Cocaine- and amphetamine-regulated transcript

Cocaine- and Amphetamine-Regulated Transcript

The Cocaine- and Amphetamine-Regulated Transcript (CART) is a neuropeptide that plays a significant role in the regulation of energy homeostasis, reward, and stress responses. It is encoded by the CARTPT gene and is widely expressed in the central nervous system, particularly in areas associated with reward and addiction.

Discovery and Structure

CART was first identified in the mid-1990s as a transcript that was upregulated in the rat striatum following administration of cocaine and amphetamine. The peptide is derived from a larger precursor protein that is cleaved to produce active fragments, which are believed to exert various physiological effects.

Function

CART peptides are involved in several physiological processes:

• Energy Homeostasis: CART is implicated in the regulation of appetite and energy expenditure. It acts as an anorexigenic factor, meaning it suppresses appetite. CART is expressed in the hypothalamus, a brain region critical for energy balance.

• Reward and Addiction: CART is expressed in brain regions associated with the reward system, such as the nucleus accumbens and the ventral tegmental area. It is thought to modulate the effects of drugs of abuse, including cocaine and amphetamines, and may play a role in addiction.

• Stress Response: CART is also involved in the body's response to stress. It is expressed in the paraventricular nucleus of the hypothalamus, which is involved in the stress response.

Clinical Significance

Research into CART has suggested potential roles in various conditions:

• Obesity: Due to its role in appetite suppression, CART is being studied as a potential target for obesity treatment.

• Addiction: Understanding CART's role in the reward system may lead to new treatments for addiction.

• Mental Health Disorders: CART may be involved in mood regulation and stress, suggesting potential implications for disorders such as depression and anxiety.

Research Directions

Ongoing research is focused on understanding the precise mechanisms by which CART influences these physiological processes and how it can be targeted for therapeutic purposes.

Also see

• Neuropeptide
• Hypothalamus
• Reward system
• Addiction
• Obesity