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1.
J Sports Med Phys Fitness ; 55(11): 1285-92, 2015 Nov.
Article in English | MEDLINE | ID: mdl-25303166

ABSTRACT

AIM: The aim of this study was to investigate the short-term and long-term effects of a moderate intensity nordic walking program, and the feasibility of this exercise form among Hungarian community-living older adults. METHODS: Forty one community-living older adults aged over 60 years (mean 67.5, SD 4.8 years) participated in a nordic walking program consisting of a 10-week supervised period and a 25-week unsupervised period. The age and gender matched control group did not receive any types of exercise programs. The balance, functional mobility, lower limb strength, and aerobic endurance were measured at baseline, after 10 weeks and after 25 weeks. RESULTS: The balance, the functional mobility and the aerobic endurance significantly improved in the nordic walking group (P=0.001; P=0.04; P<0.0001, respectively), whereas there were significant deteriorations in the control group. In terms of lower limb muscle strenght (including iliopsoas, quadriceps, gluteus muscles, and hamstring muscles) we could not demonstrate improvement (P=0.274). CONCLUSION: This study showed that nordic walking is a simple, well-tolerated and effective physical activity for older people in Hungary. Based on the findings of our studies, the nordic walking will play an important role in geriatric physiotherapy in order to improve or maintain the functional abilities of this growing population.


Subject(s)
Muscle Strength/physiology , Physical Endurance/physiology , Postural Balance/physiology , Walking/physiology , Aged , Case-Control Studies , Feasibility Studies , Female , Follow-Up Studies , Humans , Independent Living , Leg/physiology , Longitudinal Studies , Male , Middle Aged , Muscle, Skeletal/physiology , Physical Fitness/physiology , Prospective Studies
2.
Neuroscience ; 124(4): 919-27, 2004.
Article in English | MEDLINE | ID: mdl-15026132

ABSTRACT

Evidence suggests that capsaicin-sensitive substance P (SP)-containing trigeminal ganglion neurons innervate the spiral modiolar artery (SMA), radiating arterioles, and the stria vascularis of the cochlea. Antidromic electrical or chemical stimulation of trigeminal sensory nerves results in neurogenic plasma extravasation in inner ear tissues. The primary aim of this study was to reveal the possible morphological basis of cochlear vascular changes mediated by capsaicin-sensitive sensory nerves. Therefore, the distribution of SP and capsaicin receptor (transient receptor potential vanilloid type 1-TRPV1) was investigated by double immunolabeling to demonstrate the anatomical relationships between the cochlear and vertebro-basilar blood vessels and the trigeminal sensory fiber system. Extensive TRPV1 and SP expression and co-localization were observed in axons within the adventitial layer of the basilar artery, the anterior inferior cerebellar artery, the SMA, and the radiating arterioles of the cochlea. There appears to be a functional relationship between the trigeminal ganglion and the cochlear blood vessels since electrical stimulation of the trigeminal ganglion induced significant plasma extravasation from the SMA and the radiating arterioles. The findings suggest that stimulation of paravascular afferent nerves may result in permeability changes in the basilar and cochlear vascular bed and may contribute to the mechanisms of vertebro-basilar type of headache through the release of SP and stimulation of TPVR1, respectively. We propose that vertigo, tinnitus, and hearing deficits associated with migraine may arise from perturbations of capsaicin-sensitive trigeminal sensory ganglion neurons projecting to the cochlea.


Subject(s)
Basilar Artery/innervation , Cochlea/blood supply , Neurons, Afferent/metabolism , Receptors, Drug/metabolism , Substance P/metabolism , Vertebral Artery/innervation , Animals , Arteries/innervation , Capillary Permeability , Electric Stimulation , Female , Fluorescent Antibody Technique , Guinea Pigs , Male , Nerve Fibers/metabolism , Tissue Distribution , Trigeminal Ganglion/physiology
3.
Hear Res ; 187(1-2): 1-11, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14698082

ABSTRACT

Tyrosine kinase receptors, including Trk A, Trk B and Trk C, participate in many different biological processes that are regulated by neurotrophic factors. Nerve growth factor (NGF)-triggered Trk A signaling is involved in growth, survival and differentiation of neurons in the central nervous system and in neural crest-derived cells. Trk A, Trk B and Trk C expression has been reported in the rat ventral cochlear nucleus. In the present study, we explored the immunocytochemical distribution of Trk A in the rodent inner ear. Rat and mouse cochleae were immunolabeled with a rabbit anti-Trk A polyclonal antibody (Chemicon) that has no reported cross-reactivity with Trk B and Trk C. In embryonic day 16 mice, no Trk A immunolabeling could be detected in the developing neuroepithelium. At postnatal day 6, weak Trk A labeling could be observed in both inner and outer hair cells. At postnatal day 12, enhanced punctate Trk A immunoexpression was present in hair cells. In adult mice and rats, intense Trk A labeling was observed in outer and inner hair cell bodies, in supporting cell bodies throughout the cochlea, and in spiral ganglion neurons. Trk A was not observed in stria vascularis, hair cell stereocilia, nor in the Trk B- and Trk C-rich cerebellum. This distribution pattern of Trk A suggests that its ligand, NGF, exerts significant trophic effects in the rodent inner ear.


Subject(s)
Ear, Inner/metabolism , Receptor, trkA/metabolism , Animals , Ear, Inner/cytology , Female , Hair Cells, Auditory, Inner/metabolism , Hair Cells, Auditory, Outer/metabolism , Humans , Immunohistochemistry , Male , Mice , Rats , Tissue Distribution
5.
Neuroscience ; 103(1): 189-201, 2001.
Article in English | MEDLINE | ID: mdl-11311800

ABSTRACT

Trigeminal neurogenic inflammation is one explanation for the development of vascular migraine. The triggers for this inflammation and pain are not well understood, but are probably vasoactive components acting on the blood vessel wall. Migraine-related inner ear symptoms like phonophobia, tinnitus, fluctuation in hearing perception and increased noise sensitivity provide indirect evidence that cochlear blood vessels are also affected by basilar artery migraine. The purpose of this investigation was to determine if a functional connection exists between the cochlea and the basilar artery. Neuronally mediated permeability changes in the cochlea and basilar artery were measured by colloidal silver and Evans Blue extravasation, following orthodromic and antidromic stimulation of the trigeminal ganglion innervating the cochlea. Capsaicin and electrical stimulation induced both dose- and time-dependent plasma extravasation of colloidal silver and Evans Blue from the basilar artery and anterior inferior cerebellar artery. Both orthodromic and antidromic activation of trigeminal sensory fibers also induced cochlear vascular permeability changes and significant quantitative differences between the treated and control groups in spectrophotometric assays. These results characterize a vasoactive connection between the cochlea and vertebro-basilar system through the trigeminal sensory neurons. We propose that vertigo, tinnitus and hearing deficits associated with basilar migraine could arise by excitation of the trigeminal nerve fibers in the cochlea, resulting in local plasma extravasation. In addition, cochlear "dysfunction" may also trigger basilar and cluster headache by afferent input to the trigeminal system.


Subject(s)
Basilar Artery/metabolism , Capsaicin/pharmacology , Cochlea/blood supply , Trigeminal Ganglion/physiology , Animals , Capillary Permeability , Cerebellum/blood supply , Cochlea/innervation , Coloring Agents , Electric Stimulation , Evans Blue , Female , Guinea Pigs , Male , Microscopy, Confocal , Silver Staining , Spectrophotometry , Vascular Headaches/etiology
6.
J Comp Neurol ; 419(3): 271-85, 2000 Apr 10.
Article in English | MEDLINE | ID: mdl-10723004

ABSTRACT

A neural connection between the trigeminal ganglion and the auditory brainstem was investigated by using retrograde and anterograde tract tracing methods: iontophoretic injections of biocytin or biotinylated dextran-amine (BDA) were made into the guinea pig trigeminal ganglion, and anterograde labeling was examined in the cochlear nucleus and superior olivary complex. Terminal labeling after biocytin and BDA injections into the ganglion was found to be most dense in the marginal cell area and secondarily in the magnocellular area of the ventral cochlear nucleus (VCN). Anterograde and retrograde labeling was also seen in the shell regions of the lateral superior olivary complex and in periolivary regions. The labeling was seen in the neuropil, on neuronal somata, and in regions surrounding blood vessels. Retrograde labeling was investigated using either wheatgerm agglutinin-horseradish peroxidase (WGA-HRP), BDA, or a fluorescent tracer, iontophoretically injected into the VCN. Cells filled by retrograde labeling were found in the ophthalmic and mandibular divisions of the trigeminal ganglion. We have previously shown that these divisions project to the cochlea and middle ear, respectively. This study provides the first evidence that the trigeminal ganglion innervates the cochlear nucleus and superior olivary complex. This projection from a predominantly somatosensory ganglion may be related to integration mechanisms involving the auditory end organ and its central targets.


Subject(s)
Auditory Pathways/physiology , Brain Stem/physiology , Trigeminal Ganglion/physiology , Animals , Brain Mapping , Cochlear Nucleus/physiology , Female , Guinea Pigs , Olivary Nucleus/physiology , Pregnancy , Trigeminal Nuclei/physiology
7.
J Clin Psychol ; 54(5): 611-9, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9696111

ABSTRACT

The study describes some interrelated patterns of traits of the House-Tree-Person (H-T-P) drawings with the instruments of hierarchical cluster analysis. First, according to the literature 1 7 formal or structural aspects of the projective drawings were collected, after which a detailed manual for coding was compiled. Second, the interrater reliability and the consistency of this manual was tested. Third, the hierarchical cluster structure of the reliable and consistent formal aspects was analysed. Results are: (a) a psychometrically tested coding manual of the investigated formal-structural aspects, each of them illustrated with drawings that showed the highest interrater agreement; and (b) the hierarchic cluster structure of the formal aspects of the H-T-P drawings of "normal" adults.


Subject(s)
Manuals as Topic/standards , Projective Techniques , Psychometrics/methods , Psychomotor Performance/classification , Adolescent , Adult , Cluster Analysis , Creativity , Female , Humans , Male , Middle Aged , Observer Variation , Projective Techniques/standards , Psychometrics/standards , Reference Values , Reproducibility of Results
8.
Exp Neurol ; 151(2): 241-8, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9628760

ABSTRACT

This paper reports that endolymphatic hydrops causes a significant reduction of retrogradely labeled cell bodies of the ipsilateral trigeminal ganglion following application of horseradish peroxidase in the cochlea. We previously showed that the trigeminal ganglion is a source of primary sensory innervation to the cochlear blood vessels. The innervation of the cochlea from the trigeminal ganglion may provide the basis of an alternative mechanism for Ménière's syndrome (imbalance, hearing loss, tinnitus, and a sensation of fullness in the ear) for which a central neural basis has been speculated. Innervation patterns of sensory nerves from the trigeminal ganglion to the cochlear blood vessels were studied using retrograde transport of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP). Healthy and hydropic guinea pigs were unilaterally implanted with an osmotic pump and a cannula for cochlear delivery of 2% WGA-HRP or vehicle alone. In other guinea pigs the cochlea was pretreated with 100 micromol capsaicin before administering 2% WGA-HRP. Histological sections of the ipsi- and contralateral trigeminal ganglia were obtained 48 h after WGA-HRP infusion. In the hydropic guinea pig, the number of labeled nerve cell bodies observed in the anteriomedial portion of the trigeminal ganglion at the origin of the ophthalmic nerve was reduced by 70% relative to normal animals. Capsaicin pretreatment nearly eliminated the labeled sensory fibers as expected. These data indicate that the trigeminal innervation to the cochlea could be involved in inner ear homeostatic disturbances, including the hydrops that is symptomatic of Ménière's disease.


Subject(s)
Cochlea/physiopathology , Endolymphatic Hydrops/physiopathology , Trigeminal Nerve/physiopathology , Animals , Axonal Transport/physiology , Capsaicin/pharmacology , Female , Guinea Pigs , Male , Neurons, Afferent/chemistry , Neurons, Afferent/physiology , Receptors, Drug/agonists , Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate
9.
Neuroscience ; 84(2): 559-67, 1998 May.
Article in English | MEDLINE | ID: mdl-9539226

ABSTRACT

This paper provides the first detailed description of the trigeminal innervation of the inner ear vasculature. This system provides a newly discovered neural substrate for rapid vasodilatatory responses of the inner ear to high levels of activity and sensory input. Moreover, this discovery may provide an alternative mechanism for a set of clinical disturbances (imbalance, hearing loss, tinnitus and headache) for which a central neural basis has been speculated. Iontophoretic injections of biocytin were made via a glass microelectrode into the trigeminal ganglion in guinea-pigs. Tissue for histological sections was obtained 24 h later. Labeled fibers from the injection site were observed as bundles around the ipsilateral spiral modiolar blood vessels, as individual labeled fibers in the interscala septae, and in the ipsilateral stria vascularis. The dark cell region of the cristae ampullaris in the vestibular labyrinth was also intensively labeled. No labeled fibers were observed in the neuroepithelium of the cristae ampullaris or the semicircular canals. These results confirm and localize an earlier indirect observation of the trigeminal ganglion projection to the cochlea. This innervation may play a role in normal vascular tone and in some inner ear disturbances, e.g., sudden hearing loss may reflect an abnormal activity of trigeminal ganglion projections to the cochlear blood vessels.


Subject(s)
Blood Vessels/innervation , Cochlea/blood supply , Neurons/physiology , Trigeminal Ganglion/physiology , Trigeminal Nerve/physiology , Animals , Axonal Transport , Axons/physiology , Axons/ultrastructure , Basilar Artery/anatomy & histology , Basilar Artery/innervation , Blood Vessels/anatomy & histology , Cerebral Arteries/anatomy & histology , Cerebral Arteries/innervation , Functional Laterality , Guinea Pigs , Horseradish Peroxidase , Isoquinolines , Lysine/analogs & derivatives , Nerve Fibers/physiology , Nerve Fibers/ultrastructure , Neurons/cytology , Neurons/ultrastructure , Trigeminal Ganglion/anatomy & histology , Trigeminal Ganglion/cytology , Trigeminal Nerve/anatomy & histology , Trigeminal Nerve/cytology , Vasodilation
10.
Neuroscience ; 79(2): 605-15, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9200743

ABSTRACT

Innervation patterns of sensory nerves from the trigeminal ganglion to the cochlear blood vessels were studied using retrograde transport of wheat germ agglutinin conjugated to horseradish peroxidase. Guinea-pigs (n=7) were unilaterally implanted with an osmotic pump and a cannula for cochlear delivery of 2% or 20% wheat germ agglutinin horseradish peroxidase (Group 1), 2% wheat germ agglutinin-horseradish peroxidase followed by 100 micromol capsaicin (Group 2), or vehicle alone. Histological sections of the trigeminal ganglia, the C1 and C2 dorsal ganglia, the superior and inferior ganglia of the glossopharyngeal nerve bilaterally, the midbrain and the brainstem were obtained after 48 h of infusion. In Group 1, a large number of labeled nerve cell bodies were observed in the anteromedial portion of the trigeminal ganglion and at the origin of the ophthalmic nerve. Some labeled cells were also found on the lateral side of the ophthalmic nerve, as well as on the medial side of the maxillary nerve root. Capsaicin pretreatment significantly reduced the density of labeled neurons in the trigeminal ganglion. A few labeled neurons were also found in the trigeminal brainstem nucleus complex and in certain auditory brainstem nuclei. No wheat germ agglutinin horseradish peroxidase-positive cells were observed in the spinal C1 or C2 cervical ganglia or in the superior or inferior glossopharyngeal ganglia. In contrast, wheat germ agglutinin-horseradish peroxidase application to the middle ear resulted in labeled cells in the middle posterolateral portion of the trigeminal ganglia and in the superior ganglia of the glossopharyngeal nerve. These results provide the first direct evidence that the trigeminal ganglion sends projections to the cochlea.


Subject(s)
Cochlea/anatomy & histology , Trigeminal Ganglion/anatomy & histology , Animals , Female , Guinea Pigs , Histocytochemistry , Male , Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate
11.
Hear Res ; 100(1-2): 114-9, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8922985

ABSTRACT

Capsaicin has been previously shown to increase cochlear blood flow (CBF) in a dose-dependent manner. The aim of this study was to define the role of nitric oxide (NO) in capsaicin-induced changes in CBF. This was investigated in the anesthetized guinea pig, utilizing laser Doppler flowmetry. Application of capsaicin (64.8 and 6.48 nmol in 2 microliters of saline) to the round window membrane (RWM) caused increases in CBF (34 +/- 2.8% of baseline (BL) and 28 +/- 2.3% BL, respectively (P < 0.001)). Application of the NO synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME) (10 mg/kg intravenously or topically to the RWM) reduced blood flow in the cochlea, as previously reported. After pretreatment with i.v. L-NAME, the effect of capsaicin on CBF was significantly decreased. With the dose of capsaicin at 64.8 nmol, the increase in CBF fell from 34 +/- 2.8% BL to 6.9 +/- 1.5% BL (P < 0.001), and at 6.48 nmol it fell from 28 +/- 2.3% BL to 4.8 +/- 1.6% BL (P < 0.001). RWM L-NAME application also decreased the capsaicin vasodilatation effect. A capsaicin dose of 64.8 nmol resulted in only a 10 +/- 2.5% BL increase in CBF, and with 6.48 nmol capsaicin the increase was 7.8 +/- 2.2% of BL (P < 0.001). Capsaicin-sensitive sensory neurons in other systems are generally known to release substance P (SP), which in turn elicits release of endothelium derived relaxing factor (NO). The results of this study indicate that NO is a mediator of capsaicin-sensitive sensory neuronal function in CBF regulation.


Subject(s)
Capsaicin/toxicity , Cochlea/blood supply , NG-Nitroarginine Methyl Ester/toxicity , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide/metabolism , Animals , Cochlea/drug effects , Dose-Response Relationship, Drug , Drug Interactions , Female , Guinea Pigs , Injections, Intravenous , Laser-Doppler Flowmetry , Male , NG-Nitroarginine Methyl Ester/administration & dosage , Neurons, Afferent/cytology , Neurons, Afferent/metabolism , Nitric Oxide/physiology , Substance P/metabolism
12.
Arch Oral Biol ; 41(7): 699-704, 1996 Jul.
Article in English | MEDLINE | ID: mdl-9015572

ABSTRACT

The aim was to examine whether (1) blood flow and vascular resistance are altered in response to exogenous nitric oxide and (2) whether endogenous synthesis of nitric oxide participates in the haemodynamic regulation of the submandibular, parotid and pancreatic glands. Experiments were performed on anaesthetized, artificially ventilated cats. Mean arterial blood pressure, heart rate, blood gases, cardiac output and tissue blood flow were determined before and 15 min after intravenous administration of either the nitric oxide donor SIN-1 (3-morpholinosydnonimine, 1 mg/kg, n = 10) or the competitive nitric oxide synthase inhibitor NOLA (NG-nitro-L-arginine, 30 mg/kg, n = 9) blood flow was measured by a radioactive-labelled microsphere method. In the SIN-1 group, in spite of a serious decrease in mean arterial blood pressure (p < 0.001), the blood flow in the glands remained unchanged. The vascular resistance decreased after SIN-1 in the submandibular and pancreatic glands (p < 0.001 and p < 0.05, respectively), and was slightly reduced in the parotid. The NOLA increased mean arterial blood pressure (p < 0.01) and reduced the blood flow in the submandibular and pancreatic glands (p < 0.01 and p < 0.001, respectively), but the decrease in the parotid was not significant. Vascular resistance increased after NOLA in all three glands (p < 0.05, p < 0.001 and p < 0.05). These findings suggest that basal nitric oxide production in these exocrine glands is sufficient to modulate vascular resistance. Moreover, the release of endogenous NO from the nerves and/or endothelium is probably involved in the regulation of vascular tone. The nitric oxide-dependent component of blood-flow regulation, however, seems to be less pronounced in the parotid gland.


Subject(s)
Exocrine Glands/blood supply , Hemodynamics/drug effects , Nitric Oxide Synthase/metabolism , Nitric Oxide/physiology , Animals , Blood Flow Velocity/drug effects , Blood Pressure/drug effects , Cats , Endothelium, Vascular/enzymology , Endothelium, Vascular/innervation , Enzyme Inhibitors/pharmacology , Exocrine Glands/enzymology , Male , Molsidomine/analogs & derivatives , Molsidomine/pharmacology , Nerve Fibers/metabolism , Nitric Oxide/biosynthesis , Nitric Oxide/pharmacology , Nitric Oxide Synthase/analysis , Nitric Oxide Synthase/antagonists & inhibitors , Nitroarginine/pharmacology , Pancreas/blood supply , Pancreas/enzymology , Parotid Gland/blood supply , Parotid Gland/enzymology , Regional Blood Flow/drug effects , Submandibular Gland/blood supply , Submandibular Gland/enzymology , Vascular Resistance/drug effects , Vasodilator Agents/pharmacology
13.
Transpl Int ; 9 Suppl 1: S68-72, 1996.
Article in English | MEDLINE | ID: mdl-8959794

ABSTRACT

The measurement of enzyme activity in urine provides a sensitive assessment for renal tubular cell damage. The present study was undertaken to evaluate the clinical value of the determination of tubular brush-border-associated enzymes, alkaline phosphatase (AP), gamma-glutamyl transferase (GGT), leucine aminopeptidase (LAP), and dipeptidyl peptidase IV (DPP), of patients with normal graft function (NOR, n = 20), with acute tubular necrosis (ATN, n = 11), with an acute rejection episode (ARE, n = 17) after transplantation, and of healthy persons (n = 20). The second urine of the morning was collected daily during the patients' stay in hospital. The enzyme activities were measured at 25 degrees C and were expressed as U/mmol creatinine. The enzymuria in NOR is higher than in healthy controls, but is still in the normal range. By 5 days after transplantation the initial increased excretion declines as the graft function improves. Elevated enzymuria (DPP 0.69 +/- 0.56, AP 3.06 +/- 3.24, GGT 4.16 +/- 4.13, and LAP 1.39 +/- 1.27) was observed during the rejection episodes. Two days before clinical diagnosis of rejection, the release of DPP-IV and GGT increases to double, and the AP and LAP increases to 3 times the value on the fourth day before rejection. Successful treatment of rejection coincided with a quick return by the third day of the rejection period to the previous enzyme distribution. In ATN no decrease of enzymuria occurs and the excretion is much higher than in ARE. Our method with the every day monitoring of kidney graft function offers the possibility for the early diagnosis of acute rejection.


Subject(s)
Clinical Enzyme Tests , Kidney Transplantation , Adult , Alkaline Phosphatase/analysis , Dipeptidyl Peptidase 4/analysis , Female , Humans , Kidney Tubular Necrosis, Acute/diagnosis , Leucyl Aminopeptidase/analysis , Male , gamma-Glutamyltransferase/analysis
14.
Acta Otolaryngol ; 115(6): 754-8, 1995 Nov.
Article in English | MEDLINE | ID: mdl-8749196

ABSTRACT

Capsaicin, which causes release of neuropeptides including substance P, has been shown to cause dose-related increases in cochlear blood flow (CBF). Since CBF regulation is altered in animal models with endolymphatic hydrops, this study was designed to examine the effect of hydrops on capsaicin-induced CBF changes. CBF responses to 0.01 and 0.001% capsaicin applied to the round window membrane were measured in normal and 12-week hydropic guinea pigs using laser Doppler flowmetry. With 0.01% capsaicin, CBF increased by only 13 +/- 7.8% in the hydropic ear, compared with 34% +/- 13% in the normal animal (p = 0.027). With 0.001% capsaicin, CBF increased by only 7.5 +/- 4.2% in the hydropic ear, compared with 28 +/- 16% in the normal ear (p < 0.001). These findings demonstrate a reduced responsiveness to capsaicin with endolymphatic hydrops and suggest that hydrops causes an alteration in the peptidergic sensory fibers of the inner ear or in the vascular smooth muscle or both. The results are consistent with previous reports of reduced vascular responsiveness in hydropic guinea pigs and provide further evidence for abnormal CBF regulation in hydrops.


Subject(s)
Alkaloids/pharmacology , Capsaicin/pharmacology , Cochlea/blood supply , Cochlea/drug effects , Endolymphatic Hydrops/physiopathology , Animals , Cochlea/physiopathology , Female , Guinea Pigs , Laser-Doppler Flowmetry , Male
15.
Hear Res ; 89(1-2): 86-92, 1995 Sep.
Article in English | MEDLINE | ID: mdl-8600135

ABSTRACT

Physiological evidence from several studies suggests that endogenous vasoactive peptides, such as substance P (SP), and their respective receptor populations may participate in the mechanisms that govern the autoregulatory capacity of the cochlear vascular system. However, these studies do not provide evidence regarding the origin or mechanism of action of SP. Capsaicin sensitivity has been used as a marker for sensory neurons, and the release of SP following capsaicin treatment suggests a sensory transmitter role for SP. The present investigation examines the relationship between the capsaicin-sensitive sensory neurons and SP in the regulation of cochlear blood flow (CBF). In 75 pigmented guinea pigs, the cochlea was surgically exposed and a laser Doppler flowmeter probe placed on the bony surface of the first turn to monitor CBF. Capsaicin solutions (2 microliters, 0.01%, 0.001% and 0.0001%) applied to the round-window membrane (RWM) resulted in a dose-related CBF increase, without change in the systemic blood pressure. This effect could be inhibited by application of a specific SP receptor antagonist, [D-Pro2,D-Trp7,9]-SP, after which none of the capsaicin concentrations used induced a change in CBF. Moreover, after RWM application of 50 nmol/2 microliters of SP there was a significant increase in CBF. No CBF change was observed with the lower concentrations of 10 nmol SP or 100 pmol SP. These results indicate a role of SP in CBF regulation and give indirect evidence that SP is released from capsaicin-sensitive primary sensory neurons.


Subject(s)
Capsaicin/pharmacology , Cochlea/blood supply , Cochlea/drug effects , Substance P/metabolism , Animals , Blood Flow Velocity/drug effects , Blood Flow Velocity/physiology , Cochlea/innervation , Female , Guinea Pigs , Homeostasis , Male , Neurons, Afferent/drug effects , Neurons, Afferent/physiology , Substance P/analogs & derivatives , Substance P/antagonists & inhibitors , Substance P/pharmacology , Substance P/physiology
16.
J Dent Res ; 74(8): 1501-6, 1995 Aug.
Article in English | MEDLINE | ID: mdl-7560406

ABSTRACT

Many authors have studied the hemodynamics of the dental pulp; however, there are scarcely any data regarding the involvement of the L-arginine/nitric oxide pathway in the regulatory mechanism. Thus, we have examined the physiological effects of (1) NG-nitro-L-arginine as an inhibitor of nitric oxide synthesis and (2) the nitric oxide donor 3-morpholinosydnonimine on blood flow and vascular resistance in the canines of anesthetized cats to study the potential involvement of nitric oxide in the regulation of dental vascular homeostasis. Mean arterial blood pressure, heart rate, blood gases, pH, cardiac output, and tissue blood flow were determined prior to and 15 min after i.v. administration of either NG-nitro-L-arginine (30 mg/kg, n = 9) or 3-morpholinosydnonimine (1 mg/kg, n = 7). Blood flow was measured by radioactive-labeled microspheres. There were no significant differences in baseline parameters between the two groups of cats. The dental pulp blood flow decreased to 53 +/- 13% (p < 0.01) of the control level after NG-nitro-L-arginine administration, while it decreased only slightly (to 82 +/- 12%) after 3-morpholinosydnonimine administration. The dental pulp's vascular resistance increased to 367 +/- 69% (p < 0.01) of the control level after NG-nitro-L-arginine, while it decreased to 73 +/- 10% (p < 0.05) of control after 3-morpholinosydnonimine. We found that the L-arginine/nitric oxide pathway plays an important role in the regulation of pulpal blood circulation.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Dental Pulp/blood supply , Nitric Oxide/physiology , Animals , Arginine/analogs & derivatives , Arginine/pharmacology , Arginine/physiology , Blood Pressure/drug effects , Cardiac Output/drug effects , Cats , Cuspid , Enzyme Inhibitors/pharmacology , Heart Rate/drug effects , Homeostasis , Male , Molsidomine/analogs & derivatives , Molsidomine/pharmacology , NG-Nitroarginine Methyl Ester , Nitric Oxide/antagonists & inhibitors , Nitric Oxide Synthase/antagonists & inhibitors , Oxygen/blood , Regional Blood Flow , Vascular Resistance/drug effects , Vasodilator Agents/pharmacology
17.
Acta Otolaryngol ; 114(2): 156-61, 1994 Mar.
Article in English | MEDLINE | ID: mdl-8203197

ABSTRACT

Capsaicin-induced microcirculatory changes in the cochlea of anaesthetized guinea pigs were examined by laser-Doppler flowmetry. Close intraarterial capsaicin infusion into the anterior inferior cerebral artery at doses of 10-50 pmol/min was followed by dose-dependent vasodilatation. Capsaicin infused in a dose of 150-200 pmol/min or above resulted in vasoconstriction in the region examined. Topical capsaicin administration into the cochlea (50-150 pmol) resulted in very moderate vasodilation with a latency of 1-2 min. Perivascular capsaicin application onto the anterior inferior cerebellar artery elicited an elevated blood flow in the cochlea, too. It is concluded that the release of vasoactive substances from capsaicin-sensitive nerve fibres in the inner ear of the guinea pig may play a role in the control of the local microcirculation. These nerves may also be involved in the neurogenic inflammatory processes in the region.


Subject(s)
Capsaicin/pharmacology , Cochlea/blood supply , Cochlea/innervation , Nerve Fibers/drug effects , Nerve Fibers/physiology , Neurons, Afferent/drug effects , Neurons, Afferent/physiology , Animals , Arteries/drug effects , Basilar Artery , Blood Pressure/drug effects , Blood Pressure/physiology , Capsaicin/administration & dosage , Cerebellum/blood supply , Cochlea/drug effects , Dose-Response Relationship, Drug , Guinea Pigs , Heart Rate/drug effects , Heart Rate/physiology , Infusions, Intra-Arterial , Laser-Doppler Flowmetry , Microcirculation/drug effects , Microcirculation/physiology , Microinjections , Pilot Projects , Regional Blood Flow/drug effects , Regional Blood Flow/physiology , Time Factors , Vasoconstriction , Vasodilation
18.
Fogorv Sz ; 86(5): 171-5, 1993 May.
Article in Hungarian | MEDLINE | ID: mdl-8243735

ABSTRACT

The studies were focused on the corrosion stability of dental alloys (containing NiCr and stainless steel), for a possible release of Nickel (Ni). The investigations were carried out in artificial saliva at 37 degrees C. The potential range, where Ni dissolution may occur, was determined by transient measurements. It has been established, that: 1. Under in vivo conditions the probability of the pitting corrosion is very low. 2. The Ni release takes place on the temporarily damaged, locally activated parts of the surfaces.


Subject(s)
Chromium , Dental Alloys , Nickel , Stainless Steel , Corrosion , Electrochemistry , Humans , In Vitro Techniques , Saliva , Solubility , Temperature
19.
Eur Arch Otorhinolaryngol ; 250(2): 101-4, 1993.
Article in English | MEDLINE | ID: mdl-8507463

ABSTRACT

To determine the relationship between the dynamics of mean arterial blood pressure (MABP) elevation and possible changes in the cochlear microcirculation the cochlear blood flow (CBF) was measured in guinea pigs by a laser Doppler method. The MABP was elevated at rates ranging from 0.02 mmHg/s to 4 mmHg/s by intravenous infusions of norepinephrine or epinephrine in various concentrations. A fall in MABP was induced by exsanguination of the animals. The purpose of the experiments was to record the time of onset and course of an expected autoregulation in the cochlea in response to slow or rapid changes in MABP. The data suggest that there is no short-term autoregulation in the cochlear microcirculation reflecting the increase of the MABP, but a slight compensation occurs when the MABP declines. These latter changes could be attributed to the high CO2 sensitivity of the cochlear blood vessels.


Subject(s)
Blood Flow Velocity , Blood Pressure/physiology , Cochlea/blood supply , Homeostasis/physiology , Microcirculation/physiology , Animals , Blood Pressure/drug effects , Carbon Dioxide , Cerebrovascular Circulation/physiology , Epinephrine/pharmacology , Guinea Pigs , Homeostasis/drug effects , Laser-Doppler Flowmetry , Microcirculation/drug effects , Norepinephrine/pharmacology , Regional Blood Flow/physiology , Regression Analysis , Vasomotor System/physiology
20.
Fogorv Sz ; 86(1): 9-14, 1993 Jan.
Article in Hungarian | MEDLINE | ID: mdl-8472839

ABSTRACT

The authors describe a computer analysable etiological card used for registration of data of Ni hypersensitive patients' with oral symptoms. The collection and evaluation of the data related to the pathological changes and predisposing factors can be useful in prevention of development of hypersensitivity or clinical symptoms of hypersensitivity in cases belonging to this risk group.


Subject(s)
Dental Materials/adverse effects , Dental Records , Drug Hypersensitivity/etiology , Medical Records Systems, Computerized , Metals/adverse effects , Drug Hypersensitivity/immunology , Hungary , Metals/immunology
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