, reduced responses to phenylephrine and methoxamine to a greater extent than responses to UK 14,304 and BHT 933. Yohimbine, an alpha 2-adrenoceptor blocker, decreased responses to UK 14,304 and BHT 933 without altering responses to phenylephrine or methoxamine. The same pattern of blockade was observed in animals pretreated with 6-hydroxydopamine, an agent that destroys the integrity of adrenergic nerve terminals. However, in propranolol-treated animals, prazosin antagonized responses to phenylephrine and methoxamine without altering responses to UK 14,304 or BHT 933, and the selectivity of the blocking effects of yohimbine were preserved. Responses to intralobar injections of norepinephrine were markedly decreased by prazosin, whereas yohimbine had only a small effect. These data suggest the presence of both postjunctional alpha 1- and alpha 2-adrenoceptors mediating vasoconstriction in the pulmonary vascular bed. These results also indicate that the vasoconstrictor responses to injected norepinephrine in the cat pulmonary vascular bed are due mainly to activation of alpha 1-adrenoceptors.

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Nerve-induced nonadrenergic vasoconstriction and vasodilatation in skeletal muscle

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1990.258.5.h1334 ◽

1990 ◽

Vol 258 (5) ◽

pp. H1334-H1338 ◽

Cited By ~ 2

Author(s):

A. Ohlen ◽

M. G. Persson ◽

L. Lindbom ◽

L. E. Gustafsson ◽

P. Hedqvist

Keyword(s):

High Frequency ◽

Motor Nerve ◽

Low Frequency ◽

High Frequency Stimulation ◽

Alpha Adrenoceptor ◽

Adrenoceptor Antagonist ◽

Stimulation Parameters ◽

Low Frequency Stimulation ◽

Frequency Stimulation ◽

Stimulation Of

Intravital microscopy was used to study the effect of motor nerve stimulation on microvessel diameters in the rabbit tenuissimus muscle. Stimulation of the motor nerve (0.5-5 ms, 2-20 Hz, 5-15 V) evoked pulse duration- and frequency-dependent constriction of transverse and terminal arterioles. The vasoconstriction induced by low-frequency stimulation (2 Hz) was abolished by the alpha-adrenoceptor antagonist phentolamine, whereas high-frequency stimulation (10-20 Hz) resulted in a response that was only partially inhibited by phentolamine. However, desensitization of the tissue to the vasoconstrictor effects of neuropeptide Y (NPY) changed the response remaining after phentolamine into vasodilatation. Independent of stimulation parameters, pretreatment of the tissue with the adrenergic neuron blocker guanethidine reversed the constriction into dilatation that was resistant to propranolol, atropine, and indomethacin. The results document the functional presence of both vasoconstrictor and vasodilator fibers in the rabbit tenuissimus muscle motor nerve, and they suggest that part of the nerve-induced vasoconstriction at higher stimulation frequencies is caused by neuronally released NPY.

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Taste Responses of Neurons of the Hamster Solitary Nucleus Are Enhanced by Lateral Hypothalamic Stimulation

Journal of Neurophysiology ◽

10.1152/jn.00765.2001 ◽

2002 ◽

Vol 87 (4) ◽

pp. 1981-1992 ◽

Cited By ~ 41

Author(s):

Young K. Cho ◽

Cheng-Shu Li ◽

David V. Smith

Keyword(s):

Electrical Stimulation ◽

Brain Stem ◽

Taste Preference ◽

Gastric Distension ◽

Physiological Factors ◽

Homocysteic Acid ◽

Ipsilateral Stimulation ◽

Gustatory Information ◽

The Brain ◽

Stimulation Of

Gustatory responses in the brain stem are modifiable by several physiological factors, including blood insulin and glucose, intraduodenal lipids, gastric distension, and learning, although the neural substrates for these modulatory effects are not known. Stimulation of the lateral hypothalamus (LH) produces increases in food intake and alterations in taste preference behavior, whereas damage to this area has opposite effects. In the present study, we investigated the effects of LH stimulation on the neural activity of taste-responsive cells in the nucleus of the solitary tract (NST) of the hamster. Bipolar stimulating electrodes were bilaterally implanted in the LH, and the responses of 99 neurons in the NST, which were first characterized for their taste sensitivities, were tested for their response to both ipsilateral and contralateral LH stimulation. Half of the taste-responsive cells in the NST (49/99) were modulated by LH stimulation. Contralateral stimulation was more often effective (41 cells) than ipsilateral (13 cells) and always excitatory; 10 cells were excited bilaterally. Six cells were inhibited by ipsilateral stimulation. A subset of these cells ( n = 13) was examined for the effects of microinjection of dl-homocysteic acid (DLH), a glutamate receptor agonist, into the LH. The effects of electrical stimulation were completely mimicked by DLH, indicating that cell somata in and around the LH are responsible for these effects. Other cells ( n = 14) were tested for the effects of electrical stimulation of the LH on the responses to stimulation of the tongue with 0.032 M sucrose, NaCl, and quinine hydrochloride, and 0.0032 M citric acid. Responses to taste stimuli were more than doubled by the excitatory influence of the LH. These data show that the LH, in addition to its role in feeding and metabolism, exerts descending control over the processing of gustatory information through the brain stem.

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Joseph Lister: his contributions to early experimental physiology

Notes and Records the Royal Society journal of the history of science ◽

10.1098/rsnr.2013.0029 ◽

2013 ◽

Vol 67 (3) ◽

pp. 191-198 ◽

Cited By ~ 3

Author(s):

Edward R. Howard

Keyword(s):

Spinal Cord ◽

Experimental Science ◽

Spinal Cord Section ◽

Nervous Control ◽

Histological Studies ◽

University College London ◽

The Brain ◽

Contractile Tissue ◽

Needle Stimulation ◽

Stimulation Of

Joseph Lister (1827–1912) acquired a lifelong interest in histology and experimental physiology while a student at University College London between 1848 and 1852. His first two publications in 1853 were histological studies of the contractile tissue of the iris and the skin. Studies of inflammation in 1855 progressed to experiments on the nervous control of arteries, using techniques of peripheral nerve division, spinal cord section and needle stimulation of the brain. This interest in nervous mechanisms led to innovative experiments on gut motility and the autonomic nervous system, from which he inferred that sympathetic nerve control was mediated via intrinsic neuronal plexuses in the gut wall, a mode of action confirmed 100 years later, in 1964–65. It is not generally known that Lister was elected FRS for this early experimental work and that his early commitment to experimental science and microscopy was the background to his later work on the development of surgical antisepsis.

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Microinjection of codeine into the region of the caudal ventral respiratory column suppresses cough in anesthetized cats

Journal of Applied Physiology ◽

10.1152/japplphysiol.00783.2009 ◽

2010 ◽

Vol 108 (4) ◽

pp. 858-865 ◽

Cited By ~ 30

Author(s):

Ivan Poliacek ◽

Cheng Wang ◽

Lu Wen-Chi Corrie ◽

Melanie J. Rose ◽

Donald C. Bolser

Keyword(s):

Mechanical Stimulation ◽

Motor Response ◽

Esophageal Pressure ◽

Transversus Abdominis ◽

Homocysteic Acid ◽

Cough Reflex ◽

Posterior Cricoarytenoid ◽

Spontaneously Breathing ◽

The Brain ◽

Stimulation Of

We investigated the influence of microinjection of codeine into the caudal ventral respiratory column (cVRC) on the cough reflex. Experiments were performed on 36 anesthetized spontaneously breathing cats. Electromyograms (EMGs) were recorded bilaterally from inspiratory parasternal and expiratory transversus abdominis (ABD) muscles and unilaterally from laryngeal posterior cricoarytenoid and thyroarytenoid muscles. Repetitive coughing was elicited by mechanical stimulation of the intrathoracic airways. The unilateral microinjection of codeine (3.3 mM, 20–32 nl) in the cVRC reduced cough number by 29% ( P < 0.01) and expiratory cough amplitudes of esophageal pressure by 33% ( P < 0.05) as well as both ipsilateral and contralateral ABD EMGs by 35% and 48% ( P < 0.01 and P < 0.01, respectively). No cough depression was observed after microinjections of vehicle. There was no significant effect of microinjection of codeine in the cVRC (3.3 mM, 30–40 nl) on ABD activity induced by a microinjection of d,l-homocysteic acid (30 mM, 27–40 nl) in the same location. However, a cumulative dose of codeine (0.1 mg/kg, 330 nmol/kg) applied into the brain stem circulation through the vertebral artery reduced the ABD motor response to cVRC d,l-homocysteic acid microinjection (30 mM, 28–32 nl) by 47% ( P < 0.01). These results suggest that 1) codeine can act within the cVRC to suppress cough and 2) expiratory premotoneurons within the cVRC are relatively insensitive to this opioid.

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