Carbonic anhydrase inhibitors are a class of pharmaceuticals that suppress the activity of carbonic anhydrase. Their clinical use has been established as anti glaucoma agents, diuretics, antiepileptics, in the management of mountain sickness, glaucoma, gastric and duodenal ulcers, neurological disorders, or osteoporosis. [1 ] [2 ] [3 ]
Acetazolamide is an inhibitor of carbonic anhydrase. It is used for glaucoma, epilepsy (rarely), idiopathic intracranial hypertension, and altitude sickness. It can act as a mild diuretic by reducing NaCl and bicarbonate reabsorption in the proximal tubule. However, the distal segment partially compensates for the sodium loss, and the bicarbonaturia will produce a metabolic acidosis, further reducing the effect.
Methazolamide is also a carbonic anhydrase inhibitor. It has a longer elimination half-life than acetazolamide and is less associated with adverse effects to the kidney. [4 ] [5 ] [6 ]
Dorzolamide is a sulfonamide and topical carbonic anhydrase II inhibitor. It is indicated for the reduction of elevated intraocular pressure in patients with open-angle glaucoma or ocular hypertension and who are insufficiently responsive to beta-blockers. Inhibition of carbonic anhydrase II in the ciliary processes of the eye decreases aqueous humor secretion, presumably by slowing the formation of bicarbonate ions with subsequent reduction in sodium and fluid transport.
Topiramate is a weak inhibitor of carbonic anhydrase, particularly subtypes II and IV. It is a sulfamate-substituted monosaccharide, related to fructose. In the US, it is approved by the U.S. Food and Drug Administration (FDA) as an anticonvulsant to treat epilepsy and Lennox-Gastaut syndrome, and also to treat migraine headaches. In rare cases, the inhibition of carbonic anhydrase may be strong enough to cause metabolic acidosis of clinical importance.
Ellagitannins extracted from the pericarps of , the pomegranate, such as Punica granatum punicalin, punicalagin, granatin B, gallagyldilactone, casuarinin, pedunculagin and tellimagrandin I, are highly active carbonic anhydrase inhibitors. [7 ]
References [ edit ]
^ Supuran CT, Scozzafava A, Conway J, ed. (2004). Carbonic anhydrase: its inhibitors and activators. Boca Raton: CRC Press. ISBN 978-0-415-30673-7.
^ Supuran CT, Scozzafava A (2000). "Carbonic anhydrase inhibitors and their therapeutic potential". Expert Opinion on Therapeutic Patents 10 (5): 575–600. doi: 10.1517/135437220.127.116.115.
^ Supuran CT, Scozzafava A, Casini A (March 2003). "Carbonic anhydrase inhibitors". Med Res Rev 23 (2): 146–89. doi: 10.1002/med.10025. PMID 12500287.
^ Bennett WM, Aronoff GR, Golper TA, et al, Drug Prescribing in Renal Failure, American College of Physicians, Philadelphia, PA, 1987
^ Product Information: Neptazane(R), methazolamide. Storz Ophthalmics Inc, Clearwater, FL, 1995a
^ Reynolds JEF (Ed): Martle: The Extra Pharmacopoeia (electronic version). Micromedex, Inc. Englewood, CO. 1995.
^ Satomi, H.; Umemura, K.; Ueno, A.; Hatano, T.; Okuda, T.; Noro, T. (1993). "Carbonic anhydrase inhibitors from the pericarps of Punica granatum L". Biological & Pharmaceutical Bulletin 16 (8): 787–790. doi: 10.1248/bpb.16.787. PMID 8220326.
External links [ edit ]