Physiological Pharmaceutics

298 GlossaryTributyrase An enzyme which hydrolyses tributyrinto glycerol and butyric acid.Triceps muscle Extends forearm and arm.Tricyclic antidepressants Drugs used to treatmoderate to severe endogenous depression.Trypsin Proteolytic enzyme formed in the intestine.Trypsinogen Proenzyme of inactive form of trypsin.Tuberculin A soluble cell substance prepared fromthe tubercle bacillus used to determine thepresence of a tuberculosis infection.Tuft cells An intestinal epithelial cell of uncertainfunction.Turbinates Bones which project from the lateralnasal wall.Tween Trade name for a family of hydrophilicsurfactants produced by conjugating ethyleneoxide and fatty acids to a sorbitol nucleus.Tyrosine An amino acid.vinblastine derived from periwinkles.Antineoplastic drugs.Virus A minute organism not visible with ordinarylight microscopy. It is parasitic and reliesentirely on nutrients in host cells. They consistof a strand of DNA or RNA but not both.Viscolyzers Agents used to enhance the viscosity ofsolutions or suspensions.Viscosity modifiers See Viscolysers.Vomer The bone which forms the lower andposterior portion of the nasal septum.WWharton’s duct Duct of the submandibular salivaryglands opening into the mouth at the side ofthe frenulum linguae.Witepsol Trade name for a series of surfactants usedin some oral dose forms.UUlcer An open sore or lesion of the skin or mucousmembrane.Ulcerative colitis Inflammation and ulceration inthe colon.Urea The diamine of carbonic acid found in theblood lymph and urine. It is formed in the liverfrom ammonia derived from amino acids bydeamination. It is the main constituent in urine.Urobinin A brown pigment formed from theoxidation of urobilinogen, a decompositionproduct of bilirubin.Uveal tract The portion of the eye consisting of theiris, ciliary body, and choroid.Uvula Small soft structure hanging from the freeedge of the soft palate.VVaccines A suspension of infectious agents or partof them administered for the purpose ofestablishing resistance to an infection.Vagus The 10 th cranial nerve. It is a mixed nervewith both motor and sensory functions.Valium Trade name of diazepam.Vasoactive intestinal peptide (VIP) Peptide presentin the mucosa of the gastrointestinal tract withthe main function of inhibiting gastric functionand secretion.Vasopressin Hormone formed in the hypothalamus.It has an antidiuretic effect and pressor effectthat elevates blood pressure.Vastus One of three muscles of the thigh.Verapamil Calcium channel blocker used to treathypertension and angina.Villi Pl. of Villus. Short filamentous processes foundon certain cells, generally to increaseabsorptive area.Vinca alkaloids Drugs such as vincristine andXX-ray studies x-rays are high energy electromagneticwaves varying in length from 0.05 to 100 Å.They can penetrate solid matter to differingdegrees and act on photographic film. Hencethey are used for diagnosis and therapy. Theywere used to study the behaviour of drugformulations within the body, but theradioopaque materials adulterated theformulations nd the radiation dosimetry limitedthe number of x-rays which could be taken.Xanthines drugs such as caffeine, theophylline andtheobromine which are stimulants anddiuretics.Xerostomia Dryness of the mouth caused byreduction in the normal production of saliva.Xylan An anticoagulant poysaccharide similar toheparin.Xylometazoline A vasoconstrictor drug used to treatnasal congestion.ZZeta potential The electrical potential of a chargedparticle at its hydrodynamic plane. This issimilar to the potential at the particle surfacebut takes into account the fact that the particlenormally moves carrying a layer of adsorbedsolvent. It is the zeta potential which iscalculated from the drift velocity in anelectrophoresis experiment.Zonulae adherens See desmosomes.Zonulae occludens See tight junctions.Zymogen A substance that develops into a chemicalferment or enzymes. Zymogen granules aresecretory granules of a pre-enzyme substanceseen in cells of organs such as salivary glandsor the pancreas.