Creatine kinase in the dog: a review

Area of Science:

• Veterinary Medicine
• Biochemistry
• Canine Health

Background:

• Creatine kinase (CK) is a key enzyme found predominantly in canine skeletal muscle, myocardium, brain, and intestine.
• The MM isoenzyme is the primary form in muscles and myocardium, while CK-MB constitutes 30-45% of total plasma CK activity.
• Plasma CK levels are influenced by age and physical activity, with higher levels in younger dogs and post-exercise.

Purpose of the Study:

• To summarize the physiological distribution and behavior of creatine kinase (CK) in dogs.
• To outline the primary causes of elevated plasma CK in canine conditions.
• To highlight the utility of plasma CK measurement in diagnosing muscle diseases and myocardial infarction in dogs.

Main Methods:

• Review of existing literature on canine creatine kinase.
• Analysis of factors influencing plasma CK levels (age, exercise, sex).
• Identification of pathological conditions associated with elevated plasma CK.

Main Results:

• CK is primarily located in muscle tissues, with MM isoenzyme predominance.
• Plasma CK levels increase after exercise and are higher in young dogs.
• Various muscle diseases (myopathies, malignant hyperthermia, hypothyroidism) and myocardial infarction lead to elevated plasma CK.
• CK is cleared rapidly from plasma with a half-life of approximately 2 hours, mainly via the lymphatic system.

Conclusions:

• Plasma creatine kinase is a sensitive indicator of muscle damage and myocardial events in dogs.
• Measurement of total CK activity aids in quantifying damage in conditions like experimental myocardial infarction.
• Understanding CK levels and their causes is crucial for canine diagnostics and research, particularly using dogs as a model for cardiac studies.