title: Levels of pre-kallikrein in resting and stimulated human parotid and submandibular saliva.
abstract: Salivary tissue kallikrein is stored in an active form in human salivary glands. Pre-kallikrein has been demonstrated in mixed saliva, but it is not clear if the various salivary glands contribute equally. This study set out to determine if pre-kallikrein is present in human parotid and submandibular salivas at rest, whether levels change during stimulation, and to compare the pattern of pre-kallikrein and kallikrein secretion with that of total protein. Resting and citric acid-stimulated parotid and submandibular, and gum-stimulated parotid saliva samples were collected from 6 healthy subjects. Salivary flows were determined gravimetrically. Total protein concentration and kallikrein enzymic activity were assayed using standard techniques. Pre-kallikrein was assayed following trypsinisation of duplicate samples. Pre-kallikrein was present in parotid and submandibular ductal saliva. Proportions of pre-kallikrein and active kallikrein were similar in salivas secreted at rest and during stimulation, and both outputs mirrored protein output in both major glands. Gum-stimulated parotid saliva showed lower activity than resting, and no differences were seen between resting and stimulated submandibular samples.
authors.affiliation: Department of Adult Oral Health Barts & The London School of Medicine & Dentistry, Queen Mary, University of London, UK. c.a.francis@mds.qmul.ac.uk
authors.forename: C A
authors.initials: CA
authors.lastname: Francis
authors.forename: M P
authors.initials: MP
authors.lastname: Hector
authors.forename: G B
authors.initials: GB
authors.lastname: Proctor
mesh_terms: D000328:Adult; D002638:Chewing Gum; D019343:Citric Acid / Q000494:pharmacology; D005260:Female; D005470:Fluorometry; D006801:Humans; D007610:Kallikreins / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010306:Parotid Gland / Q000187:drug effects / Q000378:metabolism*; D011288:Prekallikrein / Q000032:analysis* / Q000378:metabolism; D018987:Salivary Ducts / Q000378:metabolism; D012471:Salivary Proteins and Peptides / Q000032:analysis* / Q000378:metabolism; D012636:Secretory Rate / Q000502:physiology; D013056:Spectrophotometry, Ultraviolet; D018709:Statistics, Nonparametric; D013363:Submandibular Gland / Q000187:drug effects / Q000378:metabolism*
chemical_list: D002638:Chewing Gum; D012471:Salivary Proteins and Peptides; D019343:Citric Acid; D011288:Prekallikrein; D007610:Kallikreins