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T Eccles

Publications and source records attributed to T Eccles.

4 recordsLinked to original sources

Atypical endogenous opioid systems in mice in relation to an auto-addiction opioid model of anorexia nervosa.

We have proposed that the atypical opioid system in the mouse may be representative of that in the anorexia nervosa patient and may account for a biological predisposition to the disorder. This is in the context of our auto-addiction model of anorexia nervosa in which endogenous opioids play a critical role in its etiology. Morphine activation of the endogenous opioid systems increases food intake and causes sedation in most species, including normal humans and rats. In contrast in BALB/C mice, morphine causes anorexia and hyperactivity, which we suggest may be true in the anorexia nervosa patient. A variety of atypical opioid systems have been demonstrated in different mouse strains, based on other responses. The present study examines these strains with reference to the responses relevant to our anorexia nervosa model. Three patterns are described--anorexia with hyperactivity (BALB/C and C57BL/6J mice), anorexia without hyperactivity (DBA/J mice), and a biphasic curve with hyperphagia at low doses and anorexia and hyperactivity at higher doses (CF-1 mice). Only female mice were used. These atypical opioid systems may reflect a spectrum of biological predispositions to the disorder. These strain differences may also provide useful correlations of the genetic determinants of various opiate responses and provide useful comparisons in characterizing the essential features responsible for the atypical responses.

Animals

Effects of U50,488, a selective kappa agonist, on atypical mouse opiate systems.

We have proposed that endogenous opioids play a critical role in the etiology of anorexia nervosa, mediating an auto-addiction, and that atypical opioid systems in mice may be representative of those in anorexia nervosa patients, in contrast to normal humans and rats. A biological predisposition to eating disorders may result from these atypical opioid systems. Definition of these systems as atypical is based on their responses to morphine, which are preferential for the mu receptor subtype. Three patterns have been described in four strains of mice: anorexia with hyperactivity (BALB/C and C57BL/J), anorexia without hyperactivity (DBA/J), and a biphasic curve (CF-1). The latter showed anorexia and hyperactivity at high doses but increased food intake without a change in motor activity at low doses. These patterns contrast to the increase in food intake and sedation in typical species, including rats and normal humans. In the present study, U50,488, a selective kappa agonist, increases food intake in all four mouse strains, as previously reported in rats. Thus, these two agonists have opposite effects on the atypical mouse systems, but similar effects on the typical rat system. The typical and atypical opioid systems respond oppositely to morphine but similarly to U50,488.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh

Surreptitious insulin administration in adolescents with insulin-dependent diabetes mellitus.

Six adolescents, 12 to 15 years old, with insulin-dependent diabetes mellitus were discovered to be secretively taking extra insulin, not with the intent of improving metabolic control. Large discrepancies between reported and observed insulin requirements were noted. Psychosocial problems antedated the discovery of surreptitious insulin administration in all. Psychological testing and psychiatric evaluation revealed a variety of psychiatric conditions; depression was common. In two patients surreptitious insulin administration was believed to represent suicidal behavior. In others, it appeared to represent symptom substitution when use of other health-threatening behaviors such as recurrent ketoacidosis was made increasingly difficult through appropriate intervention. Surreptitious insulin administration may be one symptom of serious underlying psychiatric dysfunction in adolescents with insulin-dependent diabetes.

Adolescent