Increases in regional cerebral blood flow have been described in a variety of cerebral pathologic states, including stroke and seizure disorders. The usefulness of technetium-99m-labeled cysteinate dimer as a marker in the measurement of regional cerebral blood flow was tested in five cynomolgus monkeys. To expand the range of blood flow to beyond the normal limits, 40 mg/kg i.v. of the carboni...

This study evaluated the effect of acetazolamide on thyroid-associated ophthalmopathy (TAO). Patients with a VISA classification index equal to or more than four were enrolled in the study and were randomly assigned into two groups. In both groups, treatment was initiated using prednisolone. Patients in the case group received acetazolamide tablets 250 mg daily in addition to prednisolone. Thre...

We investigated 15 patients with one or more transient ischemic attacks (TIAs) in the internal carotid artery territory within the month following the most recent TIA. Cerebral blood flow (CBF) was measured by single-photon emission computed tomography, using intravenous xenon-133 before and after injection of 1 g acetazolamide. Six patients had severe carotid stenosis or occlusion; the other n...

Regulation of renal erythropoietin (EPO) production is based on an intrarenal oxygen sensor. Whereas the sensitivity of this oxygen sensor to variations in renal oxygen supply is well established, the influence of changes in renal oxygen consumption has not yet been elucidated. Diuretic drugs, which inhibit active sodium reabsorption, reduce tubular oxygen consumption. We therefore investigated...

Augmented breaths, or "sighs," commonly destabilize respiratory rhythm, precipitating apneas and variability in the depth and rate of breathing, which may then exacerbate sleep-disordered breathing in vulnerable individuals. We previously demonstrated that hypocapnia is a unique condition associated with a high prevalence of augmented breaths during exposure to hypoxia; the prevalence of augmen...

PURPOSE To study the effects of acetazolamide on central and peripheral visual function in patients with retinitis pigmentosa (RP) who showed no evidence of macular edema. METHODS Thirteen patients with retinitis pigmentosa participated in a preliminary study. Measures of central and peripheral visual function were obtained before and after an 8 wk period on acetazolamide. An additional 10 pa...

BACKGROUND The present study was designed to find the differences in regional cerebral blood flow and cerebrovascular acetazolamide reactivity between leuko-araiosis with and without lacunar infarction. METHODS Fifteen cases of leuko-araiosis with lacunar infarction, 15 cases of leuko-araiosis without lacunar infarction and 15 age-matched controls in which leuko-araiosis and cerebrovascular d...

Acetazolamide, a potent carbonic anhydrase (CA) inhibitor, is the most commonly used and best-studied agent for the amelioration of acute mountain sickness (AMS). The actual mechanisms by which acetazolamide reduces symptoms of AMS, however, remain unclear. Traditionally, acetazolamide's efficacy has been attributed to inhibition of CA in the kidneys, resulting in bicarbonaturia and metabolic a...

BACKGROUND AND PURPOSE The vasomotor response can be tested by means of transcranial Doppler sonography. If a constant vessel diameter is assumed, the flow velocity changes will reflect blood flow volume changes. This hypothesis is difficult to verify. Simultaneous assessment of intracranial flow velocity and extracranial flow volume changes may solve this problem. METHODS We tested vasomotor...

The effects of acetazolamide (Diamox), parathyroid hormone (PTH) and dibutyrylcyclic-adenosine 3':5'-monophosphate (db-cAMP) on fluid and 5,5-dimethyl-2,4-oxazolidinedione (DMO) absorption in the rat proximal convoluted tubule were studied by using microperfusion methods. The rate of tubular absorption of DMO was used to estimate the rate of hydrogen ion secretion. When the tubular and the peri...