Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Synthetic salmon calcitonin was administered subcutaneously to 12 inpatients with several primary psychotic diagnoses. Increases in serum total calcium and inorganic phosphorus levels and decreases in CSF calcium level had earlier been observed during periodic psychotic agitation or mania. By contrast, calcitonin, which decreased serum calcium and phosphorus levels and increased CSF calcium level, appeared to produce transient (24-hour) increases in depression and decreases in arousal in this double-blind placebo-controlled trial. Quantitative activity monitoring confirmed the rater's impression that this agent had tranquilizing or depressant effects in such patients. When given in the evening, this polypeptide also appeared to delay sleep onset, as demonstrated both by nurses' 30-minute sleep checks and by the same longitudinal activity record. A decreased hypocalcemic response to calcitonin was noted in the agitated patients, which might explain the increases in serum calcium level described at the "switch".
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PMID:Use of calcitonin in psychotic agitation or mania. 76 Jun 98

Studies of regional cerebral blood flow in migraine with aura have shown that the aura phase is associated with hypoperfusion in the cortical area which relates topographically to the clinical symptoms. Thus, the previously hypoperfused area becomes hyperperfused. However, there is no strict association between hyperperfusion and headache. The mode of hypoperfusion propagation recalls the circulatory manifestations of experimental cortical spreading depression. In addition, there are no focal cerebral blood flow abnormalities in migraine without aura. During the headache phase of migraine, dilation of both the large extra- and intracranial arteries takes place. A bulk of biochemical evidence has suggested that the pain in migraine is caused by blood vessels which are dilated and sensitized by circulating pain-producing substances e.g. bradykinin, serotonin and histamine (sterile inflammation). Recently, perivascular trigeminal fibres (trigeminovascular system) which, when stimulated, release sensory peptides (substance P and the calcitonin gene-related peptide) capable of provoking marked vasodilation and plasma extravasation (neurogenic inflammation) have been identified. Thus, the activation of the trigeminovascular system is probably involved in the vasodilatative and nociceptive phenomena of the migraine attack. The finding of a reduced endorphinergic brain tonus in migraine patients supports the hypothesis of a central nociceptive derangement in migraine. Nonetheless, the exact relationship between vasodilation and headache remains to be defined. However, the potent antimigraine effectiveness of sumatriptan--an agonist of the serotonin receptors which selectively constricts dilated arteries during the migraine attack--once again stresses the fact that serotonin is probably the crucial factor in the link between vasodilation and headache.
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PMID:[The pathogenetic bases of hemicrania]. 129 98

1. The activity of rat alpha and beta calcitonin gene-related peptide (CGRP) as compared to the structurally related peptide, rat amylin, has been investigated in the guinea-pig isolated left atrium (electrically driven), in mucosa-free strips from the base of the guinea-pig urinary bladder and in the rat isolated vas deferens (pars prostatica). The antagonist activity of the C-terminal fragment of human alpha CGRP, alpha CGRP(8-37), was also investigated. 2. In the guinea-pig isolated left atrium the three peptides produced a concentration-related positive inotropic effect, amylin being about 16 and 31 times less potent than alpha or beta CGRP, respectively. Human alpha CGRP(8-37) produced a rightward displacement of the log concentration-response curve to the three agonists tested, without depression of maximal response attainable. Apparent pKB values calculated on the basis of the displacement produced by 1 microM human alpha CGRP(8-37) indicated an agonist-independent affinity of the antagonist (6.66 +/- 0.11 for alpha CGRP, 6.42 +/- 0.17 for beta CGRP and 6.95 +/- 0.11 for amylin). 3. In the guinea-pig isolated urinary bladder, alpha or beta CGRP or amylin produce a concentration-related inhibition of twitch contractions evoked by train electrical field stimulation (10 Hz frequency, 0.25 ms duration at 100 V for 0.5 s every 60 s). Amylin was about 100 times less potent than alpha or beta CGRP. Human alpha CGRP(8-37) (3 microM) did not significantly affect the inhibitory action of the three agonists tested.4. In the rat isolated vas deferens, a or PCGRP or amylin produced a concentration-related inhibition of twitch contractions evoked by electrical field stimulation (0.2 Hz frequency, 0.5 ms duration at 60 volts). Amylin was about 100 times less potent than a or PCGRP. Human aCGRP(8-37) at 3 microM did not significantly affect the inhibitory action of amylin and at 3 microM antagonized the responses to rat a and PCGRP with apparent pKB values of 5.86 +/- 0.15 and 6.11 +/- 0.13, respectively.5. These findings indicate that multiple receptors mediate the actions of peptides of the CGRP/amylin family in the preparations investigated. In the guinea-pig atrium both a and P forms of rat CGRP as well as amylin act by stimulating a single class of receptors which are sensitive to the inhibitory action of human aCGRP(8-37). In rat isolated vas deferens, at least two receptors could be present, one activated by a and PCGRP and partially sensitive to human aCGRP(8-37) and another which is sensitive to amylin but not recognised by human aCGRP(8-37). This latter type of receptor could be entirely responsible for the action of the agonists in the guinea-pig urinary bladder.
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PMID:Involvement of multiple receptors in the biological effects of calcitonin gene-related peptide and amylin in rat and guinea-pig preparations. 133 Jan 81

Intraperitoneal or intracerebral injections of calcitonin in the rat produce several behavioral and hormonal effects which have some analogies with the human depressive syndrome. To determine if calcitonin effects are sensitive to antidepressant drugs, the ability of antidepressants and other psychotropic drugs to interact with calcitonin-induced anorexia was tested. The results show that chronic treatments (21 days) with tricyclic, or with tetracyclic, antidepressants significantly tend to neutralize the anorectic effect of calcitonin. Other antidepressants and other psychotropic drugs had no significant effect. The acute administration (24 h) of clomipramine did not antagonize the effect of calcitonin, and even significantly enhanced it. These results allow the author to propose the effects of calcitonin in the rat as a new animal model of depression, and to raise the hypothesis that a possible mechanism of action of tricyclic antidepressant treatments is to counteract the effects of certain brain peptides.
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PMID:Antagonism of calcitonin-induced anorexia by chronic, but not acute, tricyclic antidepressants in the rat. 149 68

Parathyroid hormone and calcitonin, two major calcium-regulating hormones, were measured in the plasma of five experimental groups of rats to evaluate postflight calcium homeostasis after the 14-day COSMOS 2044 flight. Parathyroid hormone values were slightly higher in the flight animals (F) than in the appropriate cage and diet controls (S) (44 +/- 21 vs. 21 +/- 4 pg/ml, P less than 0.05), but they were the same as in the vivarium controls (V), which had different housing and feeding schedules. Neither V nor S showed the increase in plasma creatinine phosphorus and magnesium found in F, features of early renal insufficiency. F showed the lowest mean plasma calcitonin that was statistically different from V only. This difference in F and V (22 +/- 11 vs. 49 +/- 16 pg/ml, P less than 0.05) was most likely due to failure of circulating calcitonin in F to show the normal age-dependent increase we demonstrated in age-matched controls in a separate experiment. Basal values for parathyroid hormone and calcitonin were unchanged after 2 wk of hindlimb suspension, a flight simulation model, in age-matched and younger rats. From a time course experiment serum calcium was higher and parathyroid hormone lower after 4 wk than in ambulatory controls. Postflight circulating levels of parathyroid hormone appear to reflect disturbances in calcium homeostasis from impaired renal function of undetermined cause, whereas levels of calcitonin reflect depression of a normal growth process.
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PMID:Circulating parathyroid hormone and calcitonin in rats after spaceflight. 152 47

Seasonal affective disorder is a form of depression which recurs at the same time of the year. Exposure to bright artificial light at a dose of 2,500 lux is used to treat seasonal affective disorders. We exposed a pigmented (Brown Norway) and a nonpigmented (Sprague-Dawley) rat strain with bright artificial light for 21 days at two doses (2,500 and 6,100 lux) and analyzed dopamine, dihydroxyphenyl-acetic acid, 5-hydroxytryptamine (5-HT), and 5-hydroxyindole-acetic acid (5-HIAA) by high performance liquid chromatography (HPLC) and electrochemical detection in eight different brain regions. Furthermore, we measured tissue levels of substance P (SP), neurokinins (NK), vasoactive intestinal polypeptide (VIP), calcitonin gene-related peptide (CGRP), and neuropeptide Y (NPY) with radioimmunoassay. Our data obtained with light microscopy show that bright artificial light at both doses induced a massive destruction of photoreceptors in the retina of albino rats but not of the pigmented rat strain. Retinal lesion of photoreceptors resulted in increased tissue levels of all measured neuropeptides except SP in the hypothalamus and increased VIP in the ventral tegmental area/substantia nigra. Furthermore, increased 5-HT and 5-HIAA tissue levels were found in the ventral tegmental area/substantia nigra. In contrast, in the frontal cortex there was a significant reduction in 5-HIAA tissue levels and a decreased 5-HIAA/5-HT ratio, indicating decreased 5-HT metabolism. Light exposure of the pigmented rat strain revealed no changes in the measured biogenic amines and neuropeptides in any investigated brain region. Our data suggest that retinal lesion but not direct visual neurotransmission induced changes in neurotransmitters in some brain regions. We conclude that Brown Norway rats but not Sprague-Dawley rats are useful to study neurochemical effects of bright artificial light. However, Sprague-Dawley rats may be a useful tool to study biochemical mechanisms of photoreceptor damage by bright light.
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PMID:Effects of bright artificial light on monoamines and neuropeptides in eight different brain regions compared in a pigmented and nonpigmented rat strain. 152 5

Progress in migraine research has been rapid in recent years, from both the basic science and the clinical perspectives. A new internationally accepted headache classification with operational diagnostic criteria was published in 1988, eliminating much diagnostic uncertainty. More than a decade of study of regional cerebral blood flow (rCBF) has gradually shown a pathognomonic pattern of abnormalities, probably reflecting spreading cortical depression. Recently it has been shown that pain probably arises from excitation of perivascular pial arterial nociceptors. The innervation and receptor mechanisms of pial and extracranial arteries have been worked out in detail both in animal and humans. Involvement of calcitonin gene-related peptide (CGRP) and 5-hydroxytryptamine (5-HT) during migraine attacks has been demonstrated. A new and specific 5-HT1D receptor agonist has proved to be highly effective in treating migraine. Therefore, major research efforts recently have been concentrated on discovering the location and function of 5-HT1D receptors, extra- and intracranially. Thus, it is now possible to formulate useful neuroscientific research strategies aimed at clarifying migraine mechanisms.
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PMID:Migraine: a research field matured for the basic neurosciences. 170 30

We report a case of severe hypercalcaemia in a 16-year-old patient, 24 weeks after immobilization for quadriplegia. The biochemical and histomorphometric parameters showed increased osteoclastic resorption and decreased osteoblastic formation. Hydration, chair sitting, salmon and porcine calcitonin, sodium etidronate were unable to normalize the hypercalcaemia. The new antiosteoclastic agent, 3-amino-1 hydroxypropylidene-1, 1-bisphosphonate (AHPrBP), was effective in normalizing serum calcium and biochemical parameters of osteoclastic activity within five days. Bone histomorphometry showed a marked reduction in osteoclastic activity after AHPrBP treatment, as well as a drastic depression of osteoblastic activity, presumably due to the reduction of bone turnover. This case represents to our knowledge, the first successful use of AHPrBP in the treatment of immobilization hypercalcaemia.
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PMID:Aminohydroxypropylidene bisphosphonate (AHPrBP) treatment of severe immobilization hypercalcaemia in a young patient. 179 Jun 47

Severe hypercalcemia is a medical emergency requiring urgent treatment. It most commonly is caused by malignant tumors, as in the case study, but can also be caused by advanced hyperparathyroidism or high serum levels of vitamin D. The patient described in the case study shows clinical evidence of volume contraction due to hypercalcemia-related anorexia and vomiting. His elevated serum concentrations of urea nitrogen and creatinine reflect intravascular volume depletion and hypercalcemia-induced reduction of renal perfusion. He is also likely to have irreversible renal damage as a result of nephrocalcinosis. His central nervous system depression is most likely a result of hypercalcemia, but other central nervous system disorders such as cerebral metastases should be considered. Appropriate treatment would include intravenous fluids to correct volume depletion, dilute extracellular fluid calcium, and promote renal calcium excretion. Before waiting for the effects of volume expansion, the first dose of an inhibitor of bone resorption should be given. The agent of choice now (this may change when second-generation bisphosphonates become available) is plicamycin. Etidronate is a reasonable second choice. Because both drugs require at least 48 hours before their hypocalcemic action is manifest, calcitonin could be used to accelerate the rate of decline of the serum calcium. As the patient becomes more alert, weight-bearing and ambulation should be encouraged. With this combination of therapeutic modalities, this patient's serum calcium level should be corrected within 3 to 5 days. Intermittent injections of mithramycin or etidronate could be given on an outpatient basis approximately once a week in order to maintain the serum calcium within the normal range. One of the most important aspects of treatment in hypercalcemic patients is eradication of the underlying disease, which usually calls for specific antitumor therapy, including chemotherapy, radiation therapy, or surgery. Most of the agents currently available for the correction of hypercalcemia have cumulative toxicities or are only transiently effective and, therefore, their use should be considered a temporizing measure until specific treatment directed at the primary disease takes effect.
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PMID:Management of severe hypercalcemia. 200 13

We have examined the effect of perivascular denervation on the ability of acetylcholine to produce endothelium-dependent relaxation in the isolated perfused mesenteric arterial bed. Treatment with capsaicin prevented the development of substance P and calcitonin gene-related peptide containing perivascular nerve fibres. Treatment with 6-hydroxydopamine prevented the development of catecholaminergic perivascular nerve fibres. In the arterial beds from capsaicin treated rats there was a depression of the ability of Acetylcholine to produce endothelium dependent relaxation. No change in endothelium-dependent relaxation to ACh was found in 6-hydroxydopamine treated rats.
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PMID:The effect of perivascular denervation on endothelium-dependent relaxation to acetylcholine. 211 55


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