Pharmacological Characterization of an Opioid Receptor in the Ciliate Tetrahymena

Chiesa, Ricardo; Silva, Walter I.; Renaud, Fernando L.

doi:10.1111/j.1550-7408.1993.tb04478.x

Cited by 31 publications

(12 citation statements)

References 20 publications

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“…Wu et al (1997) [16] demonstrated that the drug was ineffective to inhibit the immobilizing effect-induced by an opioid in the organism. Josefsson and Johansson (1979) [17] demonstrated a naloxone-reversible opioid effect on pinocytosis in Amoeba, and similar observation was made by Chiesa et al (1993) [18], as well as by Salaman et al (1990) [19], who studied phagocytosis in Tetrahymena. In contrast to these data, we studied the opioid receptor-ligand relation in accumulation or avoidance of Paramecium.…”

Section: Discussionmentioning

confidence: 54%

Paramecium caudatum Avoids from Naloxone

Karami

Moezzi²,

Kazemi³

et al. 2013

AJIDM

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Protozoa aggregate to or avoid from chemical substances. We aimed to show the significance of nitric oxide (NO) in the performance of the eukaryotes to misuse drug exposure. The micro-organism Paramecium caudatum was collected from natural sources and properly isolated by repeatedly sub-cultivation in hay infusion. Number of cells per 1ml of pure medium culture was counted using Sedgwick-Rafter cell chamber. Doses of naloxone (0.05-0.4µg/µl) solely or jointly with the NO agents were infused into the chamber. Cell response was recorded after drug infusion with intervals (0-180 sec). Negative control received distilled water (1µl) instead of naloxone (legend 0). Along with, the Ca channels or cGMP pathway was banded to discuss the mechanism. According to the results, the Paramecia showed negative chemo-taxis to the naloxone, the response which is comparable with signs of withdrawal from abused drugs. This response was potentiated by activation of NO system, but, reversed after usage of the system blocker. The inhibition of Ca channels or cGMP signaling pathway markedly enhanced the avoidance. In conclusion, this study may clearly contribute the signal molecule NO in the dependence of the eukaryotes on sedative misuse drugs.

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Section: Discussionmentioning

confidence: 54%

Paramecium caudatum Avoids from Naloxone

Karami

Moezzi²,

Kazemi³

et al. 2013

AJIDM

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“…Tetrahymena opioids inhibit phagocytosis of Tetrahymena by a naloxonereversible mechanism [45]. The opioid receptors of Tetrahymena are more sensitive to beta-endorphin and most sensitive to morphine [46], which points to the mu-likeness in some pharmacological characters. Chronic treatment with an opioid causes tolerance [47].…”

Section: Peptide Hormonesmentioning

confidence: 99%

“…Unicellulars synthesize, store, and secrete amino acid-and polypeptide-type hormones characteristic to multicellular animals (mammals) [4][5][6][7][8][9][10][11][12][13][14]. In addition, the cells have mammalian receptor-like structures in the plasma membrane, which bind these hormones and the cells react to them [15][16][17][18][19], as they have signal transducer pathways [20][21][22][23]. Many cell functions of the unicellular ciliate Tetrahymena are influenced by the hormones and their effect sometimes seems to be specific [19].…”

mentioning

confidence: 99%

Is there a hormonal regulation of phagocytosis at unicellular and multicellular levels? A critical review

Csaba

2017

AMicr

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Phagocytosis is an ancient cell function, which is similar at unicellular and multicellular levels. Unicells synthesize, store, and secrete multicellular (mammalian) hormones, which influence their phagocytosis. Amino acid hormones, such as histamine, serotonin, epinephrine, and melatonin stimulate phagocytosis, whereas peptide hormones, such as adrenocorticotropic hormone (ACTH), insulin, opioids, arginine vasopressin, and atrial natriuretic peptide decreased it, independently on their chemical structure or function in multicellulars. Macrophage phagocytosis of multicellulars is also stimulated by amino acid hormones, such as histamine, epinephrine, melatonin, and thyroid hormones, however, the effect of peptide hormones is not uniform: prolactin, insulin, glucagon, somatostatin, and leptin have positive effects, whereas ACTH, human chorionic gonadotropin, opioids, and ghrelin have negative ones. Steroid hormones, such as estrogen, hydrocortisone, and dexamethasone are stimulating macrophage phagocytosis, whereas progesterone, aldosterone, and testosterone are depressing it. Considering the data and observations there is not a specific phagocytosis hormone, or a hormonal regulation of phagocytosis neither unicellular, nor multicellular level, however, hormones having specific functions in multicellulars also influence phagocytosis at both levels universally (in unicellulars) or individually (in macrophages). Nevertheless, the hormonal influence cannot be neglected, as phagocytosis (as a function) is rather sensitive to minute dose of hormones and endocrine disruptors. The hormonal influence of phagocytosis by macrophages can be deduced to the events at unicellular level.

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“…[1][2][3][4][5][6] Some of these hormones have receptors which are similar to the mammalian ones [7][8][9][10][11][12] and the reaction of Tetrahymena provoked by the hormones is also similar to the reaction of mammalian cells. For example: insulin has such receptors [7][8][9] and after binding, the signal transduction is similar to the mammalian one.…”

Section: Introductionmentioning

confidence: 99%

Effect of femtomolar concentrations of hormones on insulin binding by Tetrahymena, as a function of time

Csaba

Kovács

Pállinger

2007

Cell Biochemistry & Function

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The unicellular ciliate Tetrahymena, contains and binds hormones, characteristic of vertebrates. Earlier experiments demonstrated the effect of extremely low concentrations of hormones. In the present experiments, the effect of various hormones (endorphin, serotonin, histamine, insulin and epidermal growth factor [EGF]) in 10(-15) M, or oxytocin, gonadotropin at 0.001 IU concentrations) on the binding of FITC-insulin was studied by using flow cytometry and confocal microscopy, after 1, 5, 15, 30 and 60 min. Six of the seven hormones promptly decreased the cells' hormone binding capacity, the exception being EGF, and in four cases (endorphin, serotonin, insulin and oxytocin) the reduction was enormous. The decreased binding was durable. However, in the case of endorphin and oxytocin after 30 min, and in the case of serotonin after 60 min the binding returned to the control level. In the case of oxytocin after 60 min, binding significantly surpassed the control level. Histamine returned to the control level after 15 min, but after that the binding became even lower. EGF provoked special behaviour: it increased hormone binding after 30 and 60 min. The results call attention to the extreme sensitivity of Tetrahymena receptors to hormonal inductions and to its quick response ability.

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Pharmacological Characterization of an Opioid Receptor in the Ciliate Tetrahymena

Cited by 31 publications

References 20 publications

<i>Paramecium caudatum</i> Avoids from Naloxone

<i>Paramecium caudatum</i> Avoids from Naloxone

Is there a hormonal regulation of phagocytosis at unicellular and multicellular levels? A critical review

Effect of femtomolar concentrations of hormones on insulin binding by Tetrahymena, as a function of time

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