kaolinite and Bacterial-Infections

This paper documents the responses of mucus-producing cells in the gills of rainbow trout (Oncorhynchus mykiss) throughout a naturally occurring outbreak of bacterial gill disease (BGD) and following exposure to experimentally induced high concentrations of ammonia and suspended solids. The responses were examined at three sites on the gill filament with three histochemical stains selected to identify the main types of mucous glycoproteins; these were periodic acid-Schiff (PAS), alcian blue pH 2.5 (AB2) and alcian blue pH 1.0 (AB1). In the BGD-infected fish, there was an increase in the numbers of PAS-positive and AB2-positive mucous cells and a corresponding decrease in AB1-positive cells. The greatest increase in mucus-producing cells occurred at the tips of the filaments, but the greatest relative change occurred at the mid-filamental (inter-lamellar) position. Fish exposed to high ammonia concentrations also had elevated numbers of mucus-producing cells, but there was no statistically significant change in fish exposed to high amounts of kaolin. The possible implications of these findings are discussed.

Topics: Ammonia; Animals; Bacterial Infections; Environmental Exposure; Fish Diseases; Gills; Kaolin; Mucus; Salmon

High molecular weight kininogen (HMWK) is a multifunctional protein that is a parent molecule for bradykinin, a cofactor for coagulation, and an inhibitor of cysteine proteases. On immunoblot, nonreduced plasma HMWK is usually two bands at 140 kd and 120 kd; reduced plasma HMWK is a single band at 120 kd. In both concentration-dependent and time-dependent experiments kaolin-activated normal plasma HMWK becomes cleaved in an ordered sequence. When nonreduced, HMWK on immunoblot in kaolin-activated plasma changes in size from a 140 kd band through a 120 kd intermediate to result in a stable 100 kd protein. When reduced, HMWK on immunoblot in kaolin-activated plasma changes from a single 120 kd band through a 56 kd intermediate to result in a stable 46 kd protein. A similar sequence of cleavage of plasma HMWK occurs when the soluble activator dextran sulfate is used to stimulate the system. Cleavage of plasma HMWK after kaolin activation occurs similarly in factor XI-deficient plasma as in normal plasma but is decreased in prekallikrein-deficient plasma. Prolonged kaolin activation of prekallikrein-deficient plasma results in HMWK cleavage to bands below 120 kd. No band of plasma HMWK below 120 kd appears in prolonged kaolin-activated factor XII-deficient plasma. In some patients with sepsis, detectable cleavage of plasma HMWK to bands below 120 kd may not be seen, even though the patient has other evidence for contact system activation. In conclusion, these studies indicate that certain cleaved patterns of plasma HMWK on immunoblot indicate prior activation of the contact system. However, the absence of these cleaved forms of plasma HMWK in a single plasma does not exclude the occurrence of contact activation.

Topics: Bacterial Infections; Blood Coagulation Factors; Dextran Sulfate; Dextrans; Humans; Immunoassay; Kaolin; Kininogens; Mitogens