The history and rationale of using carbonic anhydrase inhibitors in the treatment of peptic ulcers. In memoriam Ioan Puscas (1932-2015).

Carbonic anhydrase (CA, EC 4.2.1.1) inhibitors (CAIs) started to be used in the treatment of peptic ulcers in the 1970s, and for more than two decades, a group led by Ioan Puscas used them for this purpose, assuming that by inhibiting the gastric mucosa CA isoforms, hydrochloric acid secretion is decreased. Although acetazolamide and other sulfonamide CAIs are indeed effective in healing ulcers, the inhibition of CA isoforms in other organs than the stomach led to a number of serious side effects which made this treatment obsolete when the histamine H2 receptor antagonists and the proton pump inhibitors became available. Decades later, in 2002, it has been discovered that Helicobacter pylori, the bacterial pathogen responsible for gastric ulcers and cancers, encodes for two CAs, one belonging to the α-class and the other one to the ß-class of these enzymes. These enzymes are crucial for the life cycle of the bacterium and its acclimation within the highly acidic environment of the stomach. Inhibition of the two bacterial CAs with sulfonamides such as acetazolamide, a low-nanomolar H. pylori CAI, is lethal for the pathogen, which explains why these compounds were clinically efficient as anti-ulcer drugs. Thus, the approach promoted by Ioan Puscas for treating this disease was a good one although the rationale behind it was wrong. In this review, we present a historical overview of the sulfonamide CAIs as anti-ulcer agents, in memoriam of the scientist who was in the first line of this research trend.

A history of glaucoma pharmacology.

The history of glaucoma pharmacology begins in 1862 with the isolation of physostigmine from the calabar bean. The discovery of epinephrine's intraocular pressure lowering capacity came along some 40 years later. During the 20th century, drug discovery and development accelerated, with the introduction of carbonic anhydrase inhibitors, beta blockers, and prostaglandin analogs. This survey of the history of glaucoma medications reviews some of the pivotal stories behind the development of the drugs that we use daily to manage our patients with glaucoma. In addition, some unmet needs that persist in glaucoma pharmacology are discussed.

[Acetazolamide--are there reasons for its revival in antiepileptic treatment?]. / Acetazolamid--verdt en renessanse i epilepsibehandlingen?

BACKGROUND: Since 1950 the carbonic anhydrase inhibitor acetazolamide has been used as an antiepileptic drug. Because of its tolerance developing properties, acetazolamide has probably been bypassed by the new antiepileptic drugs on the market. However, when taken for 14 day periods with one week's stop in between, acetazolamide is still of value in the treatment of epilepsy. MATERIAL AND METHODS: The paper discusses acetazolamide and its present use in antiepileptic treatment in the light of existing internal control and quality assurance requirements in the medical services. RESULTS: Irrespective og type of seizure, about 90% of patients have an initial reliable effect from acetazolamide, though it is uncertain how long the effect will last after repeated periods of use. As an additional drug, acetazolamide may be particularly well suited for women with menses-related seizures. INTERPRETATION: Acetazolamide may be the drug of choice when drug interaction is a problem, when rapid onset of effect is wanted, or when an additional drug is needed for a short period of time only.

Treatments of peptic ulcer.

From the late 19th century, Mount Sinai gastroenterologists declared their scepticism of the efficacy of all recommended treatments of peptic ulcer, and looked forward to trials which could distinguish between sequence and consequence, between association and causation. The rationale of all the early studies was to reduce gastric acidity, but it soon became clear that any neutralization by single doses of antacids was brief and ineffective. Winkelstein s demonstration that patients with duodenal ulcer had higher acidities not only before and after meals but also through the night hours led him to introduce a new treatment, the alkalinized intragastric milk drip together with atropine. One of the earliest controlled clinical trials at Mount Sinai compared different antacid regimes and showed that pH values above 3.5 were achieved in only about half of the patients on the various drips. When the new anticholinergic drugs were developed in the 1950s, they were found to produce sustained hypoacidity and were tried as maintenance treatment, as an alternative to acid-lowering operations. The third Mount Sinai approach was to attack the machinery of the acid-producing cell itself by an inhibitor of the enzyme producing hydrogen ions. In 1939, this enzyme had been thought to be carbonic anhydrase, but when Janowitz and Hollander tested its inhibitor, acetazolamide, and showed marked but very brief acid inhibition, they concluded that its action was too brief to be therapeutically useful. The problem was to be solved decades later by H2 receptor blockers from Britain and H+K+ATPase inhibitors from Sweden.