ABSTRACT
The effects of chronic intranasal administration of 300 nmol/kg obestatin and its fragment FNAP-NH2 on behavioral activity and nociceptive threshold were examined in male Wistar rats with normal body weight or alimentary obesity. In normal rats, obestatin produced no effect on behavior and nociception, whereas FNAP-NH2 fragment enhanced risk-taking behavior. Rats with excess body weight demonstrated less pronounced risk-taking behavior and elevated nociceptive threshold in comparison with normal animals, but these differences were abolished by chronic administration of FNAP-NH2.
Subject(s)
Nociception/drug effects , Oligopeptides/pharmacology , Pain Threshold/drug effects , Peptide Hormones/pharmacology , Administration, Intranasal , Amino Acid Sequence , Animals , Anxiety/pathology , Anxiety/physiopathology , Body Weight , Eating/physiology , Male , Nociception/physiology , Obesity/pathology , Obesity/physiopathology , Pain Threshold/psychology , Rats , Rats, Wistar , Risk-TakingABSTRACT
Single administration of the obestatin fragment 1-4 (300 nmol/kg) to male Wistar rats produced a significant weight loss in male rats on observation days 5-8, while in female rats only on day 8. In addition, males demonstrated decreased risk factor in the elevated plus-maze test, but no effect of the preparation on behavior of female rats was revealed. Obestatin fragment 1-4 had no effect on corticosterone level 1 week after single administration in both females and male rats.
Subject(s)
Anti-Obesity Agents/pharmacology , Oligopeptides/pharmacology , Animals , Corticosterone/blood , Female , Male , Maze Learning , Rats, Wistar , Risk-Taking , Stress, Psychological/bloodABSTRACT
We studied the effects of anorectic peptide obestatin and its fragment (1-4) on the antioxidant defense system in animals with normal and experimentally induced increased body weight. In rats with normal body weight, no changes in activity of the antioxidant defense system 1 week after single administration of the substances. After chronic administration of obestatin and fragment (1-4) for 1 week, total antioxidant capacity of the plasma decreased; obestatin also lowered the content of TBA-reactive products. In the overweight rats, SOD-like activity in the plasma increased 1 week after chronic administration of obestatin. Hence, obestatin and its fragment (1-4) induced changes in the antioxidant defense system only after chronic administration.
