Inhibition of pseudocholinesterase activity in a 20-year-old gelding.

The research article sheds light on a case where a mature horse showed signs of an overly active parasympathetic nervous system due to reduced pseudocholinesterase activity, and was successfully treated with atropine and diazepam.

Introduction

• The research explores the case of a Arab crossbred gelding, a type of horse, that exhibited symptoms of an overactive parasympathetic nervous system. The parasympathetic nervous system regulates involuntary body functions like heart rate, digestion, and salivation.

Observed Symptoms

• The 20-year old gelding demonstrated signs like hypersalivation (salivating excessively), excessive sweating, maximal miosis (extreme constriction of the pupil), muscle fasciculation (spontaneous contraction of muscles), and continuous convulsions along with a tendency to lie on its side. However, it did not show any signs of diarrhea.
• These symptoms suggested the hyperactivity of the parasympathetic nervous system, which was further confirmed by the observation of low plasma pseudocholinesterase activity. Pseudocholinesterase is an enzyme that helps to break down certain drugs in the body and control nerve impulses.
• The pseudocholinesterase activity in the horse’s plasma was about 10% of the normal level, which directly contributed to these signs of overstimulation.

Treatment and Response

• The animal was administered 10 mg of atropine and 50 mg of diazepam intravenously.
• Atropine is used in horses to decrease saliva production and to help balance the function of the parasympathetic nervous system. Diazepam, on the other hand, is commonly used to control seizures and to provide sedation.
• The combined use of these two drugs showed a positive response in the gelding’s health condition, indicating successful treatment.

Conclusion

• This study thus highlights the importance of pseudocholinesterase activity in controlling parasympathetic nervous system functions and its role in overall health condition.
• Moreover, the research validates the potential use of atropine and diazepam in treating conditions resulting from the dysfunction of the parasympathetic nervous system.