Experimental hypercalcaemia and whole blood clotting

Area of Science:

• Biochemistry
• Physiology
• Hematology

Background:

• Hypercalcaemia, elevated serum calcium levels, can arise from various conditions, including malignancy and exogenous administration.
• The relationship between hypercalcaemia and blood coagulation is not fully understood.
• Understanding this interaction is crucial for managing potential thrombotic complications in hypercalcaemic patients.

Purpose of the Study:

• To investigate the effect of experimentally induced hypercalcaemia on blood clotting parameters in rats.
• To determine if acute hypercalcaemia influences the coagulation cascade and promotes a hypercoagulable state.

Main Methods:

• Hypercalcaemia was induced in rats via Walker 256 tumor transplantation or calcium gluconate injections.
• Whole blood clotting was assessed using thromboelastography and whole blood clotting times in polystyrene and glass tubes.
• Factor XII activation was utilized to normalize clotting times for comparison.

Main Results:

• Mild hypercalcaemia (10.3-11.5 m-equiv/l) showed a slight, reversible delay in clot formation.
• Acute hypercalcaemia significantly shortened clotting times, particularly in polystyrene tubes.
• Maximal Factor XII activation abolished the observed differences in clotting times.

Conclusions:

• Acute hypercalcaemia induces a hypercoagulable state in rats.
• This hypercoagulability may be mediated by partial contact activation pathways.
• The findings suggest that acute hypercalcaemia could promote in vivo thrombus formation.