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

6-Hydroxydopamine treatments which preferentially depleted either norepinephrine or dopamine were used to define the importance of these transmitter systems in the behavioral alterations produced by catecholamine synthesis inhibitors and d-amphetamine on self-stimulation of the locus coeruleus and substantia nigra. After chronic reduction of brain dopamine, an acute depression of self-stimulation of both the locus coeruleus and substantia nigra occurred. Preferential depletion of norepinephrine with 6-hydroxydopamine did not result in a significant decrease in self-stimulation of locus coeruleus or substantia nigra. However, a dose of alpha-methyltyrosine wihch had no effect in control rats or in rats with brain norepinephrine depleted caused a significant reduction in responding at both electrode placements in animals depleted of brain dopamine. Administration of U-14,624 affected neither substantia nigra nor locus coeruleus self-stimulation, even though it produced an additional 70% depletion of norepinephrine. When d-amphetamine sulfate was given to 6-hydroxydopamine-treated rats, the facilitation of self-stimulation produced by this compound was significantly attenuated in rats with prior depletion of brain dopamine. Depletion of brain norepinephrine did not affect the actions of d-amphetamine on self-stimulation. In other experiments, the actions of d-amphetamine to increase self-stimulation of animals pretreated with reserpine was found to be antagonized by alpha-methyltyrosine but not by U-14,624. Results suggest that drugs can alter self-stimulation of a site in brain anatomically associated with noradrenergic neural pathways and self-stimulation of a site primarily associated with dopaminergic pathways in a similar manner. These data also provided evidence for the involvement of dopamine fibers in the pharmacological actions of d-amphetamine, reserpine and alpha-methyltyrosine.
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PMID:Effects of catecholamine depleting drugs and d-amphetamine on self-stimulation of the substantia nigra and locus coeruleus. 2 29

Suppression of growth without significant alterations in hormonal patterns has been demonstrated for the neurostimulant drug pemoline. Comparison of the in vitro effect of pemoline, methylphenidate, and methamphetamine on somatomedin-stimulated sulfate uptake by cartilage showed all three drugs to be inhibitory. Sulfate uptake by cartilage can be directly related to growth and glycosaminoglycan biosynthesis. Assay of two of the enzymes involved in the glycosaminoglycan biosynthetic pathway showed that methamphetamine and methylphenidate caused a marked depression of xylosyl- and galactosyltransferase enzyme activity. These data suggest an interference with cartilage metabolism as one possible mechanism for the growth retardation observed in children on neurostimulant drug therapy.
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PMID:Alterations in cartilage metabolism by neurostimulant drugs. 3 81

Studies on acute toxicities of pepleomycin sulfate were carried out in both sexes of mice and rats, comparing with bleomycin, and male dogs. Pepleomycin was administered subcutaneously, intravenously and intraperitoneally in both sexes of mice and rats, and intravenously in male dogs respectively. Mice and rats, and intravenously in male dogs respectively. Mice and rats were observed respectively for 10 and 14 days after the administration. LD50 values were calculated by the method of Litchifield & Wilcoxon. LD50 values of pepleomycin were 4 approximately 6 times smaller than those of bleomycin in all routes of mice, but difference between them was not significant in all routes of rats. Additionally sex-difference of LD50 values was scacely recognized in all routes of both species. Toxicological findings observed in common to all routes of both species were ataxia, depression, tremor and epiphora, and only in all routes of mice, head-twitch, running-round and rolling were especially recognized as toxic behavior, which were not observed in bleomycin. Hepatic and renal lesions were recognized in biochemically and histopathologically in the survived rats. The dogs treated with pepleomycin 50 and 30 mg/kg had the decrease in food intake and the loss of body weight. They became moribund in 9 approximately 36 days after administration. In these dogs the lesions of liver and kidney were severely recognized in biochemical and histopathological findings. One of them which received 50 mg/kg recovered biochemically and histopathologically in 209 days after administration by the supplemental nutrition in early stage.
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PMID:[Toxicological studies on pepleomycin sulfate (NK 631). I. Acute toxicity of pepleomycin in mice, rats and dogs (author's transl)]. 8 4

Hospitalized bipolar and unipolar endogenously depressed patients who showed an antidepressant response to the monoamine oxidase (MAO) inhibitor, tranylcypromine sulfate, relapsed (ie, depression returned) when relatively small doses of parachlorophenylalanine (PCPA) were added for brief periods. Considered together with our findings that PCPA similarly reversed the antidepressant effects of the tricyclic drug, imipramine hydrochloride, implications are (1) serotonergic mechanisms are likely involved in the antidepressant effects of both the tricyclic drugs and MAO inhibitors in man and (2) this indolamine may also play a role in the endogenous clinical state of depression.
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PMID:Parachlorophenylalanine reversal of tranylcypromine effects in depressed patients. 13 50

The mucosal population of small intestine of rats was exposed in vivo to various concentrations of vinblastine sulfate for 30 and 60 min and the activities of glycyl-L-valine and glycyl-L-leucine hydrolase were measured in the treated mucosa of the upper jejunal segment. A significant depression in the activity of these dipeptidases was observed which was further found to be dose dependent.
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PMID:A study of intestinal dipeptidases of rats: effect of in vivo mucosal exposure to vinblastine. 16 May 71

Cardiovascular and metabolic responses to exercise and consecutive epinephrine infusions 24 hours apart were measured in 7 normal individuals before and following a week's administration of ephedrine sulfate. There was evidence of less beta adrenergic response to the second control epinephrine infusion compared to the first control infusion, and the depression of the rise in blood lactate was significantly different. A week of ephedrine produced more profound depression of the beta adrenergic responses to epinephrine with significant differences in the rise in blood glucose and lactate, and the pulse and blood pressure responses. Furthermore, these same responses remained significantly altered when a second epinephrine infusion was performed 36 hours following the last dose of ephedrine. The alterations in the response to epinephrine induced by ephedrine are consistent with the concept of effector cell "subsensitivity," an adaptive response to prolonged excessive stimulation.
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PMID:Subsensitivity to epinephrine following the administration of epinephrine and ephedrine to normal individuals. 16 90

Trains of electrical stimuli were applied to the superior laryngeal nerve (SLN) innervating the upper respiratory tract while evoked potentials were recorded from the recurrent nerve (RN) which innervates the intrinsic laryngeal muscles. Responses of this brain stem reflex (central delay 3.5-5.0 msec) were compared to the post-tetanic potentiation (PTP) of the polysynaptic ventral root response (L6-S1) with trains of stimuli applied to the dorsal root of adult cats. Stimulation of the SLN with a train of pulses varying from 10-45/sec evokes an initial depression of the polysynaptic potential from the RN followed by a low but sustained increase in the amplitude of the integrated signal (1.2-1.6x) lasting 45-130 msec and lacking the early maximum amplitude as seen in the PTP of the polysynaptic spinal reflex. Both the early and late components of the superior laryngeal-recurrent nerve reflex (SLN-RN) demonstrate potentiation whereas the shortest latency components of the spinal reflex account for most of the PTP. Systemic administration of strychnine sulfate (dosage: 0.03-0.45 mg/kg) does not alter the normalized PTP of the SLN-RN reflex despite enhancement of both early and late components of the reflex following control stimuli at 1/sec.
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PMID:Low level potentiation of the brain stem laryngeal reflex. 18 87

Changes in spontaneous neuronal activity in the caudate-putamen, accumbens nucleus and amygdaloid complex of immunobilized, locally anesthetized rats were recorded following intraperitoneal injection of 2.5 mg/kg d-amphetamine sulfate. In each site, d-amphetamine typically produced a prolonged depression of firing rate which, in most cases, occurred after an inital, brief potentiation of activity. However, the onset of the amphetamine-induced depression occurred signficantly later in the amygdala. Subsequent IP administration of either 5.0 mg/kg chlorpromazine or 2.0 mg/kg haloperidol reversed, to varying degrees, the amphetamine-induced depression of neuronal activity in each area. These results are discussed in terms of the known biochemical effects of amphetamine on catecholaminergic transmission and the alleged role of the nigro-neostriatal mesolimbic dopamine systems in the amphetamine behavioral response.
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PMID:Alterations of spontaneous neuronal activity in the caudate-putamen, nucleus accumbens and amygdaloid complex of rats produced by D-amphetamine. 20 78

The addition of d-amphetamine to morphine has been reported to result in an increase of analgesic potency in experimental animals and man, but no data on the toxicity of such combinations are available. This study is intended to provide systematic information on the toxicity, analgesic potency and degree of physical impairment (swimming endurance) of a combination of 12 mg morphine sulfate with 10 mg d-amphetamine HCl per ml which is now under clinical investigation. Mice were used as experimental subjects. Meperidine, methadone and pentazocine were substituted for morphine using clinically equally analgesic doses and keeping the d-amphetamine amount constant. The toxicity of all analgesics especially that of morphine was enhanced in the combination, least so in the case of meperidine. The degree of increase of analgesic power by the addition of d-amphetamine was greatest with morphine and quantitatively in satisfactory agreement with present clinical experiences. However, the relationship between the increases of toxicity and of analgesia is not necessarily most favorable for this drug. For the other three analgesics increases in toxicity and analgesia were more in line, meperidine showing the best ratio. Swimming endurance was decreased with full analgesic doses of all four compounds. The presence of d-amphetamine tended to reverse this depression. The data were analyzed in relation to their possible predictive value for the use of such combinations in man for the therapeutic dose range and in the event of overdosage.
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PMID:A study of the effect of d-amphetamine on the toxicity, analgesic potency and swimming impairment caused by potent analgesics in mice. 24 3

In order to evaluate the relative sensitivity of caloric and sinusoidal angular acceleration tests, thermal and rotational stimuli were administered to cats rendered vestibulotoxic with streptomycin sulfate. Three groups of six cats each, receiving daily subcutaneous injections of saline, 100 mg/kg streptomycin or 200 mg/kg streptomycin, were administered optokinetic, caloric and sinusoidal stimuli. Vestibular responses were evaluated by changes in the total slow phase displacement of the eyes and frequency of nystagmic beats. The results demonstrated that the saline treated animals had a decrease in response consistent with habituation; whereas, experimental animals showed a marked, rapid abolition of eye movement. The decrease in response was greater for the larger dose of streptomycin. Caloric or sinusoidal acceleration tests were equally sensitive in monitoring the degree of nystagmic depression. The data suggested that sinusoidal acceleration tests could be easily applied to the clinical vestibular assessment of ototoxicity.
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PMID:Comparison of caloric and sinusoidal tests in the vestibulotoxic cat. 30 33


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