REPRODUCTIVE CONDITION, GLOMERULAR ADENOSINE DIPHOSPHATASE ACTIVITY, AND PLATELET-AGGREGATION IN THE RAT - EFFECT OF ENDOTOXINVISSCHER, CA., FAAS, MM., BAKKER, WW. & SCHUILING, GA., Dec-1993, In : Biology of Reproduction. 49, 6, p. 1303-1309 7 p.
Research output: Contribution to journal › Article › Academic › peer-review
In experiment A, the activity of the glomerular antithrombotic enzyme adenosine diphosphatase (ADPase) and the sensitivity of this enzyme for endotoxin (1.0 mug/kg BW) in various reproductive conditions of female rats were studied through use of enzyme histochemical methods. In experiment B, the effect of this dose of endotoxin on the thrombotic tendency of the glomeruli in pregnant (Pr) and pseudopregnant (PSP) rats was studied by means of ex vivo alternate perfusion of the kidneys with human platelets and adenosine diphosphate (ADP).
In experiment A, cyclic (C), ovariectomized (OVX), Pr, and PSP rats were infused with endotoxin or saline. Three days later (for Pr and PSP rats, Day 8), animals were killed. In intact rats (C, Pr, PSP), the activity of glomerular ADPase was the same; however, the activity decreased after OVX. Endotoxin decreased the activity of glomerular ADPase in Pr rats only. In endotoxin-treated Pr rats, spontaneously formed platelet microaggregates were present in a few glomeruli; in glomeruli of the other groups, microaggregates were not observed. Platelet microaggregates were also present in the venous microvasculature of endotoxin-treated Pr rats and, to a lesser extent, in that of other groups, while saline-treated OVX rats were negative in this respect.
In experiment B, Pr and PSP rats were treated as in experiment A; ex vivo kidney perfusion was performed on Day 8. Immediately after perfusion, rats were killed. Only Pr endotoxin-treated rats exhibited significantly increased intraglomerular platelet aggregation.
It was concluded that 1) some ovarian factor maintains the activity of glomerular ADPase at the ''intact'' (glomerular ADPase activity of cyclic rats) level; 2) at least one pregnancy-associated factor, possibly of placental origin, is responsible for the increased sensitivity of glomerular ADPase to endotoxin even early in pregnancy; and 3) exclusively in the pregnant rat, endotoxin enhances the thrombotic tendency of the glomeruli by decreasing the ADPase activity.
|Number of pages||7|
|Journal||Biology of Reproduction|
|Publication status||Published - Dec-1993|
- ANTITHROMBOTIC ACTIVITY, COAGULATION, PREGNANCY, PROLACTIN