Disease relevance of Perilymph

• At 15 min after ischemia, most of the nerve endings at the base of the inner hair cells were protected from damage when 1 mM S-NC or NTG was infused into the perilymph [1].
• The effect of hypothermia on ischemic injury of the cochlea in gerbils was studied with particular regard to glutamate efflux in the perilymph [2].
• Since cochlear perilymph is thought to be an ultrafiltrate of cerebral spinal fluid, gadodiamide (gadolinium-diethylenetriamine penta-acetic acid [DTPA] bismethylamide), a nonionic paramagnetic contrast agent, was injected intrathecally in an attempt to enhance imaging of the created fistula [3].
• Perfusion of the perilymph with streptomycin through an opening in the bony lateral semicircular canal is the operation of choice for Meniere's disease, benign paroxysmal postural vertigo and other forms of vertigo [4].
• In decreasing order of occurrence findings were sequelae of otitis media, otosclerosis, oval and round window changes including perilymph leakage, congenital and traumatic fixation and disarticulation of ossicles [5].

High impact information on Perilymph

• Evidence that amikacin ototoxicity is related to total perilymph area under the concentration-time curve regardless of concentration [6].
• Netilmicin concentrations again were somewhat lower in the tissues, but identical to those of the other drugs in the perilymph [7].
• These results indicate that the amikacin concentration in perilymph is not solely dependent upon its concentration in plasma and that other factor(s) can affect the entry of amikacin into the inner ear [8].
• Perfusion with perilymphs containing 0.5-15 mM of the potassium channel blocker, tetraethylammonium bromide (TEA) reduced the hair cell's frequency selectivity, whether assayed acoustically or with extrinsic currents [9].
• Effect of pentobarbital anesthesia on amikacin concentrations in plasma and perilymph and evaluation of multiple sampling in perilymph of guinea pigs [8].

Chemical compound and disease context of Perilymph

• Hearing loss and glutamate efflux in the perilymph following transient hindbrain ischemia in gerbils [10].
• The apical, middle and basal parts of the organs of Corti (newborn rat, postnatal days 3-5) were exposed to ischemia (3.5 h) in glucose-free artificial perilymph (pO2 10-20 mmHg) with or without growth factors [11].
• The level of NO in the cochlea after 20 to 120 minutes of ischemia was indicated by measurement of nitrites/nitrates in the perilymph [12].
• The results of studies on the pharmacokinetics of azlocillin in the perilymph of the guinea pig following the intramuscular administration of 200 mg per kg body weight are shown graphically [13].
• In magnesium (Mg)-deficient rats and guinea pigs, noise-induced hearing loss (NIHL) was found to be correlated to the decrease of Mg in serum and perilymph [14].

Biological context of Perilymph

• The purpose of this study was to determine whether a multiple-sampling procedure could be used in guinea pigs to study the kinetics of amikacin in perilymph [8].
• Pharmacokinetics of gentamicin in perilymph and endolymph of the rat as determined by radioimmunoassay [15].
• In the absence of chronic stimulation, spiral ganglion cell survival was relatively symmetric in animals treated unilaterally with either artificial perilymph or verapamil (50 microg/ml) [16].
• A further slight N-methyl-D-aspartate-induced decrease of the amplitude of the compound action potential, although non significant, was observed when the Mg2(+)-free perilymph contained 100 or 1000 microM glycine [17].
• CONCLUSION: OPG, a potent inhibitor of osteoclast formation and function, is expressed at high levels within the inner ear and is secreted into the perilymph and the surrounding bone and may serve to inhibit active bone remodeling within the otic capsule, especially immediately adjacent to the cochlea [18].

Anatomical context of Perilymph

• Effect of sound stimulation at several levels on concentrations of primary amines, including neurotransmitter candidates, in perilymph of the guinea pig inner ear [19].
• The present study investigates the pharmacokinetics of caroverine in the perilymph, cerebrospinal fluid (CSF) and plasma following intravenous and local applications at different dosages [20].
• Two weeks of treatment with BDNF (brain derived neurotrophic factor) administered chronically via a mini-osmotic pump into scala tympani at 50 ng/ml, provided a statistically significant enhanced SGC survival over untreated deafened ears or deafened ears treated with artificial perilymph [21].
• Cells cultured in artificial perilymph nominally containing no calcium and those to which EGTA was added still showed a maximal increase in intracellular calcium level when treated with toluene [22].
• Cochleas of adult guinea pigs and rats, and 6-day-old rat pups, were injected, through the round window, with 2 microliters of artificial classical Konishi perilymph containing 1 nmol kainic acid (KA) [23].

Associations of Perilymph with chemical compounds

• The concentration of gentamicin in perilymph was linearly related to its concentration in plasma, which depended on the rate of infusion [15].
• The concentrations of amikacin in perilymph were dose proportional and increased slowly during the 6-h infusion [8].
• Retention was clearly demonstrated in perilymph, in which the half-lives of gentamicin, tobramycin, and amikacin were 12, 11, and 10 hr, respectively [24].
• It was decreased when the perilymph chloride was reduced to 50-70 mM and could be abolished when the perilymph chloride dropped to about 5 mM [25].
• In addition, a methionine-enkephalin-like component, distinct from leucine-enkephalin, was detected in perilymph from control animals and was elevated in response to noise at 115 decibels [19].

Gene context of Perilymph

• Taken together, the data suggest that the Ad.IL-1ra-infected cochlear cells synthesized the transgenic human IL-1ra protein, which was then secreted by the cells into the perilymph, resulting in an accelerated neuronal degeneration in hair cell-depleted ears [26].
• These results suggest that GLAST plays an important role in keeping the concentration of glutamate in the perilymph at a nontoxic level during acoustic overstimulation [27].
• BDNF or artificial perilymph (AP) was delivered continuously for 28 days [28].
• The perilymph contains antibody, presumably derived from the systemic circulation and CSF, which would allow for neutralization and help with opsonization and complement fixation [29].
• An attempt was made to use beta 2-transferrin, as well as apo D and apo J (NA1/NA2), as markers for the diagnosis of perilymph fistula, one of the most controversial and challenging problems for the otologist today [30].

Analytical, diagnostic and therapeutic context of Perilymph

• A commercially available radioimmunoassay kit was modified to enable us to measure, in triplicate, the amikacin concentration in 1 microliter of perilymph fluid [31].
• Amikacin levels in plasma and perilymph were measured in guinea pigs after continuous intravenous infusion at four different dosing rates [31].
• Analysis of aminoglycoside antibiotics as benzoyl derivatives by high-performance liquid chromatography and its application to the quantitation of neomycin in the perilymph [32].
• To evaluate the level of cortisol within the perilymph after intravenous administration of 125 and 250 mg of prednisolone, serum and perilymph samples of 29 consecutive patients with clinical otosclerosis subjected to stapedectomy were collected [33].
• Acoustic stimulation increased ex vivo PGI2 and PGE2 synthesis without modifying PG levels in perilymph [34].

References