• Lactotroph
• Left atrioventricular valve
• Lidocaine

Endocrine cell of the anterior pituitary gland responsible for synthesizing and releasing prolactin (PRL).

The one-way valve between the left atrium and left ventricle of the heart. It is also known as the bicuspid valve or mitral valve.

The direction of blood flow through the left atrioventricular valve is from the left atrium to the left ventricle.

Bicuspid valve
Mitral valve

Lidocaine is a local anesthetic and an antiarrhythmic drug. It is a commonly used local anesthetic for minor surgery and in dental procedures. Lidocaine is also used topically to relieve itching, burning, and pain from skin inflammations.

Lidocaine's mechanism of action is to block fast voltage-gated Na⁺ channels of neurons and cardiac myocytes.

Other names used for lidocaine are xylocaine and lignocaine.

Pharmacological Inhibition of Na⁺ and K⁺ Channels

Lidocaine (Wikipedia)