Editorial Comment to Spinal glycinergic and gamma‐aminobutyric acid‐ergic neurons inhibit the micturition reflex after electrical stimulation of the perineum in rats with pelvic venous congestion

2019 ◽  
Vol 26 (12) ◽  
pp. 1156-1156
Author(s):  
Motoaki Saito
Keyword(s):  
Electrical Stimulation ◽  
Editorial Comment ◽  
Venous Congestion ◽  
Aminobutyric Acid ◽  
Gamma Aminobutyric Acid ◽  
Micturition Reflex ◽  
Stimulation Of

A model of dynamic exercise: the decerebrate rat locomotor preparation

1992 ◽  
Vol 72 (1) ◽  
pp. 121-127 ◽  
Author(s):  
T. G. Bedford ◽  
P. K. Loi ◽  
C. C. Crandall
Keyword(s):  
Blood Pressure ◽  
Electrical Stimulation ◽  
Blood Pressure Response ◽  
Pressor Response ◽  
Dynamic Exercise ◽  
Pressure Response ◽  
Aminobutyric Acid ◽  
Gamma Aminobutyric Acid ◽  
Decerebrate Rat ◽  
Stimulation Of

The purpose of this study was to develop a dynamic exercise model in the rat that could be used to study central nervous system control of the cardiovascular system. Rats of both sexes were decerebrated under halothane anesthesia and prepared for induced locomotion on a freely turning wheel. Electrical stimulation of the mesencephalic locomotor region (MLR) elicited locomotion at different speeds and gait patterns and increased heart rate and blood pressure. Two maneuvers were performed to illustrate the potential use of the preparation. The first maneuver consisted of muscular paralysis, which prevents excitation of muscle mechanoreceptors and chemoreceptors resulting from exercise. MLR stimulation still increased blood pressure. The second maneuver was performed to determine whether the blood pressure response obtained during paralysis was an artifact of electrical stimulation of the MLR. After microinjection of gamma-aminobutyric acid into the MLR, electrical current thresholds for blood pressure and locomotion increased in parallel. gamma-Aminobutyric acid injection also reduced the pressor response to suprathreshold electrical stimulation by 76%. The injection results suggest that electrical stimulation of the MLR activates cells rather than fibers of passage. The blood pressure response of the exercise model is probably not an artifact of stimulation. The decerebrate rat locomotor preparation should offer another approach to investigate difficult problems in exercise physiology.

Putative mechanisms involved in excitatory and inhibitory effects of somatostatin on intestinal motility

1989 ◽  
Vol 257 (4) ◽  
pp. G532-G538 ◽  
Author(s):  
T. Takeda ◽  
K. Taniyama ◽  
S. Baba ◽  
C. Tanaka
Keyword(s):  
Electrical Stimulation ◽  
Longitudinal Muscle ◽  
Cholinergic Neuron ◽  
Gamma Aminobutyric Acid ◽  
Inhibitory Effects ◽  
Guinea Pig Ileum ◽  
Excitatory Effect ◽  
Ergic Neuron ◽  
Gabaa Antagonist ◽  
Stimulation Of

The mechanism of action of somatostatin on the motility of intestine was examined in the entire preparation and the longitudinal muscle attached with Auerbach's plexus (LA) preparation of guinea pig ileum, in relation to the cholinergic neuron and gamma-aminobutyric acid (GABA)ergic neuron. Somatostatin produced a transient potentiation of electrical stimulation-induced twitch contractions followed by an inhibition. The excitatory effect of somatostatin was associated with an increase in the release of [3H]acetylcholine (ACh) from the preparations preloaded with [3H]choline. Bicuculline, a GABAA antagonist, inhibited the somatostatin-induced excitatory effect. Somatostatin inhibited the electrical stimulation-induced twitch contraction and release of [3H]ACh, and the inhibition was greater in the entire preparation than in the LA. Phaclofen, a GABAB antagonist, prevented the inhibitory effects of somatostatin. Somatostatin induced a Ca2+ -dependent, tetrodotoxin-sensitive release of [3H]GABA from the preparations preloaded with [3H]GABA. Therefore somatostatin exerts excitatory and inhibitory effects on the cholinergic neuron due to the stimulation of the GABAergic neuron, and the motility of the intestine is regulated.

Effects of WAY100635, a selective 5-HT1A-receptor antagonist on the micturition-reflex pathway in the rat

2001 ◽  
Vol 280 (5) ◽  
pp. R1407-R1413 ◽  
Author(s):  
Hidehiro Kakizaki ◽  
Mitsuharu Yoshiyama ◽  
Tomohiko Koyanagi ◽  
William C. De Groat
Keyword(s):  
Spinal Cord ◽  
Electrical Stimulation ◽  
Receptor Antagonist ◽  
Intrathecal Injection ◽  
Cervical Cord ◽  
Dependent Manner ◽  
Reflex Pathway ◽  
Micturition Reflex ◽  
Female Wistar Rats ◽  
Stimulation Of

5-Hydroxytryptamine (5-HT) receptors in the central nervous system have been implicated in the control of micturition. The present study was undertaken to evaluate the effects of a selective 5-HT1A-receptor antagonist { N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]- N-(2-pyridinyl)cyclohexanecarboxamide trihydrochloride (WAY100635)} on the micturition-reflex pathway in urethane-anesthetized female Wistar rats. Rhythmic isovolumetric bladder contractions evoked by bladder distension were abolished by 0.3- to 3-mg/kg iv or 30- to 100-μg intrathecal (it) administration of WAY100635 in a dose-dependent manner for periods of 3–15 min. Intrathecal injection of WAY100635 was effective only if injected at the L6-S1 spinal cord level, but not at the thoracic or cervical cord levels. WAY100635 (30–100 μg it) significantly reduced the amplitude of bladder contractions evoked by electrical stimulation of the pontine micturition center. However, the field potentials in the rostral pons evoked by electrical stimulation of pelvic nerve were not affected by intrathecal or intravenous injection of WAY100635. These results suggest that 5-HT1A receptors at the L6-S1 level of the spinal cord have an important role in the tonic control of the descending limb of the micturition-reflex pathway in the rat.

Neurons of C1 area mediate cardiovascular responses initiated from ventral medullary surface

1986 ◽  
Vol 250 (5) ◽  
pp. R932-R945 ◽  
Author(s):  
E. E. Benarroch ◽  
A. R. Granata ◽  
D. A. Ruggiero ◽  
D. H. Park ◽  
D. J. Reis
Keyword(s):  
Heart Rate ◽  
Electrical Stimulation ◽  
Arterial Pressure ◽  
Cardiovascular Responses ◽  
Ventral Surface ◽  
Aminobutyric Acid ◽  
Ventrolateral Medulla ◽  
Gamma Aminobutyric Acid ◽  
Pressor Responses ◽  
Ventral Medullary Surface

We sought to establish whether neurons of the C1 area of the rostral ventrolateral medulla (RVL) mediate changes in arterial pressure and heart rate evoked by topical application of drugs to the ventral medullary surface of the rat. Animals were anesthetized, paralyzed, and ventilated. The ventral surface was mapped with L-glutamate, and a restricted zone was identified from which L-glutamate, as well as kainic acid, bicuculline, strychnine, carbachol, or physostigmine, increased arterial pressure and heart rate. The hypertensive effects of carbachol and physostigmine were blocked by previous local application of atropine but not hexamethonium. Application of gamma-aminobutyric acid (GABA) or glycine to this area produced hypotension and bradycardia. Located caudal to the trapezoid bodies and lateral to the pyramids, this area corresponded to points with lowest threshold for pressor responses evoked by electrical stimulation and overlapped the distribution of epinephrine-synthesizing cells of the RVL. Processes arising from these neurons were identified reaching and contacting the ventral surface. Unilateral lesions involving the C1 area or phenylethanolamine-N-methyltransferase-labeled descending axons derived from this area imparied by greater than 70% the response to ipsilateral application of L-glutamate, GABA, or glycine to the ventral surface. We suggest that neurons within the C1 area of RVL adjacent to or including epinephrine cells may mediate cardiovascular changes elicited from a restricted chemosensitive zone of the ventral medullary surface of the rat.

Effects of groups of propriospinal interneurons on fictive swimming in the isolated spinal cord of the lamprey

1985 ◽  
Vol 54 (4) ◽  
pp. 959-977 ◽  
Author(s):  
C. M. Rovainen
Keyword(s):  
Spinal Cord ◽  
Electrical Stimulation ◽  
Excitatory Amino Acid ◽  
Extracellular Recording ◽  
Phase Lag ◽  
Gamma Aminobutyric Acid ◽  
Ventral Roots ◽  
Pattern Generators ◽  
Caudal Spinal Cord ◽  
Stimulation Of

Fictive swimming activity was induced in isolated spinal cords of adult lampreys Ichthyomyzon unicuspis and Petromyzon marinus by addition of D-glutamate or N-methyl-D,L-aspartate (NMA) to the bathing fluid. Propriospinal interneurons are defined as nerve cells within the spinal cord with projections longer than 1 segment. The hypothesis that propriospinal interneurons contribute to intersegmental coordination during fictive swimming was tested using electrical stimulation, extracellular recording, and separated compartments. Stimulation of the split caudal end of the spinal cord indirectly excited ascending propriospinal interneurons, which enhanced and entrained bursts in rostral contralateral ventral roots. Indirect electrical stimulation of descending propriospinal interneurons could delay and diminish bursts in caudal contralateral ventral roots. Extracellular recordings from the rostral and caudal split ends of the spinal cord sometimes showed spike activities in phase with contralateral or ipsilateral ventral roots. Inhibition of 1-3 segments by spot applications of glycine or gamma-aminobutyric acid (GABA) did not interrupt normal coordination or rostrocaudal phase lag. When a middle region of spinal cord was inhibited in a compartment with GABA or glycine, the caudal spinal cord could entrain the bursts in rostral ventral roots. In a few preparations the caudal region induced antiphasic bursts in previously silent rostral roots through the inhibited region. The maximum separation for caudal-upon-rostral antiphasic entrainment was approximately 20 segments in Ichthyomyzon and 36 segments in Petromyzon. Increased concentrations of an excitatory amino acid in a rostral compartment could produce descending entrainment of bursts in an adjacent caudal compartment at a higher frequency with rostrocaudal phase lag. The rostral-upon-caudal entrainment could still occur through spot applications of GABA or glycine but not through long inhibited regions. Two hypothetical groups of propriospinal interneurons are proposed for the coordination of swimming activities in the isolated spinal cords of adult lampreys. 1) Crossed, ascending interneurons may be excited in phase with nearby motoneurons and may excite and entrain rostral pattern generators on the opposite side. 2) Short, commissural interneurons may be excited in phase with nearby motoneurons and may inhibit contralateral generators.

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