Hydrostatic Pressure Measurements of Endolymph and Perilymph in a Guinea Pig Model of Endolymphatic Hydrops

1987 ◽  
Vol 96 (1) ◽  
pp. 83-95 ◽  
Author(s):  
Charles H. Long ◽  
Tetsuo Morizono
Keyword(s):  
Guinea Pigs ◽  
Endolymphatic Hydrops ◽  
Control Group ◽  
Relative Pressure ◽  
Duct Obstruction ◽  
Endolymphatic Duct ◽  
Guinea Pig Model ◽  
The Right ◽  
Electrode Technique ◽  
Made In

The primary histologic correlate of Meniere's disease is endolymphatic hydrops. From this, many investigators have postulated the existence of endolymphatic hypertension, although there have been no measurements published to substantiate this concept. Seventy guinea pigs, surgically treated with right endolymphatic duct obstruction, were later assessed by use of a micro-electrode technique that measured their en-dolabyrinthine hydrostatic pressures. For 21 of these animals, the pressures of both scala tympani (Pst) and scala media (Psm) of both ears of each animal were successfully measured. Similar measurements were made in a control group of 25 guinea pigs that had not undergone any previous surgery. For normal ears-as well as those with hy-drops-pressure differences between perilymph and endolymph (Pst - Psm) varied around 0 >2.0 mm Hg. When only the right (obstructed) ears were considered, there appeared to be a slight, relative pressure elevation (p <0.05) in scala media during the first 7 days after endolymphatic duct obstruction-and in those ears with EP, less than 70 mV. The magnitude of this pressure difference that can be attributed to the state of endolymphatic hydrops-and not to natural variability-is calculated (within 95% confidence limits) to be less than 0.5 mm Hg.

Electrocochleographic Evaluation of the Guinea Pig Model of Endolymphatic Hydrops

1997 ◽  
Vol 106 (11) ◽  
pp. 934-942
Author(s):  
Mohamed Badr-El-Dine ◽  
George M. Gerken ◽  
Karen S. Robinson ◽  
Charles G. Wright ◽  
William L. Meyerhoff
Keyword(s):  
Guinea Pig ◽  
Guinea Pigs ◽  
Endolymphatic Hydrops ◽  
Osmotic Dehydration ◽  
Pig Model ◽  
Sham Operation ◽  
Cochlear Function ◽  
Summating Potential ◽  
Guinea Pig Model ◽  
The Right

Electrocochleography (ECochG) was used to evaluate cochlear function in guinea pigs with experimentally induced endolymphatic hydrops (ELH) before and after osmotic dehydration with either glycerol or urea. We surgically induced ELH in the right ears of 9 guinea pigs, while the right ears of 6 guinea pigs received a sham operation. The left ears of the 15 animals constituted the normal group. Eight weeks after surgery, summating potential (SP) and action potential (AP) amplitudes were measured prior to and following the administration of glycerol or urea. The SPs and SP/AP ratios were reduced in all groups, with no significant differences among groups or between dehydrating agents. Some of the hydropic ears, however, did show an increased AP threshold and a recruitment effect. In measurements from 6 additional animals, serum osmolarity increased more with urea than with glycerol. The guinea pig model remains valuable for investigation of ELH, even though it differs in significant respects from ELH in humans.

The Effect of Cochleostomy on the Development of Endolymphatic Hydrops—Morphologic Changes in the Rabbit Cochlea

1988 ◽  
Vol 98 (4) ◽  
pp. 283-290 ◽  
Author(s):  
E. A. Dimitrov ◽  
L. G. Duckert ◽  
B. L. Lonsbury-Martin ◽  
G. K. Martin
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Sensory Cell ◽  
Endolymphatic Hydrops ◽  
Cell Damage ◽  
Cell Degeneration ◽  
Duct Obstruction ◽  
Endolymphatic Duct ◽  
Cochlear Partition ◽  
Scanning Electron

The present study was designed to examine the effects of cochieostomy on the development of endolymphatic hydrops in the rabbit. Fistulization of the cochlear partition and simultaneous obstruction of the endolymphatic duct was performed in one group of animals ( n = 13). Rabbits in two other groups underwent either cochleostomy (n = 6) or endolymphatic duct obstruction (n = 6) alone. Animals were terminated at 1-, 4-, and 6-week Intervals and the cochleas were examined with the light microscope to document the presence or absence of hydrops, or were evaluated with the scanning electron microscope to assess sensory-cell damage. Hydrops was observed In 67% of the animals In the combined duct-obstruction/cochleostomy group, In 100% of the duct-obstruction alone group, and In 0% of the cochleostomy alone group. Widespread sensory-cell degeneration was observed with the scanning electron microscope in the combined and the cochleostomy alone groups.

The anti-inflammatory effects of erythromycin, clarithromycin, azithromycin and roxithromycin on histamine-induced otitis media with effusion in guinea pigs

2018 ◽  
Vol 132 (7) ◽  
pp. 579-583 ◽  
Author(s):  
B Ersoy ◽  
B Aktan ◽  
K Kilic ◽  
M S Sakat ◽  
S Sipal
Keyword(s):  
Otitis Media ◽  
Middle Ear ◽  
Guinea Pigs ◽  
Otitis Media With Effusion ◽  
Study Groups ◽  
Control Group ◽  
Middle Ear Mucosa ◽  
Anti Inflammatory ◽  
The Right ◽  
Better Than

AbstractBackgroundOtitis media with effusion is a clinical manifestation characterised by inflammation of middle-ear mucosa. This study investigated the therapeutic effect of erythromycin, clarithromycin, azithromycin and roxithromycin on a histamine-induced animal model of otitis media with effusion.MethodsThe animals were divided into five groups, receiving erythromycin, clarithromycin, azithromycin, roxithromycin or saline solution. The guinea pigs in the study groups received erythromycin (40 mg/kg/day), clarithromycin (15 mg/kg/day), azithromycin (10 mg/kg/day) or roxithromycin (10 mg/kg/day) for 3 days by gastric tube. Four hours after the end of the administration, histamine solution was injected into the right middle ear.ResultsThe lowest neutrophil density value obtained using stereological techniques was in the azithromycin group (0.86 ± 0.25 × 10−5/μm3), while the highest value was observed in the control group (6.68 ± 3.12 × 10−5/μm3). The anti-inflammatory properties of clarithromycin, azithromycin and roxithromycin were similar to one another, but better than that of erythromycin.ConclusionThe use of macrolide antibiotics is recommended, as they show antibacterial and anti-inflammatory efficacy in otitis media with effusion.

Effect of Fistulae on Endolymphatic Hydrops

1975 ◽  
Vol 84 (3) ◽  
pp. 271-286 ◽  
Author(s):  
Robert S. Kimura ◽  
Harold F. Schuknecht
Keyword(s):  
Guinea Pig ◽  
Guinea Pigs ◽  
Functional Significance ◽  
Endolymphatic Hydrops ◽  
Endolymphatic Sac ◽  
Therapeutic Approaches ◽  
Membranous Labyrinth ◽  
Horizontal Canal ◽  
Endolymphatic Duct ◽  
Experimentally Induced

An experiment was performed on 31 guinea pigs to study the effect of fistulae of the horizontal canal, superior canal, common crus, and utricle on the course of experimentally induced endolymphatic hydrops. The effect of fistulae on corresponding parts of normal ears was also studied in an additional 17 animals. The results indicated a remarkable consistency in healing of the fistulae in both groups of animals. Fistulae had no significant effect on the course of endolymphatic hydrops, irrespective of whether the fistulae were made immediately before or several months after obliteration of the endolymphatic duct or whether a polyethylene strut was introduced into the membranous labyrinth. Once again, the functional significance of the endolymphatic sac was clearly apparent, for ablation of the sac consistently produced severe hydrops and atrophic changes in sensory and neural structures. Assuming that the mechanisms of labyrinth repair in the guinea pig are comparable to the higher mammalian ear, it is apparent that procedures designed to surgically fistulize the membranous labyrinth are of questionable value and are probably not rational therapeutic approaches to the management of Ménière's disease.

Effect of irradiation on guinea pig ABR thresholds

1992 ◽  
Vol 107 (6_part_1) ◽  
pp. 763-768 ◽  
Author(s):  
J. Scott Greene ◽  
Neil A. Giddings ◽  
John T. Jacobson
Keyword(s):  
Guinea Pigs ◽  
Auditory Brainstem ◽  
Control Group ◽  
Hearing Thresholds ◽  
Number Of Patients ◽  
Brainstem Response ◽  
Radiation Induced ◽  
The Difference ◽  
The Right ◽  
Temporal Bones

A significant number of patients undergo Irradiation to the temporal bone for malignancies. Conflicting reports exist regarding the effects of irradiation on hearing thresholds. Although radiation-induced otitis media and osteoradionecrosis of the ossicles with resultant conductive hearing loss are well-documented, there is disagreement regarding the effect of irradiation on sensorineural hearing. Previous animal models, relying only on behavioral tests and reflex thresholds, have failed to reveal consistent threshold shifts after irradiation. However, with the advent of auditory brainstem response (ABR) testing, a reliable objective measurement of hearing in animals is available. Hearing thresholds were determined bilaterally by ABR testing in 21 albino guinea pigs. The left temporal bones of sixteen animals were then Irradiated with a total dose ranging from 5750 to 7000 cGy over 7 weeks. The right ears of these animals, plus both ears of five nonlrradlated guinea pigs, served as controls. Follow-up threshold ABRs were obtained immediately post-irradlation (RT), and at 6 and 12 months post-RT. Average thresholds in all groups increased over time: 60 dB in the control group; 53 dB in the control ears of the Irradiated animals; and 46 dB in the Irradiated ears. There were no statistically significant increases in ABR thresholds for Irradiated ears vs. control ears. At the 6-month followup, hearing was actually better in the Irradiated ears than the control ears and this difference between ears was significantly greater than the difference at baseline ( p < 0.026). Overall, there was no evidence that irradiation produces changes in ABR thresholds.

scholarly journals Bacterial cellulose and bacterial cellulose/polycaprolactone composite as tissue substitutes in rabbits' cornea

2016 ◽  
Vol 36 (10) ◽  
pp. 986-992 ◽  
Author(s):  
Rodrigo V. Sepúlveda ◽  
◽  
Fabrício L. Valente ◽  
Emily C.C. Reis ◽  
Fabiana R. Araújo ◽  
...  
Keyword(s):  
Bacterial Cellulose ◽  
Inflammatory Process ◽  
Clinical Observation ◽  
Giant Cells ◽  
Control Group ◽  
Superficial Ulcer ◽  
The Right ◽  
Collagen Disorganization ◽  
Made In

ABSTRACT: In order to test the performance of bacterial cellulose/polycaprolactone composite (BC/PCL) and pure bacterial cellulose (BC) as tissue substitutes in rabbits' cornea, a superficial ulcer containing 5mm in diameter and 0.2mm deep was made in the right cornea of 36 rabbits, then a interlayer pocket was created from the basis of this ulcer. Twelve rabbits received BC/PCL membrane and 12 were treated with BC membranes, both membranes with 8mm in diameter. The remaining rabbits received no membrane constituting the control group. The animals were clinically followed up for 45 days. Three animals of each group were euthanized at three, seven, 21, and 45 days after implantation for histological examination of the cornea along with the implant. Clinical observation revealed signs of moderate inflammatory process, decreasing from day 20th in the implanted groups. Histology showed absence of epithelium on the membranes, fibroplasia close to the implants, lymph inflammatory infiltrate with giant cells, collagen disorganization, with a predominance of immature collagen fibers in both groups with implants. Although inflammatory response is acceptable, the membranes used does not satisfactorily played the role of tissue substitute for the cornea during the study period.

scholarly journals Effect of Endolymphatic Hydrops on Sound Transmission in Live Guinea Pigs Measured with a Laser Doppler Vibrometer

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Chen-Ru Ding ◽  
Xin-Da Xu ◽  
Xin-Wei Wang ◽  
Xian-Hao Jia ◽  
Xiang Cheng ◽  
...  
Keyword(s):  
Dynamic Behavior ◽  
Guinea Pigs ◽  
Endolymphatic Hydrops ◽  
Laser Doppler Vibrometer ◽  
Laser Doppler ◽  
Auditory Brainstem Responses ◽  
Round Window Membrane ◽  
Control Group ◽  
Strong Positive Correlation ◽  
Threshold Elevation

Objective. This study aimed at describing the mechanism of hearing loss in low frequency and the different dynamic behavior of the umbo, the stapes head, and the round window membrane (RWM) between normal guinea pigs and those with endolymphatic hydrops (EH), using a laser Doppler vibrometer (LDV).Methods. Cochlear sections were stained with hematoxylin and eosin (HE) to evaluate the hydropic ratio (HR). Auditory brainstem responses (ABR) and whole-mount immunostaining were measured. Displacement of the umbo, stapes head, and RWM in response to ear-canal sound was evaluated using a LDV.Results. Mean HR values in EH model of all the turns are larger than the control group. The ABR threshold of the EH group was significantly higher than that of the control. Strong positive correlation was found between HR at apical turn and ABR threshold elevation at 1000 Hz and at subapical turn and ABR threshold elevation at 2000 Hz. FITC-phalloidin immunostaining of the cochlear basilar membrane in the apical, subapical, and suprabasal turns showed missing and derangement stereocilia of third-row outer hair cells. The umbo, stapes head, and RWM displacement in ears with EH was generally lower than that of normal ears. The EH-induced differences in stapes head and RWM motion were significant at 0.5 kHz.Conclusion. The LDV results suggested that the higher inner ear impedance in EH affected the dynamic behavior of the two opening windows of the cochlea and then reduced the vibration of the ossicular chain by increasing the afterload, resulting in acoustic dysfunction. The vibration reduction mainly occurred at low frequencies, which has related with the morphology changes of the apical and subapical turns in EH model.

scholarly journals Effect of Arginine and Selenium with Vitamin E on WBC and the level of hormones in Iraqi ewes discharged

2019 ◽  
Vol 12 (1) ◽  
pp. 6-12
Author(s):  
I Alawiy ◽  
T Mohammed ◽  
A Majeed
Keyword(s):  
Vitamin E ◽  
Jugular Vein ◽  
Day Treatment ◽  
Control Group ◽  
Average Weight ◽  
Single Treatment ◽  
Significant Difference ◽  
The Right ◽  
Real Time Ultrasonography ◽  
Made In

This study was achieved in a special farm in Basaer village which lies on the right side of the Euphrates in Heet district l Anbar, Heet lies 70 K.M west Ramadi during the pesiod, From 17/4/2018 to 30/5/2018. 28 ewes aged 2-4 years of awassi with average weight 40-50 k.g. and a one lambing. All ewes were diagnosed by using the real-time Ultrasonography to make sure there is no pregnancy among the female before the experiment. All ewes were synchronized with intravaginal sponges impregnated with 60 mg MAP for 12 days before sponges withdrawal and eCG 500 IU (Novormon made in Argentina). The pregnant ewes were divided randomly and equally (7 each group) Into 4 groups The ewes in the first group were received an intramuscular injection of 160 Mµ of arginine 3 times daily. The second group were treated with 2ml/head a combination of selenium plus vitamin E (vitamin E 68mg/ml Selenium 1.5mg/ml). The third group was treated by injection of 160 Mµ of arginine and selenium with vitamin E 2 ml/head. The four groups were injected with normal saline which was considered as a control group. The ewes were inseminated by ram at the end of the hormonal program for five days. The samples of blood were taken from the Jugular vein at four-day treatment Also, In the 4, 10, 15, 18. The results of the experiment showed no significant deferent in WBC, Progesterone estrogen, growth hormone, prolactin, early of pregnancy in the treatment with the control group. The experiment showed a significant difference in the Progesterone concentration within a single treatment in three treatment without control. concluded from this study that use of arginine and selenium with vitamin E improves ewes health, increasing the progesterone to maintain pregnancy.

Induction of Endolymphatic Hydrops by Directly Infused Monoclonal Antibody against Type Ii Collagen CB11 Peptide

2002 ◽  
Vol 111 (7) ◽  
pp. 587-592 ◽  
Author(s):  
Hiroshi Matsuoka ◽  
Soon Seog Kwon ◽  
Marco Barbieri ◽  
Yoshiro Yazawa ◽  
T. J. Yoo
Keyword(s):  
Monoclonal Antibodies ◽  
Guinea Pigs ◽  
Auditory Evoked Potentials ◽  
Endolymphatic Hydrops ◽  
Hearing Threshold ◽  
Type Ii Collagen ◽  
Mouse Serum ◽  
Control Group ◽  
Type Ii ◽  
Scala Tympani

Autoimmune ear disease induced by type II collagen has been investigated by Yoo et al. In the present study, we investigated the effects of direct chronic infusion of type II collagen-specific monoclonal antibodies into guinea pig cochlea. Type II collagen fragment CB11 peptide-specific monoclonal antibodies (anti-CB11 Mabs) were infused directly into the scala tympani of guinea pigs with an Alzet mini-osmotic pump (anti-CB11 Mab group). As a control, normal mouse serum was infused by the same method (control group). To evaluate the auditory function, we recorded brain stem auditory-evoked potentials (BAEPs). In the anti-CB11 Mab group, 80% of the animals showed an increased hearing threshold of more than 25 dB at 7 days after infusion. The hearing threshold shift observed in the guinea pigs of the control group was minimal (15 dB or less). To detect the structural changes, we performed histopathologic studies using hematoxylin and eosin staining. Inflammatory cell migration was detected mainly in the scala tympani of the guinea pigs of both groups. In the anti-CB11 Mab group, endolymphatic hydrops was also observed. The results of this experiment suggest that type II collagen autoimmunity is responsible for the production of hearing loss and endolymphatic hydrops.

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