Orexin-A neurons, but not melanin-concentrating hormone neurons, may control short-term food intake in rats

Administration of 2-deoxy-D-glucose (400 mg/kg) and insulin (5 U/kg) stimulated food intake and induced c-Fos expression in orexin-A neurons.

• Orexin-A neurons in the hypothalamus are activated during conditions of reduced glucose availability.
• Melanin-concentrating hormone neurons did not show increased activity in response to the same conditions.
• The findings suggest distinct roles for orexin-A and melanin-concentrating hormone neurons in regulating food intake.
• Different input signals may influence the activity of these two types of neurons.

Simplified