Intraglandular transport of 125I‐glandular kallikrein in the rat submandibular salivary gland
Tóm tắt
The transport of radiolabeled rat submandibular gland kallikrein was studied after local administration to the resting and activated rat submandibular gland. The iodinated kallikrein was electrophoretically, immunologically, and biologically indistinguishable from the intact enzyme. After intraductal and intraglandular application the radioactivity in venous effluent was quantitated and characterized. As judged by gel‐filtration 125I‐kallikrein in venous effluent eluted at a position similar to that seen when the iodinated enzyme was mixed with plasma, but earlier than the elution of 125I‐kallikrein in buffer. In plasma, therefore, glandular kallikrein is probably bound to macromolecules. The radioactive fractions in venous effluent did not contain free iodine. Maximum concentration of 125I‐kallikrein in venous effluent of resting glands was repeatedly reached about 20 min after intraductal administration. Moreover, the ductal epithelium represented the main permeation barrier since after intraglandular application the maximum venous 125I‐kallikrein concentration was reached almost immediately. In activated gland (parasympathetic and sympathetic nerve stimulation), the venous 125I‐kallikrein concentration was inversely related to glandular blood flow. We conclude that kallikrein present in the duct lumen or in the interstitium is able to reach the circulation, thereby making possible the local generation of plasma‐kinins.
Từ khóa
Tài liệu tham khảo
BARABASH R. D., 1976, Role of salivary kallikrein in pathogenesis of parodontosis, Vopr Med Khim, 22, 318
BEEUWEKES R., 1975, Tubular organization and vascular‐tubular relations in the dog kidney, Am J Physiol, 229, 695, 10.1152/ajplegacy.1975.229.3.695
BONO E., 1974, Simultaneous increases in kallikrein in renal lymph and urine during saline infusion, J Physiol (Lond.), 241, 127P
GARRET J. R., 1974, Secretory mechanisms of exocrine glands, 487
GAUTVIK K. M., 1976, Chemistry and biology of the kallikrein‐kinin system in health and disease. Fogarty International Center proceedings No. 27, 335
HILTON S. M., 1970, The physiological role of glandular kallikreins, Handbook of Physiol, 25, 389
MORIWAKI C., 1973, Kininogenases, kallikrein. 1st symposium on physiological properties and pharmacological rationale, 57
NUSTAD K., 1978, Radioimmunoassay of rat submandibular gland kallikrein and the detection of immunoreactive antigen in blood
ØRSTAVIK T. B., 1975, Cellular localization of kallikreins in rat submandibular and sublingual salivary glands. Immunofluorescence tracing related to histological characteristics, Acta Histochem (Jena), 54, 183
ØRSTAVIK T. B., 1978, Diffusion of 125I‐Iabelled glandular kallikrein after local administration in the rat submandibular gland (Abstract), Microvasc Res, 15, 115
PORTER K. R., 1968, Fine structure of cells and tissues, 99