The subcellular localization of kallikrein, amylase and acetylcholine in the submaxillary gland of the guinea‐pig

Intracellular distribution of submaxillary kallikrein

“…The microsomal fraction contained regularly a small amount of kallikrein (2.6%). In experiments reported previously (Bhoola & Ogle, 1966) no kallikrein activity was detected in the microsomal fraction. However, the previous study unlike the present one was carried out on animals fasted for 12 hr before preparation of homogenates.…”

“…Nevertheless, the present evidence so far suggests an extracellular role and supports an exocrine secretion of kallikrein by the submaxillary gland (Schachter, 1960;Bhoola & Ogle, 1966 …”

“…The incubation mixture was the same as that described previously (Bhoola & Ogle, 1966). This mixture (0.1 ml.)…”

Direct evidence for the location of kallikrein in the striated ducts of the cat's submandibular gland by the use of specific antibody.

“…The experiments of Bhoola et al (Bhoola & Ogle, 1966;Bhoola, i969;Bhoola & Heap, 1970) and of Erdos et al (Chiang, Erd6s, Miwa, Tague & Coalson, 1968;Erd6s, Tague & Miwa, 1968;Geipert & Erd6s, 1971) showed that kallikrein is present in organelles resembling zymogen granules in the submandibular salivary gland of many mammals. These conclusions were arrived at by isolating populations of organelles by differential and density gradient centrifugation oftissue homogenates, measuring the kallikrein concentrations of the fractions, and then examining them under the electron Y. HOJIMA AND OTHERS microscope.…”

Communications

“…In preliminary experiments the subcellular distribution of cat pancreatic and submaxillary kallikreins (Bhoola, 1969a, b) was found to be identical with that of guinea-pig submaxillary kallikrein (Bhoola & Ogle, 1966;Bhoola, 1968) in that most of the particulate kallikrein is recovered from the zymogen or heavy mitochondrial fraction, 14-25 x 104 g min.…”