What does SGLT1 primarily transport across the cell membrane?

SGLT1, or Sodium-Glucose Linked Transporter 1, primarily transports glucose and sodium across the cell membrane. This transporter is a key player in the absorption of glucose in the intestines and the reabsorption of glucose in the kidneys. It utilizes the sodium gradient established by the Na+/K+ ATPase pump to move glucose into the cell against its concentration gradient. As sodium ions move down their concentration gradient into the cell, glucose is simultaneously co-transported along with sodium. This mechanism is vital for maintaining glucose homeostasis in the body, especially during digestion when glucose levels can rise significantly.

Fructose, amino acids, cholesterol, and calcium are transported by different mechanisms and transporters, which distinguishes SGLT1's specific role in glucose and sodium transport.