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Rothe N, Steffen J, Penz M, Kirschbaum C, Walther A. Examination of peripheral basal and reactive cortisol levels in major depressive disorder and the burnout syndrome: A systematic review. Neurosci Biobehav Rev 2020; 114:232-270. [DOI: 10.1016/j.neubiorev.2020.02.024] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 01/27/2020] [Accepted: 02/19/2020] [Indexed: 12/15/2022]
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α2 Adrenergic Receptor Trafficking as a Therapeutic Target in Antidepressant Drug Action. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 132:207-25. [DOI: 10.1016/bs.pmbts.2015.03.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Cottingham C, Wang Q. α2 adrenergic receptor dysregulation in depressive disorders: implications for the neurobiology of depression and antidepressant therapy. Neurosci Biobehav Rev 2012; 36:2214-25. [PMID: 22910678 DOI: 10.1016/j.neubiorev.2012.07.011] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 06/27/2012] [Accepted: 07/25/2012] [Indexed: 12/25/2022]
Abstract
Dysfunction in noradrenergic neurotransmission has long been theorized to occur in depressive disorders. The α2 adrenergic receptor (AR) family, as a group of key players in regulating the noradrenergic system, has been investigated for involvement in the neurobiology of depression and mechanisms of antidepressant therapies. However, a clear picture of the α2ARs in depressive disorders has not been established due to the existence of apparently conflicting findings in the literature. In this article, we report that a careful accounting of methodological differences within the literature can resolve the present lack of consensus on involvement of α2ARs in depression. In particular, the pharmacological properties of the radioligand (e.g. agonist versus antagonist) utilized for determining receptor density are crucial in determining study outcome. Upregulation of α2AR density detected by radiolabeled agonists but not by antagonists in patients with depressive disorders suggests a selective increase in the density of high-affinity conformational state α2ARs, which is indicative of enhanced G protein coupling to the receptor. Importantly, this high-affinity state α2AR upregulation can be normalized with antidepressant treatments. Thus, depressive disorders appear to be associated with increased α2AR sensitivity and responsiveness, which may represent a physiological basis for the putative noradrenergic dysfunction in depressive disorders. In addition, we review changes in some key α2AR accessory proteins in depressive disorders and discuss their potential contribution to α2AR dysfunction.
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Affiliation(s)
- Christopher Cottingham
- Department of Cell, Developmental & Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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Gurguis GN. Psychiatric Disorders. Platelets 2007. [DOI: 10.1016/b978-012369367-9/50806-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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5
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Sastre M, Guimón J, García-Sevilla JA. Relationships between beta- and alpha2-adrenoceptors and G coupling proteins in the human brain: effects of age and suicide. Brain Res 2001; 898:242-55. [PMID: 11306010 DOI: 10.1016/s0006-8993(01)02190-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Interactions between brain alpha2- and beta-adrenoceptors are of interest in physiological (aging) and pathological (major depression) processes involving both receptors. In this study, total beta-adrenoceptors and beta1/2-subtypes were quantitated in postmortem human brains to investigate their relationships with alpha2A-adrenoceptors and specific G proteins during the process of aging and in brains of suicide victims. Analysis of [3H]CGP12177 binding, in the presence of CGP20712A (beta1-antagonist), indicated that the predominant beta-adrenoceptor in the frontal cortex is the beta1-subtype (65-75%). The density of total beta- (r=-0.60, n=44) or beta1-adrenoceptors (r=-0.78, n=22), but not the beta2-subtype, declined with aging (3-80 years). The density of total beta- or beta1-adrenoceptors, but not the beta2-subtype, correlated with the number of alpha2-adrenoceptors quantitated in the same brains with the agonist [3H]UK14304 (r=0.71-0.81) or the antagonist [3H]RX821002 (r=0.61-0.66). Interestingly, the ratios alpha2/beta- or alpha2/beta1-adrenoceptors did not correlate with the age of the subject at death, indicating that the proportion of alpha2/beta-adrenoceptors in brain remains rather constant during the process of aging. The density of beta-adrenoceptors correlated with the immunodensity of G(alpha)s (r=0.55) and Gbeta (r=0.61) proteins, and that of alpha2-adrenoceptors with those of G(alpha)i1/2 (r=0.88) and Gbeta (r=0.65). In brains of suicides, compared to controls, the ratio between alpha2- and beta- or beta1-adrenoceptors (alpha2-full agonist sites/beta-sites) was greater (1.3- to 2.0-fold; P<0.05). The results demonstrate a close interdependence between brain alpha2- and beta-adrenoceptors during aging, and in brains of suicides. The quantitation of the alpha2A/beta-adrenoceptor ratio could represent a relevant neurochemical index in the study of brain pathologies in which both receptors are involved.
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Affiliation(s)
- M Sastre
- Laboratory of Neuropharmacology, Associate Unit of the Institute Cajal/CSIC, Department of Biology, University of the Balearic Islands, Cra. Valldemossa Km 7.5, E-07071, Palma de Mallorca, Spain
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6
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Gurguis GN, Vo SP, Griffith JM, Rush AJ. Platelet alpha2A-adrenoceptor function in major depression: Gi coupling, effects of imipramine and relationship to treatment outcome. Psychiatry Res 1999; 89:73-95. [PMID: 10646827 DOI: 10.1016/s0165-1781(99)00103-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Studies suggest alpha2A-adrenoceptors (alpha(2A)AR) dysregulation in major depressive disorder (MDD). Platelet alpha(2A)ARs exist in high- and low-conformational states that are regulated by Gi protein. Although alpha(2A)AR coupling to Gi protein plays an important role in signal transduction and is modulated by antidepressants, it has not been previously investigated. Alpha2AR density in the high- and low-conformational states, agonist affinity and coupling efficiency were investigated in 27 healthy control subjects, 23 drug-free MDD patients and 16 patients after imipramine treatment using [3H]yohimbine saturation and norepinephrine displacement of [3H]yohimbine binding experiments. Coupling measures were derived from NE-displacement experiments. Patients had significantly higher alpha(2A)AR density, particularly in the high-conformational state, than control subjects. Coupling indices were normal in patients. High pre-treatment agonist affinity to the receptor in the high-conformational state and normal coupling predicted positive treatment outcome. Decreased coupling to Gi predicted a negative treatment outcome. Imipramine induced uncoupling (-11%) and redistribution of receptor density in treatment responders only, but had no effect on alpha(2A)AR coupling or density in treatment non-responders. Increased alpha(2A)AR density may represent a trait marker in MDD. The results provide indirect evidence for abnormal protein kinase A (PKA) and protein kinase C (PKC) in MDD which may be pursued in future investigations.
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MESH Headings
- Adrenergic Uptake Inhibitors/pharmacology
- Adrenergic Uptake Inhibitors/therapeutic use
- Adult
- Antidepressive Agents, Tricyclic/pharmacology
- Antidepressive Agents, Tricyclic/therapeutic use
- Biomarkers/blood
- Blood Platelets/drug effects
- Blood Platelets/metabolism
- Case-Control Studies
- Depressive Disorder, Major/blood
- Depressive Disorder, Major/drug therapy
- Depressive Disorder, Major/psychology
- GTP-Binding Protein alpha Subunits, Gi-Go/blood
- Humans
- Imipramine/pharmacology
- Imipramine/therapeutic use
- Male
- Middle Aged
- Norepinephrine/metabolism
- Protein Binding
- Protein Kinases/metabolism
- Psychiatric Status Rating Scales
- Receptors, Adrenergic, alpha-2/blood
- Receptors, Adrenergic, alpha-2/drug effects
- Treatment Outcome
- Yohimbine/metabolism
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Affiliation(s)
- G N Gurguis
- Mental Health Services, Department of Veterans Affairs Medical Center, Dallas, TX, USA.
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7
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Gurguis GN, Vo SP, Blakeley J, Orsulak PJ, Rush AJ. Characteristics of norepinephrine and clonidine displacement of [3H]yohimbine binding to platelet alpha2-adrenoreceptors in healthy volunteers. Psychiatry Res 1999; 85:305-14. [PMID: 10333382 DOI: 10.1016/s0165-1781(99)00004-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Clonidine's estimates of platelet alpha2-adrenoreceptor (alpha2AR) density are substantially lower than yohimbine's. This discrepancy could have contributed to inconsistent results from studies on the role of alpha2AR in depression. Furthermore, few studies have investigated the relative distribution of alpha2AR between the high- and low-affinity states or their Gi protein coupling. [3H]yohimbine saturable binding to platelet alpha2AR, its displacement by norepinephrine and clonidine, and the effects of Gpp(NH)p on agonist displacement curves were investigated in 11 healthy volunteers. Clonidine estimates of alpha2AR density were close to norepinephrine estimates, and both were strongly correlated. Clonidine's K(L)/K(H) ratio was lower than norepinephrine's, consistent with its partial agonist nature. Norepinephrine and clonidine displacement curves revealed two affinity states. Gpp(NH)p induced a significant rightward shift to a single low-affinity state. When used in combination with a specific antagonist, clonidine's estimates of alpha2AR density were similar to those of norepinephrine's, and both were higher than previously reported, when clonidine was used alone. Re-evaluation of previous studies on alpha2AR in depression using clonidine is needed. The combined use of antagonist-saturation and agonist-displacement experiments to examine possible dysregulation in alpha2AR coupling to Gi protein in psychiatric disorders is recommended.
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Affiliation(s)
- G N Gurguis
- Department of Veterans Affairs Medical Center (116A), Dallas, TX 75216, USA.
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8
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Maes M, Van Gastel A, Delmeire L, Meltzer HY. Decreased platelet alpha-2 adrenoceptor density in major depression: effects of tricyclic antidepressants and fluoxetine. Biol Psychiatry 1999; 45:278-84. [PMID: 10023502 DOI: 10.1016/s0006-3223(98)00002-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND It has been suggested that major depression is accompanied by a subsensitivity of central alpha 2-adrenoceptors (alpha 2-ARs) and, consequently, by an impaired negative feedback on the presynaptic catecholaminergic neuron, which, in turn, may induce a disinhibition of noradrenergic output and norepinephrine release in response to any activation. METHODS The maximum number of platelet binding sites (Bmax) and their affinity for [3H]-rauwolscine, a selective alpha 2-AR antagonist, were measured in unmedicated and medicated major depressed patients and in normal volunteers. Specific binding was defined as that inhibited by idazoxan, another alpha 2-AR antagonist. RESULTS Unmedicated major depressed patients had significantly decreased platelet [3H]-rauwolscine binding Bmax values compared to normal volunteers. [3H]-rauwolscine binding Kd values did not differ significantly between unmedicated major depressed patients and normal controls. [3H]-rauwolscine binding Kd values were significantly higher in depressed patients treated with tricyclic antidepressants than in unmedicated patients. Subchronic treatment with fluoxetine did not significantly alter either [3H]-rauwolscine binding Bmax or Kd values. [3H]-rauwolscine binding Bmax values were significantly greater in men than in women. CONCLUSIONS The results suggest that i) major depression is accompanied by decreased platelet alpha 2-AR density; and that ii) subchronic treatment with tricyclic antidepressants, but not fluoxetine, results in a decreased affinity of rauwolscine for platelet alpha 2-ARs.
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Affiliation(s)
- M Maes
- Clinical Research Center for Mental Health, Antwerp, Belgium
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9
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Rosel P, Arranz B, Vallejo J, Alvarez P, Menchon JM, Palencia T, Navarro MA. Altered [3H]imipramine and 5-HT2 but not [3H]paroxetine binding sites in platelets from depressed patients. J Affect Disord 1999; 52:225-33. [PMID: 10357037 DOI: 10.1016/s0165-0327(98)00030-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
BACKGROUND Serotonergic system alterations were studied in 51 depressed patients classified according to DSM-III-R criteria for major depression with melancholia compared to 31 healthy controls. METHOD [3H]Imipramine and [3H]paroxetine binding sites and the 5HT2 receptor were simultaneously determined in blood platelet membranes. RESULTS A significantly lower maximum binding in [3H]imipramine binding was observed in depressed patients compared to controls (1134+/-74 vs. 1712+/-106 fmol/mg protein, P<0.0001) without changes in the equilibrium dissociation constant (1.10+0.05 vs. 1.25-/+0.09 nM). [3H]Paroxetine binding did not differ between the two groups (Bmax, 1441+/-55 vs. 1280+/-81 fmol/mg protein; Kd, 0.060+/-0.002 vs. 0.062+/-0.002 nM). The K(d) value of 5HT2 binding was lower in depressed patients than controls (0.95+/-0.04 vs. 1.15+/-0.09 nM, P<0.039) without changes in maximum binding (140+/-11 vs. 127+/-14 fmol/mg protein). CONCLUSIONS Taken together, these results suggest that [3H]imipramine and 5HT2 receptors may be good biological markers for serotonergic dysfunction in depressive disorders.
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MESH Headings
- Adult
- Aged
- Antidepressive Agents, Second-Generation/blood
- Antidepressive Agents, Second-Generation/pharmacokinetics
- Antidepressive Agents, Second-Generation/therapeutic use
- Antidepressive Agents, Tricyclic/blood
- Antidepressive Agents, Tricyclic/pharmacokinetics
- Antidepressive Agents, Tricyclic/therapeutic use
- Binding Sites/drug effects
- Biomarkers
- Cell Membrane/metabolism
- Depressive Disorder, Major/blood
- Depressive Disorder, Major/drug therapy
- Depressive Disorder, Major/psychology
- Female
- Humans
- Imipramine/blood
- Imipramine/pharmacokinetics
- Imipramine/therapeutic use
- Male
- Middle Aged
- Paroxetine/blood
- Paroxetine/pharmacology
- Paroxetine/therapeutic use
- Receptors, Serotonin/blood
- Receptors, Serotonin/metabolism
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Affiliation(s)
- P Rosel
- Department of Biochemistry, Hospitalet de Llobregat, Barcelona, Spain
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10
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Mongeau R, Blier P, de Montigny C. The serotonergic and noradrenergic systems of the hippocampus: their interactions and the effects of antidepressant treatments. BRAIN RESEARCH. BRAIN RESEARCH REVIEWS 1997; 23:145-95. [PMID: 9164669 DOI: 10.1016/s0165-0173(96)00017-3] [Citation(s) in RCA: 291] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Previous reviews have well illustrated how antidepressant treatments can differentially alter several neurotransmitter systems in various brain areas. This review focuses on the effects of distinct classes of antidepressant treatments on the serotonergic and the noradrenergic systems of the hippocampus, which is one of the brain limbic areas thought to be relevant in depression: it illustrates the complexity of action of these treatments in a single brain area. First, the basic elements (receptors, second messengers, ion channels, ...) of the serotonergic and noradrenergic systems of the hippocampus are revisited and compared. Second, the extensive interactions occurring between the serotonergic and the noradrenergic systems of the brain are described. Finally, issues concerning the short- and long-term effects of antidepressant treatments on these systems are broadly discussed. Although there are some contradictions, the bulk of data suggests that antidepressant treatments work in the hippocampus by increasing and decreasing, respectively, serotonergic and noradrenergic neurotransmission. This hypothesis is discussed in the context of the purported function of the hippocampus in the formation of memory traces and emotion-related behaviors.
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Affiliation(s)
- R Mongeau
- Department of Psychiatry, McGill University, Montréal, Québec, Canada
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11
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Bakish D, Cavazzoni P, Chudzik J, Ravindran A, Hrdina PD. Effects of selective serotonin reuptake inhibitors on platelet serotonin parameters in major depressive disorder. Biol Psychiatry 1997; 41:184-90. [PMID: 9018388 DOI: 10.1016/s0006-3223(96)00040-6] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The effects of treatment with serotonin (5-HT) reuptake inhibitors on platelet 5-HT2 receptors, 5-HT reuptake sites an 5-HT uptake were studied in a double-blind trial comparing two selective serotonin reuptake inhibitors (SSRI), paroxetine, and fluoxetine, for the treatment of major depression. Hamilton Depression Rating Scale (HAM-D) scores and platelet 5-HT parameters were determined in 21 depressed patients at baseline, after 4 and 8 weeks of treatment, and were compared to 21 healthy controls. Antidepressant treatment did not significantly alter the density of 5-HT reuptake sites, labelled with [3H]paroxetine, or 5-HT2 receptors, labelled with [3H]LSD. However, a strong correlation was observed between the HAM-D suicidality item and 5-HT2 receptor density at baseline. A marked increase in platelet 5-HT2 receptors at baseline was observed in suicidal depressed patients compared to those with no suicidal ideation and healthy controls. Changes in [3H]paroxetine Bmax and in [3H]5-HT uptake significantly correlated with change in HAM-D score at 4 and 8 weeks respectively. These results confirm previous reports of an association between suicidality and platelet 5-HT2 receptor upregulation. Our data also lends support to the use of platelet 5-HT parameters as indicators of antidepressant efficacy, particularly in suicidal depressed patients.
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Affiliation(s)
- D Bakish
- Department of Psychiatry, University of Ottawa, Ontario, Canada
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12
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Piletz JE, Halaris A, Nelson J, Qu Y, Bari M. Platelet I1-imidazoline binding sites are elevated in depression but not generalized anxiety disorder. J Psychiatr Res 1996; 30:147-68. [PMID: 8884655 DOI: 10.1016/0022-3956(96)00005-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Depressed patients have been reported to have a higher than normal density of platelet binding sites for 3H-clonidine, an alpha 2-adrenoceptor agonist. Paradoxically, other studies using 3H-alpha 2, antagonists have found no differences from controls. Because 3H-clonidine interacts with platelet alpha 2-adrenoceptors to form G-protein complexes, whereas 3H-alpha 2-antagonists bind with uncoupled receptors, an elevation in G-protein coupling might explain this paradox. Another possibility is that depression might be associated with increased non-adrenergic I1-imidazoline binding sites, which are also clonidine sensitive. To distinguish these possibilities, we utilized p125I-clonidine to measure density (Bmax) and affinity (KD) of platelet G-protein coupled alpha 2-adrenoceptors as well as platelet I1 binding sites, and compared diagnostic groups of major depressive disorder (MDD), generalized anxiety disorder (GAD) and healthy subjects. Specific inhibition of binding by norepinephrine (NE = 10 microM) was used to selectively quantify alpha 2-adrenoceptors, whereas inhibition by 10 microM moxonidine (a > 100-fold selective I1 ligand) quantified I1 binding sites under a NE mask. I1 sites were found to be markedly elevated by, on average, +136% in MDD patients (p = .0007), whereas there was only a marginal increase in alpha 2-adrenoceptor Bmax values in MDD patients (p = .08; GAD and healthy subjects did not differ). Treatment of MDD patients for 6-8 weeks with desipramine downregulated I1 sites as well as alpha 2-adrenoceptors. Positive correlations were also noted for both sites: (a) between Bmax values and the severity of depression (using the Hamilton Depression Rating Scale); and (b) between end-of-treatment plasma desipramine concentrations and the extent of downregulation in Bmax values when subject groups were pooled. None of the binding parameters was associated with plasma catecholamine concentrations. The results suggest that an increased density of platelet I1 binding sites may partially explain the utility of radiolabeled clonidine as a potential biological marker for depressive illness, although an additional increase in G-protein coupling cannot be excluded.
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Affiliation(s)
- J E Piletz
- Department of Psychiatry, University of Mississippi Medical Center, Jackson 39216-4505, USA
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13
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Rosel-Soria P, Vallejo J, Oros M, Serrallonga J, Menchon JM, Navarro MA. Changes in platelet 3-H-imipramine binding: influences of protein concentration of varying proportions of cytosol or intact platelets and displacing agents used. Biol Psychiatry 1995; 38:464-70. [PMID: 8672607 DOI: 10.1016/0006-3223(94)00380-l] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Platelet 3-H-imipramine binding exhibits considerable variation, both interindividually and between several groups. The aim of this study was to measure 3-H-imipramine binding, simultaneously in platelet membranes vs. intact platelets vs. cytosol or intracytosolic protein in order to determine their effect on Bmax and Kd values. 3-H-imipramine binding was carried out at different protein concentrations. Our results indicate that the affinity constant is heavily influenced by the presence of cytosol and intact platelets in membrane preparations. Finally, we demonstrate a negative correlation between Bmax and protein concentration. Only perfect analytical conditions will allow platelet 3-H-imipramine binding to be a biological marker for affective disorders.
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Affiliation(s)
- P Rosel-Soria
- Hormone Unit, Hospital Princeps d'Espanya, Barcelona, Spain
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14
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Abstract
Although it has been suggested that decreased platelet imipramine binding may be a putative biological marker of depressive illness, a number of studies have not confirmed this finding, including a recent multicenter investigation by the World Health Organization (Mellerup and Langer 1990). We performed a meta-analysis of published reports on imipramine binding in groups of depressed and healthy control subjects and found that there was a highly significant decrease in Bmax (maximal binding) values in the depressed subject groups, which was even greater among those who had been free of medication for 4 weeks at the time of investigation. This finding remained highly significant even when only high affinity binding studies (Kd < 1 nmol/L) were considered, although the absolute size of this decrease was smaller.
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Affiliation(s)
- P M Ellis
- Department of Psychological Medicine, Wellington School of Medicine, New Zealand
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15
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Halbreich U, Piletz JE, Carson S, Halaris A, Rojansky N. Increased imidazoline and alpha 2 adrenergic binding in platelets of women with dysphoric premenstrual syndromes. Biol Psychiatry 1993; 34:676-86. [PMID: 7904832 DOI: 10.1016/0006-3223(93)90040-k] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
An association between dysphoric premenstrual syndromes (PMS) and a lifetime history of major depressive disorders has previously been documented. Other studies have demonstrated an increase in the binding of radiolabeled imidazoline compounds to platelets of depressed patients. Clonidine and related imidazoline compounds interact with alpha 2 adrenoceptors to inhibit neuronal noradrenergic activity and in higher concentrations, they stimulate noradrenergic activity through their interaction with imidazoline receptors. Here we report increased 3H para-aminoclonidine binding to high affinity alpha 2 adrenoceptor sites as well as to nonadrenergic imidazoline binding sites in platelets of women with dysphoric PMS. This higher binding was most pronounced during the late-luteal-symptomatic phase of the menstrual cycle and, to a lesser degree, during the non-symptomatic mid-follicular phase. Binding to the imidazoline site distinguished women with dysphoric PMS from women with no such symptoms, was highly positively correlated with the severity of symptoms, and was negatively correlated with plasma levels of progesterone. These findings suggest that platelet imidazoline binding sites might be a biological marker for dysphoric states in PMS or for the vulnerability to develop them. These findings also point to a possible biological link between dysphoric PMS and major depressive disorders.
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Affiliation(s)
- U Halbreich
- Department of Psychiatry, State University of New York at Buffalo 14215
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16
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Danilenko KV, Putilov AA. Diurnal and seasonal variations in cortisol, prolactin, TSH and thyroid hormones in women with and without seasonal affective disorder. ACTA ACUST UNITED AC 1993. [DOI: 10.1080/09291019309360211] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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17
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Karege F, Bovier P, Widmer J, Gaillard JM, Tissot R. Platelet membrane alpha 2-adrenergic receptors in depression. Psychiatry Res 1992; 43:243-52. [PMID: 1359596 DOI: 10.1016/0165-1781(92)90057-a] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The platelet membrane was used as a model system to examine alpha 2-adrenergic receptors in 30 depressed patients and 30 healthy control subjects. The number of binding sites and their affinity for 3H-UK 14304 (5-bromo-6-(2-imidazoline-2-ylamino)-quinoxaline), a potent, highly selective alpha 2-adrenergic receptor agonist, was measured. Plasma magnesium and free 3-methoxy-4-hydroxyphenylglycol (MHPG) concentrations were assayed in the same sample. A decreased agonist-receptor affinity was found in depressed patients, whereas receptor density was not significantly altered compared with that in control subjects. In bipolar depressed and dysthymic patients, there was a tendency toward a higher density of alpha 2-adrenergic receptors. This trend was not apparent in unipolar, recurrent depressed subjects. Moreover, a positive correlation between Bmax and Kd values was observed in patients but not in control subjects--a finding that suggests that a compensatory phenomenon occurs in depression. After the patients were treated with antidepressant drugs, an increased affinity (decrease in Kd) was observed, together with a decrease in binding sites. Plasma magnesium concentrations were higher in drug-free depressed patients than in control subjects. In addition, magnesium concentrations were negatively correlated with the density of alpha 2-adrenergic receptor binding sites in depressed patients, both before and during treatment. Lastly, a trend toward a negative correlation between plasma MHPG concentration and the number of binding sites was also observed. These results suggest a complex multifactorial regulation of alpha 2-adrenergic receptors, which are probably hyposensitive in depressive syndromes.
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Affiliation(s)
- F Karege
- Division of Biochemistry, Institutions Universitaires de Psychiatrie, Geneva Medical School, Switzerland
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18
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Ellis PM, Beeston R, McIntosh CJ, Salmond CE, Cooke RR. Platelet 3H-imipramine binding during recovery from depression. Acta Psychiatr Scand 1992; 86:108-12. [PMID: 1529732 DOI: 10.1111/j.1600-0447.1992.tb03237.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Decreased binding of tritiated imipramine to platelets has been considered to be a potential biological marker of depression. However, it has been unclear how binding values alter during treatment and recovery. This study investigated imipramine binding parameters and depressive symptoms in 25 patients suffering from major depression at entry to the study and 1, 3 and 6 months later. Although the initial Bmax values were significantly lower in the depressed patients than in healthy subjects, it was not possible to establish a clear relationship between recovery from depression and Bmax. The power of this study to detect an effect of at least 10% of the variance in Bmax due to factors related to recovery from depression was 0.78.
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Affiliation(s)
- P M Ellis
- Department of Psychological Medicine, Wellington School of Medicine, University of Otago, New Zealand
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Szádóczky E, Falus A, Németh A, Teszéri G, Moussong-Kovács E. Effect of phototherapy on 3H-imipramine binding sites in patients with SAD, non-SAD and in healthy controls. J Affect Disord 1991; 22:179-84. [PMID: 1658102 DOI: 10.1016/0165-0327(91)90063-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The effect of incandescent light treatment on the density of 3H-imipramine binding sites (Bmax) was investigated in 17 patients with seasonal affective disorder, in eight patients with non-seasonal depression and in six healthy volunteers. A significant increase in mean Bmax value parallel to a marked improvement of the depressive symptoms was found only in patients with SAD. No effect was observed either on mean Bmax value or on clinical symptoms in patients with non-SAD and on mean Bmax value in healthy volunteers.
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Affiliation(s)
- E Szádóczky
- Postgraduate Medical School Department of Psychiatry and Clinical Psychology, National Institute for Nervous and Mental Diseases, Budapest, Hungary
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Piletz JE, Andorn AC, Unnerstall JR, Halaris A. Binding of [3H]-p-aminoclonidine to alpha 2-adrenoceptor states plus a non-adrenergic site on human platelet plasma membranes. Biochem Pharmacol 1991; 42:569-84. [PMID: 1677571 DOI: 10.1016/0006-2952(91)90320-5] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Characterization of the binding of [3H]p-aminoclonidine ([3H]PAC) to purified plasma membranes from human platelets has revealed multiple binding sites. [3H]PAC identified site-1 in the picomolar affinity range (site-1 KD estimates ranged from 13 to 94 pM). Site-1 displayed a rank order of competition by various compounds for [3H]PAC, indicative of an alpha 2-adrenoceptor, and was sensitive to 0.1 mM GTP. [3H]PAC also identified a second site with nanomolar affinity (site-2 KD estimates ranged from 0.7 to 1.7 nM). In the presence of 0.1 mM GTP, site-2 was not diminished significantly. Also in contrast to site-1, site-2 displayed low affinity for yohimbine (YOH), (-)-epinephrine and (-)-norepinephrine (NE). Therefore, site-2 could not be an active alpha 2-adrenoceptor; instead it had properties similar to a previously reported imidazoline-preferring binding site. A third site (site-3) bound [3H]PAC with a KD for site-3 of 26.6 +/- 10.0 nM (SD). Site-3 had a rank order of competition by various compounds for 5 nM [3H]yohimbine ([3H]YOH) binding which was indicative of an alpha 2-adrenoceptor. (-)-NE competed for 5 nM [3H]YOH binding at two sites: site-1 Ki = 32 pM, site-3 Ki = 239 nM. Treatment with 0.1 mM GTP completely removed site-1 and transferred the competitive binding of (-)-NE to low affinity (Ki = 437 nM). Thus, site-3 appears to be a free alpha 2-adrenoceptor. Bmax estimates for untreated membranes, derived from simultaneous multi-experiment curve-fitting analyses, were site-1 = 36 +/- 29 fmol/mg plasma membrane protein, site-2 = 95 +/- 34 fmol/mg and site-3 = 154 +/- 35 fmol/mg. We are the first to report a site for [3H]PAC binding on platelets (site-2) with properties uncharacteristic of an adrenoceptor. This observation appears to be due to our use of purified plasma membrane and low ionic strength buffer. These studies relate to reports of increased binding of [3H]PAC to platelets from depressed patients.
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Affiliation(s)
- J E Piletz
- Department of Psychiatry, Case Western Reserve University, School of Medicine, Cleveland, Ohio
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Piletz JE, Sarasua M, Chotani M, Saran A, Halaris A. Relationship between membrane fluidity and adrenoceptor binding in depression. Psychiatry Res 1991; 38:1-12. [PMID: 1682966 DOI: 10.1016/0165-1781(91)90047-s] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Membrane fluidity and adrenergic receptor binding were studied in platelets of depressed patients before and during treatment with desmethylimipramine to investigate the relationship between the alpha 2-adrenergic receptor and its membrane environment in depression. Most samples came from a previous study in which we observed higher 3H-para-aminoclonidine (3H-PAC) binding in platelets from depressed patients compared to healthy subjects. Fluidity was measured by steady state diphenylhexatriene (DPH) anisotropy in both purified plasma membranes and in intracellular membrane preparations from platelets. No differences were observed in DPH membrane fluidity, per se, indicating that fluidity changes probably do not underlie either the increased alpha 2-adrenergic receptor binding in depression or the normalization of binding during treatment. However, lower intracellular membrane fluidity was correlated with higher binding to 3H-PAC site-1 in healthy subjects, but not in depressed patients. Thus, during depression there may be a disruption in the normal relationship between the adrenergic receptor and its membrane environment.
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Affiliation(s)
- J E Piletz
- Dept. of Psychiatry, MetroHealth Medical Center, Cleveland, OH 44109
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Ellis PM, Mellsop GW, Beeston R, Cooke RR. Platelet tritiated imipramine binding in patients suffering from mania. J Affect Disord 1991; 22:105-10. [PMID: 1655851 DOI: 10.1016/0165-0327(91)90043-r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Platelet imipramine binding was measured in 16 patients suffering from DSM-IIIR mania and compared with binding values reported in depressed and healthy control subjects recruited in a parallel study (Ellis et al., 1990). Binding levels in the manic group did not differ from control values, but were higher than in the depressed group. Within the manic group, binding did not differ with severity of illness or the presence of depressive symptoms but there was a trend to lower values (comparable to those in the depressed group) with increasing duration of illness. This raises the possibility that changes in imipramine binding in depression and mania may be similar, consistent with the permissive hypothesis of serotonin function.
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Affiliation(s)
- P M Ellis
- Department of Psychological Medicine, Wellington School of Medicine, New Zealand
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Abstract
Platelet alpha 2-adrenergic receptor binding and prostaglandin responsivity were measured in depressed patients. Depressed patients had significantly higher platelet 3H-dihydroergocryptine (3H-DHE) binding values than controls. Depressed patients also showed significantly reduced prostaglandin E1-stimulated cyclic adenosine 3',5'-monophosphate (cAMP) production and significantly decreased % inhibition of cAMP production by norepinephrine. These results support the suggestion that there may be a dissociation between alpha 2-adrenergic receptor binding and responsivity in depression. There were no significant correlations between platelet adrenergic variables and other indices of noradrenergic function. However, there was a significant correlation between 3H-DHE binding values and basal plasma levels of cortisol.
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Affiliation(s)
- A Roy
- National Institute of Mental Health, Bethesda, MD
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