To see whether plasma glucose or insulin changed in anticipation of feeding, we provided seven rhesus monkeys with four-hour access to food every other day. Blood was sampled before and during a 30-minute signal which ended with food availability and before and during a 30-minute signal which was not closely and reliably linked with food availability. Plasma insulin showed no evidence of conditioning. Plasma glucose was higher during the signal than prior to the signal in both experiments. This probably reflects the arousing nature of the signal rather than appetitive-associated learning. However, the differences, while statistically significant, were probably biologically trivial because they fall within the normal fluctuations of meal-fed monkeys. Under the conditions of this experiments, it appears that conditional changes in glucose and insulin do not reliably occur in monkeys anticipating access to food.

Animals↗

PubMedDate not supplied

Adrenomedullary function in depressed patients.

In this paper from the Collaborative Depression Study (CDS)--Biological, a set of data analyses are presented which indicate that depressed states and perhaps depressed mood are associated with a greater activation of the adrenomedullary system than the sympathetic nervous system [as measured by norepinephrine (NE) and normetanephrine excretion]. For the most part this finding of predominant activation of the adrenomedullary system is seen in unipolar and not bipolar patients.

Adrenal Medulla↗

PubMedDate not supplied

The relationship of the dexamethasone suppression test to subtypes of depression and to symptomatic severity in the elderly.

Dexamethasone Suppression Tests (DSTs) were performed on 91 subjects consisting of 66 elderly outpatients diagnosed as having major depression according to RDC and 25 age- and sex-matched healthy controls. Postdexamethasone plasma cortisol levels were significantly higher in depressed patients than in normals. The depressed patients were subdivided into endogenous and nonendogenous groups by alternately, RDC and Newcastle Diagnostic Scale (NDS). A significant difference in postdexamethasone plasma cortisol levels between endogenous and nonendogenous groups was noted only when NDS was used, but this difference was found to be related to a significant difference in severity of depression.

Aged↗

PubMedDate not supplied

Lithium metabolism and intracellular electrolytes.

Lithium chloride was administered orally to swine and two different types of sheep, HK and LK. There was a pre-lithium 16-fold variation in intracellular sodium (LK greater than HK greater than swine) and a 6.5-fold variation in the intracellular potassium (swine greater than HK greater than LK). Collected plasma and erythrocytes were analyzed for lithium, sodium and potassium. The ratio of erythrocyte lithium/plasma lithium was directly related to the pre-lithium erythrocyte sodium concentration and inversely related to the pre-lithium erythrocyte potassium concentration.

Animals↗

PubMedDate not supplied

Hypercortisolemia decreases dexamethasone half-life in rabbit.

The pharmacokinetics of dexamethasone have been found to be related to endogenous hypothalamic-pituitary-adrenal (HPA) axis activity. Lower plasma dexamethasone levels in psychiatric patients (especially depressed) who are dexamethasone suppression test (DST) nonsuppressors have previously been reported. Since DST nonsuppression is one measure of HPA axis hyperactivity and is usually associated with relatively increased plasma cortisol levels and lower post dose plasma dexamethasone levels, we hypothesized that hypercortisolemia can induce a more rapid disappearance of dexamethasone from plasma. We therefore studied the kinetics of dexamethasone in rabbits before and after a period of sustained hypercortisolemia produced by administration of IM hydrocortisone acetate, a slowly absorbed salt of cortisol. Mean dexamethasone half-life decreased significantly from baseline of 1.92 h on day zero in seven rabbits to 1.17 h on experimental day 17 of induced hypercortisolemia (P < 0.001), while there was no significant change in saline treated controls (n = 3). Dexamethasone half-life had returned to the baseline levels when retested 88 days later on experimental day 105. The results indicate that pronounced hypercortisolemia decreases dexamethasone half-life in rabbits, and support the concept that increased circulating cortisol levels induce hepatic enzymes that metabolize dexamethasone. Thus, the lower postdexamethasone plasma dexamethasone levels and decreased dexamethasone half-life in DST nonsuppressors may in part reflect the effect of prior or coincident hypercortisolemia.

Animals↗

PubMedDate not supplied

Fluoxetine tenth anniversary update: the progress continues.

This tenth anniversary review/update of fluoxetine concentrates on the past 5 years of its clinical application. The mechanism of action of fluoxetine; its metabolism; its efficacy in patients with various diagnostic subgroups of depression, patients with coincident medical disease, children and adolescents with depression, patients with eating disorders, and patients with obsessive-compulsive disorder (OCD); its long-term (maintenance) efficacy; its side effects and toxicity; and pharmacoeconomic considerations are reviewed. Pharmacotherapy is currently the only proven method for treating major depressive disorder that is applicable to all levels of severity of major depressive illness. Since its introduction 10 years ago, fluoxetine has been available to psychiatrists, primary care physicians, and other nonpsychiatric physicians as full-dose effective pharmacotherapy for patients with depression. Fluoxetine has been widely prescribed by physicians knowledgeable in pharmacology and in the treatment of depression because of its proven efficacy (ie, equal to that of tricyclic antidepressants [TCAs]), its ease of administration (with full therapeutic dosing usually starting from day 1), its generally benign side-effect profile, its remarkable safety in over-dose, and its proven effectiveness in the most common depressed patient population--anxious, agitated, depressed patients--as well as in patients with various subtypes and severities of depression. In more recent years it has also proved effective in the treatment of bulimia, an entity for which only limited or inadequate treatment options had been previously available. In OCD, fluoxetine, with its more acceptable side-effect profile and greater ease of dosing, presents a favorable alternative to previous drug therapy and is useful in treating both obsessions and compulsions. Fluoxetine is currently recognized among clinicians as efficacious in treating anxiety disorders and is being used successfully in special depressed populations such as patients with medical comorbidity, elderly patients, adolescents, and children. Rapid discontinuation or missed doses of short-half-life selective serotonin reuptake inhibitors, TCAs, and heterocyclic antidepressants are associated with withdrawal symptoms of a somatic and psychological nature, which cannot only be disruptive, but can also be suggestive of relapse or recurrence of depression. In striking contrast to these short-half-life antidepressants, fluoxetine is rarely associated with such sequelae on sudden discontinuation or missed doses. This preventive effect against withdrawal symptoms on discontinuation of fluoxetine is attributed to the unique extended half-life of this antidepressant. Current studies show that the overall increased effectiveness of fluoxetine in treating depression compensates for its higher cost, compared with older drugs, by reducing the need for physician contact because of increased compliance and less need of titration, and by reducing premature patient discontinuation, thereby yielding fewer relapses, less recurrence, and less reutilization of mental health services.

Anorexia Nervosa↗

PubMedDate not supplied

[Study of 100 manic depressive patients: I. Retrospective evaluation of their treatment with lithium; various aspects of the natural history of the disease].

Explore the source record for details and available documents.

Adult↗