Dilatantes

Dilatantes is a term used in medical and physiological contexts to refer to substances, devices, or processes that cause dilation of a hollow structure or passage in the body. This broad category covers widening of blood vessels (vasodilation), airways (bronchodilation), pupils (mydriasis), and other openings such as the cervix. In some usages, dilatantes emphasizes the action of widening an opening rather than a persistent dilated state.

Etymology and usage: the word derives from Latin dilatare, “to widen,” with dilatans or dilatantes forming the agent-noun sense in medical terminology to denote dilating factors or agents. The term appears in various languages and historic medical literature, sometimes overlapping with what clinicians would simply call vasodilators, mydriatics, or bronchodilators.

Examples and categories: vascular dilatants (vasodilators) include agents such as nitroglycerin, nitroprusside, and hydralazine that enlarge blood vessels; bronchial dilators (bronchodilators) such as beta-2 agonists like albuterol and anticholinergics; ophthalmic dilatants (mydriatics) such as phenylephrine and tropicamide; and cervical or uterine dilators (cervical ripening agents) such as prostaglandins like misoprostol or dinoprostone. Mechanical dilators and balloon dilatation devices are also used to widen strictures or passages in surgical or diagnostic procedures.

Mechanisms and contexts: dilatantes may act by relaxing smooth muscle, altering intracellular signaling (for example via cGMP or cAMP pathways), reducing intracellular calcium, or by mechanical expansion. They are employed in diverse clinical settings, including cardiovascular disease management, respiratory therapy, eye examinations, obstetrics, and endoscopic or catheter-based interventions.

See also: vasodilators; bronchodilators; mydriatics; cervical ripening agents.