Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0595921 (intraocular pressure)
 11,750 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Chronic simple glaucoma, also known as open-angle glaucoma, is the cause of blindness in about 13 per cent of people on the Blind Register, and 40 per cent of these have had no treatment before registration. Patients over the age of 60 are most liable to the disease and it is rare under the age of 40; there is often a family predisposition. I carried out a routine test for the disease in 300 patients over 60 years of age in my general practice with the object of detecting chronic simple glaucoma at an early stage. Anyone with an intraocular pressure of over 23 mm of mercury in either eye was referred to a consultant ophthalmic surgeon for further investigation. Seven patients (2.3 per cent of those examined) were confirmed as suffering from chronic simple glaucoma.
J R Coll Gen Pract 1977 Oct
PMID:Early detection of chronic simple glaucoma in general practice. 61 49

Screening for glaucoma, usually by measuring intraocular pressure, has been popular, but repeated analysis indicates poor sensitivity and specificity. More extensive testing is required. Such testing should be focused on high-risk groups, including blacks and the elderly. Regular comprehensive eye examinations, on a schedule adjusted for these and other risk factors, are probably the most cost-efficient means of identifying patients with glaucoma. The primary care provider has a pivotal role: to encourage patients to undergo such examinations when warranted; and to encourage those on intraocular-pressure-lowering medications to comply with their medication use.
J Gen Intern Med
PMID:Glaucoma screening: too little, too late? 223 Oct 62

1. The time-course of the ocular effects of topical verapamil and nifedipine as well as the dose-response relationship, were studied in conscious, normotensive rabbits. 2. Both drugs caused a dose-dependent fall of intraocular pressure, which lasted 4 hr or more. 3. Log dose-response curves of both drugs show a similar peak response, but the potency of verapamil was greater that of nifedipine. 4. A fall in the intraocular pressure in the untreated eye was also observed. 5. Verapamil and nifedipine induced a reduction of the tonographic outflow facility in the treated eye.
Gen Pharmacol 1993 Sep
PMID:The topical application of verapamil and nifedipine lowers intraocular pressure in conscious rabbits. 827 Jan 76

1. Interaction between topical isoprenaline and timolol on intraocular pressure was studied in conscious rabbits through changes of the dose-response curves. 2. Both drugs caused a dose-dependent fall of intraocular pressure mainly by reducing the aqueous humour formation. 3. When combined, timolol increased the response to submaximal concentrations of isoprenaline as well as EC50 (from 2.06 x 10(-3) M to 3.63 x 10(-3) M) and slope (from 1.21 to 1.89), but peak response to isoprenaline remained unchanged. 4. Discordance between experimental and theoretical additive curves as well as an interaction index smaller than 1 show that the interaction between both drugs is synergistic.
Gen Pharmacol 1993 Mar
PMID:Evidence for a synergistic interaction between isoprenaline and timolol on intraocular pressure in conscious rabbits. 838 57

The effects of pertussis toxin on the intraocular pressure (IOP) lowering effect of clonidine and isoproterenol as well as on the inhibitory effects of clonidine and neuropeptide Y on adenylate cyclase activity of ciliary processes were studied in albino rabbits. I.v. administered pertussis toxin elicited transient changes in IOP which, however, returned to control values during 2-3 days. In the following days the IOP lowering effect of the alpha 2-adrenergic agonist clonidine was abolished and that of the nonselective beta-adrenergic agonist isoproterenol was attenuated. At the same time, the inhibitory effects of clonidine and neuropeptide Y on basal as well as stimulated adenylate cyclase activities in homogenates of ciliary processes were grossly diminished. The effects of pertussis toxin on the IOP lowering action of adrenergic agonists and on the inhibitory action of clonidine and neuropeptide Y on adenylate cyclase activity were ascribed to an impairment of the function of a G protein in ciliary processes, probably G(i) protein. It is suggested that the decrease of IOP induced by clonidine is due to inhibition of adenylate cyclase.
Gen Physiol Biophys 1993 Apr
PMID:Effects of pertussis toxin on intraocular pressure and adenylate cyclase activity of ciliary processes in rabbits. 840 17

1. Infusions of balanced salt solutions (BSS) into the eye often cause a delayed, gradual increase in intraocular pressure or outflow facility, known as the "washout" effect. The reason(s) is occult, especially at low input rates when drainage mechanisms are not overloaded by excessive volume input. However, direct, quantitative comparisons of BSSs used in ocular research have been reported infrequently. 2. We compared the effects of three BSSs on intraocular pressure and the estimated resistance to drainage after a 1-hr, low-volume infusion into the anterior chambers of the eyes of anesthetized rats. 3. The BSSs tested raised intraocular pressure (P < 0.05) after a 20-40-min delay, and the highest IOPs occurred at 1 hr. Recovery of intraocular pressure to baseline only occurred with one BSS (Dulbecco). 4. Fitting the ascending and descending portions of the mean pressure curves to an exponential revealed differences among the infusates. The Dulbecco solution resulted in minimal changes in time constant, gain, and offset during the ascending and descending periods. 5. The data obtained show that different BSSs yield pressure curves that appear grossly similar, even though there were large differences in composition and osmolality. However, the underlying changes in ocular dynamics were not identical. Thus, it may be prudent to test more than one solvent to study "washout," or to deliver drugs directly into the anterior chamber.
Gen Pharmacol 1996 Sep
PMID:Comparison of anterior chamber infusates on the intraocular pressure of intact rat eyes. 890 94

At 22-24 h after unilateral ganglionectomy (SX), intraocular pressure (IOP) was significantly (p < 0.001) reduced in SX eyes compared either with the contralateral, normally innervated eyes or with baseline measurements. SX raised prostaglandin E2 (PGE2), PGF2alpha, and neuropeptide Y (NPY) concentrations in the aqueous humor but reduced these levels in the iris-ciliary body. At 22-24 h after bilateral SX, flurbiprofen (0.03%) significantly (p < 0.001) inhibited the reduction of IOP and the elevation of PGE2 and PGF2alpha levels in the aqueous humor. We conclude that PGs mediate the reduction of IOP at 22-24 h after SX.
Gen Pharmacol 1999 Feb
PMID:Superior cervical ganglionectomy-induced lowering of intraocular pressure in rabbits: role of prostaglandins and neuropeptide Y. 1018 18

The aim of this work was to assess the effect of topical diltiazem on the ocular hypertension induced by water loading in rabbits. The effect of three different concentrations of diltiazem on the intraocular pressure rise produced by oral administration of tap water (60 ml/kg) was tested in groups of nine or ten rabbits each. When applied at the lowest concentration studied, topical diltiazem was found to enhance the intraocular pressure rise after water loading. In contrast, when applied at the highest concentration, diltiazem counteracted the ocular hypertension caused by water loading. Although diltiazem, and probably other calcium channel blockers, may be useful in the management of ocular hypertension, the data obtained suggest that these drugs may have complex actions on aqueous humor dynamics; therefore further studies in animal models for glaucoma should be carried out before their clinical evaluation in humans.
Gen Pharmacol 1999 Feb
PMID:The effect of topical diltiazem on ocular hypertension induced by water loading in rabbits. 1018 20

Aquaporin (AQP) water channels are expressed in the eye at sites of aqueous fluid production and outflow: AQP1 and AQP4 in nonpigmented ciliary epithelium, and AQP1 in trabecular meshwork endothelium. Novel methods were developed to compare aqueous fluid dynamics in wild-type mice versus mice lacking AQP1 and/or AQP4. Aqueous fluid production was measured by in vivo confocal microscopy after transcorneal iontophoretic introduction of fluorescein. Intraocular pressure (IOP), outflow, and anterior chamber compliance were determined from pressure measurements in response to fluid infusions using micropipettes. Aqueous fluid volume and [Cl(-)] were assayed in samples withdrawn by micropipettes. In wild-type mice (CD1 genetic background, age 4-6 wk), IOP was 16.0 +/- 0.4 mmHg (SE), aqueous fluid volume 7.2 +/- 0.3 microl, fluid production 3.6 +/- 0.2 microl/h, fluid outflow 0.36 +/- 0.06 microl/h/mmHg, and compliance 0.036 +/- 0.006 microl/mmHg. IOP was significantly decreased by up to 1.8 mmHg (P < 0.002) and fluid production by up to 0.9 microl/h in age/litter-matched mice lacking AQP1 and/or AQP4 (outbred CD1 and inbred C57/bl6 genetic backgrounds). However, AQP deletion did not significantly affect outflow, [Cl(-)], volume, or compliance. These results provide evidence for the involvement of AQPs in intraocular pressure regulation by facilitating aqueous fluid secretion across the ciliary epithelium. AQP inhibition may thus provide a novel approach for the treatment of elevated IOP.
J Gen Physiol 2002 Jun
PMID:Aquaporin deletion in mice reduces intraocular pressure and aqueous fluid production. 1203 63

This is a descriptive study designed to assess the predictive value of intraocular pressure (IOP) measurement in GPs' offices in an urban healthcare site using Tono-pen XL. A total of 2044 patients, aged > or =40 years, were enrolled by consecutive sampling from patients visiting the GP. Those participants who had IOP > or =21 mmHg were referred to the ophthalmologist. Of the 226 then tested, ocular hypertension was confirmed in 100 participants (4.89%, 95% CI [confidence interval] = 3.93 to 5.85%). Predictive value was 44.2%. These results suggest the validity of using Tono-pen XL in the GP's office to detect ocular hypertension.
Br J Gen Pract 2007 Aug
PMID:Predictive value of tonometry with Tono-pen XL in primary care. 1768 61


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