scholarly journals Involvement of spinal α2-adrenoceptors in prolonged modulation of hind limb withdrawal reflexes following acute noxious stimulation in the anaesthetized rabbit

2016 ◽  
Vol 43 (6) ◽  
pp. 834-845 ◽  
Author(s):  
John Harris
Keyword(s):  
Hind Limb ◽  
Noxious Stimulation ◽  
Α2 Adrenoceptors ◽  
Anaesthetized Rabbit ◽  
Withdrawal Reflexes

Peri-MAC Depression of a Nociceptive Withdrawal Reflex Is Accompanied by Reduced Dorsal Horn Activity with Halothane but not Isoflurane

2003 ◽  
Vol 98 (5) ◽  
pp. 1128-1138 ◽  
Author(s):  
Steven L. Jinks ◽  
John T. Martin ◽  
Earl Carstens ◽  
Sung-Won Jung ◽  
Joseph F. Antognini
Keyword(s):  
Spinal Cord ◽  
Dorsal Horn ◽  
Hind Limb ◽  
Mechanical Stimulus ◽  
General Anesthetics ◽  
Neuronal Responses ◽  
Stimulus Response ◽  
Dorsal Horn Neurons ◽  
Force Reduction ◽  
Withdrawal Reflexes

Background Anesthetics act in the spinal cord to suppress movement evoked by a noxious stimulus, although the exact site is unknown. Methods This study investigated sensorimotor processing in hind limb withdrawal reflexes, and effects of two general anesthetics, halothane and isoflurane, on simultaneously recorded responses of single dorsal horn neurons and hind limb withdrawal force, elicited by graded noxious thermal hind paw stimulation in rats. Minimum alveolar anesthetic concentration (MAC) needed to block gross movement to a supra-maximal mechanical stimulus was determined for each animal. Results Between 0.9 and 1.1 MAC, halothane and isoflurane greatly reduced or abolished withdrawal force (79 and 89% reduction, respectively). Halothane (0.75-1.4 MAC) depressed heat-evoked neuronal responses in a concentration-related manner (41% reduction between 0.9 and 1.1 MAC averaged across all stimulus temperatures, P < 0.05) and decreased stimulus-response function slopes, with corresponding reductions in withdrawal force. In contrast, isoflurane did not reduce neuronal responses in the 0.75-1.4 MAC range and slightly facilitated responses (by 16%) when concentration increased from 0.9 to 1.1 MAC, despite a concurrent withdrawal force reduction. Anesthetic depression of heat-evoked withdrawal force correlated well with MAC determination using a supra-maximal mechanical stimulus. At sub-MAC anesthetic concentrations, some units exhibited firing rate changes that preceded and paralleled moment-to-moment changes in force during a given withdrawal. Conclusions Halothane reduces noxious-evoked movement at least partly via depression of dorsal horn neurons, whereas isoflurane suppresses movement by an action at more ventral sites in the spinal cord.

Depression of Collateral Blood Flow Following Arterial Thrombosis

1977 ◽  
Vol 38 (04) ◽  
pp. 0850-0862 ◽  
Author(s):  
Robert G. Schaub ◽  
Ronald Sande ◽  
Kenneth M. Meyers
Keyword(s):  
Blood Flow ◽  
Arterial Thrombosis ◽  
Hind Limb ◽  
Therapeutic Interventions ◽  
Collateral Blood Flow ◽  
Serotonin Antagonist ◽  
Limb Perfusion ◽  
Clinical Consequences ◽  
Collateral Vessels ◽  
Iliac Bifurcation

SummaryPermanent ligation of the feline aorta at the iliac bifurcation is followed by rapid opening of pre-existing collateral blood vessels. However, if ligation is combined with formation of a clot, these protective collateral vessels do not function. This study was undertaken to determine if drugs which alter serotonin function can improve collateral blood flow after arterial thrombosis. Permanent ligations were placed at the iliac bifurcation, circumflex iliac and sixth lumbar arteries in all cats. A clot was produced in the aorta of 27 cats by injection of 0.1 ml of thromboplastin. Ligated clot-occluded cats were untreated (10); had blood serotonin depleted using a single dose of reserpine (0.1 mg/kg i. m.) followed by para-chlorophenylanine (p-CPA) (100 mg/kg orally) every 3 days (9) ; or were treated prior to surgery with a serotonin antagonist cinanserin HC1 (4 mg/kg i. v.) (8). Control cats (18) were acutely ligated. 9 of these cats were untreated, 5 were cinanserin HC1-treated, and 4 were reserpine/p-CPA-treated. Extent of collateral development was assessed by aortograms 3 days after occlusion and by neurologic rating. Aortograms of acutely ligated cats indicated a significant collateral blood flow around the segment of ligated aorta, while ligated clot-occluded cats had a severely depressed hind-limb perfusion. Reserpine/p-CPA-treated ligation clot-occluded cats had aortograms similar to acutely ligated cats. The cinanserin HC1-treated ligation clot-occluded cats had aortograms which indicated hind-limb perfusion was not as adequate as the acutely ligated cats. However, the perfusion of these animals was improved over untreated ligation clot-occluded cats. Neurologic rating correlated with aortograms. These results suggest: 1) the clinical consequences of arterial thrombosis cannot be entirely attributed to mechanical occlusion of an artery, but may be due to depression of protective collateral blood flow induced by thrombosis, 2) serotonin is an important factor in this depression of collateral blood flow, and 3) isolation of the factors responsible for collateral inhibition could permit the development of therapeutic interventions.

Macroanatomical Structure of the Lumbosacral Plexus and its Branches in the Indigenous Duck

2018 ◽  
Vol 52 (1-4) ◽  
pp. 1-9 ◽  
Author(s):  
MT Hussan ◽  
MS Islam ◽  
J Alam
Keyword(s):  
Hind Limb ◽  
Femoral Nerve ◽  
Morphological Structure ◽  
Spinal Nerve ◽  
The Body ◽  
Lumbar Plexus ◽  
Lumbosacral Plexus ◽  
Sacral Plexus ◽  
Spinal Nerves ◽  
Femoral Cutaneous Nerve

The present study was carried out to determine the morphological structure and the branches of the lumbosacral plexus in the indigenous duck (Anas platyrhynchos domesticus). Six mature indigenous ducks were used in this study. After administering an anesthetic to the birds, the body cavities were opened. The nerves of the lumbosacral plexus were dissected separately and photographed. The lumbosacral plexus consisted of lumbar and sacral plexus innervated to the hind limb. The lumbar plexus was formed by the union of three roots of spinal nerves that included last two and first sacral spinal nerve. Among three roots, second (middle) root was the highest in diameter and the last root was least in diameter. We noticed five branches of the lumbar plexus which included obturator, cutaneous femoral, saphenus, cranial coxal, and the femoral nerve. The six roots of spinal nerves, which contributed to form three trunks, formed the sacral plexus of duck. The three trunks united medial to the acetabular foramen and formed a compact, cylindrical bundle, the ischiatic nerve. The principal branches of the sacral plexus were the tibial and fibular nerves that together made up the ischiatic nerve. Other branches were the caudal coxal nerve, the caudal femoral cutaneous nerve and the muscular branches. This study was the first work on the lumbosacral plexus of duck and its results may serve as a basis for further investigation on this subject.

Ameliorating effect of Cuscuta japonica chois (CJC) extract on hind-limb ischemic mice

2018 ◽  
Author(s):  
Hye Jin Kim ◽  
Dong Ho Jung ◽  
Hyun Yang ◽  
Byung Seob Ko
Keyword(s):  
Hind Limb ◽  
Cuscuta Japonica

Improved Stage Categorization of PTZ-Induced Kindling and Late Enhanced Neurogenesis in PTZ Kindled Mice

2019 ◽  
Vol 8 ◽  
pp. 1511
Author(s):  
Marzieh Shahpari ◽  
Hadi Aligholi ◽  
Mohammad Reza Namavar ◽  
Farzaneh Vafaee ◽  
Masoumeh Emamghoreishi
Keyword(s):  
Subventricular Zone ◽  
Early Phase ◽  
Hind Limb ◽  
Late Phase ◽  
The Other ◽  
Myoclonic Jerk ◽  
Ptz Kindling ◽  
First Occurrence ◽  
Tonic Extension ◽  
Behavioral Index

Background: There is no universally accepted behavioral scoring to define the early development of phenothiazine (PTZ) kindling. Therefore, studies investigating alterations of neurogenesis in the PTZ model were mainly focused on full kindled animals rather than early stages of kindling. This study aimed to determine an appropriate behavioral index for categorizing stages of PTZ kindling progress and to evaluate neurogenesis during PTZ kindling. Materials and Methods: Twenty-four mice were intraperitoneally injected with a sub convulsive dose of PTZ (40mg/kg) every other day until they became full kindled. The first occurrence of different seizure behaviors and their durations were recorded during kindling development, and the different stages of kindling were categorized. Neurogenesis was evaluated in the lateral subventricular zone (SVZ) at each stage of kindling by immunofluorescence staining. Results: First occurrence of restlessness, motionless staring, hind limb tonic extension, Straub’s tail, myoclonic jerk, and tonic-clonic were sequentially observed in more than 80% of animals with increasing PTZ injections. The duration of the myoclonic jerk was significantly longer than the other seizure behaviors. The significantly higher percentage of BrdU-positive cells was found in SVZ of mice showing tonic-clonic in comparison to other seizure behaviors. Conclusion: A hierarchy behavior was observed during the kindling process when considering the first occurrence of seizure behaviors. We defined the first occurrence of restlessness, motionless, hind limb tonic extension and Straub’s tail behaviors as an early phase, myoclonic jerk as a borderline phase and tonic-clonic as a late phase of PTZ-induced kindling. Our results indicated an enhanced SVZ neurogenesis at the late phase of kindling. [GMJ.2019;8:e1511]

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