Protein kinase C inhibition improves ventricular function after thermal trauma

Area of Science:

• Cardiovascular Physiology
• Biochemistry
• Trauma Research

Background:

• Trauma-induced cardiac dysfunction is linked to protein kinase C (PKC) activation and calcium (Ca2+) handling abnormalities.
• Previous research indicates that PKC activation contributes to impaired cardiac mechanical function following burns.

Purpose of the Study:

• To investigate the impact of protein kinase C (PKC) inhibition on cardiac performance and intracellular Ca2+ homeostasis in a burn injury model.
• To determine if blocking PKC can mitigate postburn cardiac dysfunction.

Main Methods:

• Anesthetized guinea pigs sustained third-degree scald burns and were resuscitated using the Parkland formula.
• Cardiac function was assessed via Langendorff preparation, and intracellular calcium concentrations ([Ca2+]i) were measured in isolated cardiac myocytes.
• Animals received either lactated Ringer's solution alone or with the PKC inhibitor calphostin C at specific time points post-burn.

Main Results:

• Burned animals exhibited significant cardiac dysfunction, characterized by reduced left ventricular pressure and impaired pressure rise/fall rates, along with elevated myocyte [Ca2+]i.
• PKC inhibition with calphostin C significantly improved all measured cardiac performance indices.
• Intracellular calcium levels in calphostin C-treated burned animals returned to levels comparable to sham-burned controls.

Conclusions:

• Protein kinase C (PKC) activation plays a critical role in mediating cardiac dysfunction following burn injury.
• PKC inhibition represents a potential therapeutic strategy to restore cardiac function and calcium homeostasis after severe burns.