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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of tetraethylammonium (TEA) bromide on the neurally and iontophoretically evoked endplate current (EPC) of frog sartorius muscle was investigated using voltage-clamp and noise analysis techniques, and its binding to the acetylcholine (ACh) receptor ionic channel complex was determined on the electric organ of Torpedo ocellata. TEA (250-500 microM) produced an initial enhancement followed by a slow decline in the amplitude of the endplate potential and EPC, but caused only depression in the amplitude of the miniature endplate potential and current. In normal ringer's solution, the EPC current-voltage relationship was approximately linear, and the decay phase varied exponentially with membrane potential. Upon addition of 50-100 microM TEA, the current-voltage relationship became markedly nonlinear at hyperpolarized command potentials, and with 250-2000 microM TEA, there was an initial linear segment, an intermediate nonlinear segment, and a region of negative conductance. The onset of nonlinearity was dose-dependent, undergoing a 50 mV shift for a 10-fold increase in TEA concentration. The EPC decay phase was shortened by TEA at hyperpolarized but not depolarized potentials, and remained a single expotential function of time at all concentrations and membrane potentials examined. These actions of TEA were found to be independent of the sequence of polarizations, the length of the conditioning pulse, and the level of the initial holding potential. TEA shifted the power spectrum of ACh noise to higher frequencies and produced a significant depression of single channel conductance. The shortening in the mean channel lifetime agreed closely with the decrease in the EPC decay time constant. At the concentrations tested, TEA did not alter the EPC reversal potential, nor the resting membrane potential, and had little effect on the action potential duration. TEA inhibited the binding of both [3H] ACh (Ki = 200 microM) and [3H]perhydrohistrionicotoxin (Ki = 280 microM) to receptor-rich membranes from the electric organ of Torpedo ocellata, and inhibited the carbamylcholine-activated 22Na+ efflux from these microsacs. It is suggested that TEA reacts with the nicotinic ACh-receptor as well as its ion channel; the voltage-dependent actions are associated with blockade of the ion channel. The results are compatible with a kinetic model in which TEA first binds to the closed conformation of the receptor-ionicchannel complex to produce a voltage-depdndent depression of endplate conductance and sudsequently to its open conformation, giving rise to the shortening in the EPC decay and mean channel lifetime.
J Gen Physiol 1979 Jul
PMID:Reaction of tetraethylammonium with the open and closed conformations of the acetylcholine receptor ionic channel complex. 48 41

We conducted a 30- to 40-year field follow-up of 685 patients with schizophrenia, affective disorders, and nonpsychiatric conditions. Long-term outcome was analyzed in terms of the patients' marital, residential, occupational, and psychiatric status. On the whole, psychiatric patients showed a significantly poorer outcome than the surgical controls. On the basis of long-term outcome, schizophrenia, and affective disorders, selected according to the specified research criteria, were significantly different: schizophrenia definitely showed poorer outcome than affective disorders. However, no significant differences in all four outcome variables were found between mania and depression. We hope that the present data on long-term outcome of the typical cases can be used to compare outcome of other psychiatric disorders, such as undiagnosed psychoses, having mixtures of schizophrenic and affective features. In doing this, we hope to charify our understanding of undiagnosed psychoses and their relationship to schizophrenia and affective disorders.
Arch Gen Psychiatry 1979 Nov
PMID:Long-term outcome of major psychoses. I. Schizophrenia and affective disorders compared with psychiatrically symptom-free surgical conditions. 49 48

This investigation evaluates the frequency of various subtypes of thought, language, and communication disorders in 113 patients with diagnoses of mania, depression, and schizophrenia. It indicates that some types of thought disorder considered important occur so infrequently as to be of little diagnostic value, such as neologisms or blocking. The traditional concept of thought disorder, which emphasizes associative loosening, is also of little value, since associative loosening occurs frequently in mania as well as in schizophrenia. This investigation demonstrates that associative loosening can no longer be considered pathognomonic of schizophrenia. On the other hand, an approach that defines various subtypes of thought disorder and uses a concept of negative-vs-positive thought disorder does often permit a distinction between mania and schizophrenia. It is recommended that the practice of referring globally to "thought disorder," as if it were homogeneous, be avoided in the future and instead that the specific subtypes occurring in particular patients be noted in both clinical practice and research.
Arch Gen Psychiatry 1979 Nov
PMID:Thought, language, and communication disorders. II. Diagnostic significance. 49 52

A randomized, controlled trial compared the combination of amitriptyline hydrochloride and short-term interpersonal psychotherapy, either treatment alone, and a nonscheduled treatment control group in ambulatory acute, nonbipolar, nonpsychotic depressives. Results show the efficacy of both psychotherapy and amitriptyline in overall symptom reduction. Amitriptyline and psychotherapy were about equal, and the effects of both treatments in combination were additive. The additive effect of combined treatment was largely due to the differential effects of the two treatments. Amitriptyline had its effect mainly on the vegetative symptoms of depression such as sleep and appetite disturbance, these occurred early in treatment, often within the first week. Psychotherapy had its effect mainly on mood, suicidal ideation, work, and interests; these effects occurred slightly later, at four to eight weeks.
Arch Gen Psychiatry 1979 Dec
PMID:Differential symptom reduction by drugs and psychotherapy in acute depression. 51 45

How are humans' subjective judgments of contingencies related to objective contingencies? Work in social psychology and human contingency learning predicts that the greater the frequency of desired outcomes, the greater people's judgments of contingency will be. Second, the learned helplessness theory of depression provides both a strong and a weak prediction concerning the linkage between subjective and objective contingencies. According to the strong prediction, depressed individuals should underestimate the degree of contingency between their responses and outcomes relative to the objective degree of contingency. According to the weak prediction, depressed individuals merely should judge that there is a smaller degree of contingency between their responses and outcomes than nondepressed individuals should. In addition, the present investigation deduced a new strong prediction from the helplessness theory: Nondepressed individuals should overestimate the degree of contingency between their responses and outcomes relative to the objective degree of contingency. In the experiments, depressed and nondepressed students were present with one of a series of problems varying in the actual degree of contingency. In each problem, subjects estimated the degree of contingency between their responses (pressing or not pressing a button) and an environmental outcome (onset of a green light). Performance on a behavioral task and estimates of the conditional probability of green light onset associated with the two response alternatives provided additional measures for assessing beliefs about contingencies. Depressed students' judgments of contingency were surprisingly accurate in all four experiments. Nondepressed students, on the other hand, overestimated the degree of contingency between their responses and outcomes when noncontingent outcomes were frequent and/or desired and underestimated the degree of contingency when contingent outcomes were undesired. Thus, predictions derived from social psychology concerning the linkage between subjective and objective contingencies were confirmed for nondepressed students but not for depressed students. Further, the predictions of helplessness theory received, at best, minimal support. The learned helplessness and self-serving motivational bias hypotheses are evaluated as explanations of the results. In addition, parallels are drawn between the present results and phenomena in cognitive psychology, social psychology, and animal learning. Finally, implications for cognitive illusions in normal people, appetitive helplessness, judgment of contingency between stimuli, and learning theory are discussed.
J Exp Psychol Gen 1979 Dec
PMID:Judgment of contingency in depressed and nondepressed students: sadder but wiser? 52 10

Male rats (N = 27) were given initial experience with escapable shock, equivalent amounts of inescapable shock, or no shock. Measures were then obtained in the ensuing 15 hours on food intake, water intake, number of cage crossings, and weight change for all groups. Following this, animals were tested on an escape task. Inescapably shocked animals showed significant decreases in food and water consumption in comparison to both nonshocked and escapably shocked control rats. Weight gains were significantly decreased by exposure to shock irrespective of the availability of a coping response. Consistency of these findings with proposals suggesting that exposure to inescapable shock leads to a state of animal depression (learned helplessness) is discussed and compared to alternative stress explanations.
J Gen Psychol 1977 Apr
PMID:The applicability of inescapable shock as a source of animal depression. 55 62

Leukaemia-resistant C57BL/6 mice inoculated with the Friend complex (FLC) present a transient but definite depression of the ability to develop IgM and IgG antibody-producing cells to sheep red cells (SRC). In this paper it is shown that this immunodepression cannot be attributed solely to the lymphatic leukaemia virus (LLV) component of FLC which is immunodepressive in susceptible mice. This conclusion was reached by investigating the immunological reactivity of C57BL/6 mice following inoculation with two isolates of LLV. Circumstantial evidence obtained by examining the replication of FLC and LLV, the antibody response to E. coli lipopolysaccharide (LPS) and the ability of syngeneic macrophages administered together with the antigen to restore the response to SRC points to the same conclusion. There were also indications that the low sensitivity to depression by viruses of the Friend complex exhibited by the anti-LPS antibody response is due to the mitogenic activity of this antigen.
J Gen Virol 1978 May
PMID:An analysis of the role of lymphatic leukemia virus in the immunodepression exerted by Friend complex in leukaemia-resistant C57BL/6 mice. 56 3

A study of 658 consecutive psychiatric outpatients receiving careful medical and biochemical evaluation, defined an incidence of medical disorders productive of psychiatric symptoms in 9.1% of cases. The most frequent presentations were of depression, confusion, anxiety, and speech or memory disorders. The presence of visual hallucinations was believed to indicate medical etiology until proved otherwise. Major illnesses presenting with psychiatric symptoms in order of frequency were infectious, pulmonary, thyroid, diabetic, hematopoietic, hepatic and CNS diseases. Forty-six percent of these patients suffered from medical illnesses previously unknown to either them or their physician. A plea is made for careful medical evaluation of psychiatric patients.
Arch Gen Psychiatry 1978 Nov
PMID:Physical illness presenting as psychiatric disease. 56 61

This article examines the relative merits of either partial or continuous (total) success therapy as a device for reversing learned helplessness and depression in humans. College students experienced (a) no treatment followed by either abbreviated (20 trials) or extended (40 trials) continuous success therapy, (b) soluble problems followed by either abbreviated or extended continuous success therapy, (c) insoluble problems followed by either abbreviated or extended continuous success therapy, or (d) insoluble problems followed be either abbreviated or extended partial success therapy. Subsequently, subjects in all eight groups received 40 escape-extinction trials in which aversive tones were not controllable. The results of this experiment indicated that both continuous and partial success schedules were effective in reversing depressed responding (helplessness) induced by prior exposure to insoluble problems. However, only the partial success therapy schedules produced persistent escape responding in extinction. Also, across therapy procedures, extended therapy generated more response persistence in escape extinction than did abbreviated therapy. Theoretical implications of these results are discussed, and a compatible new treatment program, labeled persistence training, is introduced.
J Exp Psychol Gen 1978 Dec
PMID:Persistence training: a partial reinforcement procedure for reversing learned helplessness and depression. 56 82

Twenty-four-hour rhythms of serum prolactin (PRL) levels were studied in seven depressive patients. Blood was collected through an indwelling catheter and the PRL level was determined by homologous double antibody radioimmunoassay. Findings showed a different pattern of secretion of prolactin among depressives as compared to the normal 24-hour rhythm of the hormone. A statistically significant elevation of PRL levels during the evening, several hours before sleep, was found. Morning PRL levels were slightly higher and the average increase of PRL level from one determination to the consecutive one was higher among the depressives. It is assumed that there may be a connection between the diurnal rhythmicity of mood, characteristic of vital depression, and the different 24-hour rhythmicity of PRL level.
Arch Gen Psychiatry 1979 Oct
PMID:Twenty-four-hour rhythm of prolactin depressive patients. 57 6


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