Behavior satiety

CCK is found in the digestive tract and the central and peripheral nervous systems. In the brain, CCK coexists with DA. In the peripheral nervous system, the two principal physiological actions of CCK are stimulation of gaU. bladder contraction and pancreatic enzyme secretion. CCK also stimulates glucose and amino acid transport, protein and DNA synthesis, and pancreatic hormone secretion. In the CNS, CCK induces hypothermia, analgesia, hyperglycemia, stimulation of pituitary hormone release, and a decrease in exploratory behavior. The CCK family of neuropeptides has been impHcated in anxiety and panic disorders, psychoses, satiety, and gastric acid and pancreatic enzyme secretions. 

The contribution of serotonin to specific human behaviors remains uncertain. Serotonin has been postulated to contribute to temperament or personalty traits such as harm avoidance (Cloninger, 1987) or behavioral inhibition (Soubrie, 1986), or to categorical dimensions such as OCD (Barr et ah, 1992), anxiety and fear (Charney et ah, 1990), or depression (Grahame-Smith, 1992), as well as to satiety for food consumption. It is possible that separate components of serotonin neuronal systems (i.e., different pathways or receptors) are coded for such specific behaviors. However, that may not be consistent with the neurophysiology of serotonin neuronal function. 

The neurotransmitter serotonin (5-hydroxytryptamine [5-HT]) is widely distributed in the CNS, subsuming a variety of functions including drive satiety, mood, aggression, anxiety, and compulsive and impulsive behaviors. It may be an important neurotransmitter in psychiatric symptoms commonly associated with PTSD such as aggression, obsessive/intrusive thoughts, alcohol and substance abuse, and suicidal behavior (Friedman, 1990). Suicidal behavior is known to be associated with both childhood maltreatment and low 5-HT functioning (Van der Kolk et ah, 1991 Benkelfat,... 

Antipsychotics also have been used in the treatment of anorexia nervosa. The apparent role of dopamine in feeding and satiety involves increased receptor activity, producing symptoms similar to those found in anorexia nervosa. Thus, it seems reasonable to use dopamine antagonists to alter these behaviors. It also seems appropriate to use the sedative side effects of these drugs to decrease anxiety associated with eating. 

Nishida KJ, Dougherty GG, Ellinwood EH, Rockwell WJK (1990) Effects of chronic chlorimipramine and imipramine administration on food hoarding behavior in male rats. Res Commun Psychol Psychiatry Behav 15 115-128 Rosofsky M, Geary N (1989) Phenylpropanolamine and amphetamine disrupt postprandial satiety in rats. Pharmacol Biochem Behav 34 797-803... 

CCK acts on the brain to control the appetite. Most studies involving CCK and eating behavior show that increases in the plasma levels of CCK are closely associated with satiety. CCK is concentrated in specific regions m the brain, where it acts locally. The term locally in this instance means that the hormone is produced by the brain and acts only in the brain. Further details on appetite physiology appear in the Obesity chapter. 

Presently, it is known which neuropeptides are responsible for the sensations of hunger, satiety, or thirst, drowsiness, and elicit motor activity. When this information is combined with [that about] some of the synthetic neuropeptides which, in some cases, are a million times more active than the natural ones, the potential for a very strong behavior-modifying compound. .. could exist.34... 

---