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Finkielman S. [The most uninspired intuition of an erudite]. Medicina (B Aires) 2001; 61:105-8. [PMID: 11265609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
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García SI, Alvarez AL, Porto PI, Garfunkel VM, Finkielman S, Pirola CJ. Antisense inhibition of thyrotropin-releasing hormone reduces arterial blood pressure in spontaneously hypertensive rats. Hypertension 2001; 37:365-70. [PMID: 11230301 DOI: 10.1161/01.hyp.37.2.365] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Thyrotropin-releasing hormone (TRH) plays an important role in central cardiovascular regulation. Recently, we described that the TRH precursor gene overexpression induces hypertension in the normal rat. In addition, we published that spontaneously hypertensive rats (SHR) have central extrahypothalamic TRH hyperactivity with increased TRH synthesis and release and an elevated TRH receptor number. In the present study, we report that intracerebroventricular antisense (AS) treatment with a phosphorothioate oligonucleotide against the TRH precursor gene significantly diminished up to 72 hours and in a dose-dependent manner the increased diencephalic TRH content, whereas normalized systolic blood pressure (SABP) was present in the SHR compared with Wistar-Kyoto (WKY) rats. Although basal thyrotropin was higher in SHR compared with WKY rats and this difference disappeared after antisense treatment, no differences were observed in plasma T4 or T3 between strains with or without AS treatment, indicating that the effect of the AS on SABP was independent of the thyroid status. Because the encephalic renin-angiotensin system seems to be crucial in the development and/or maintenance of hypertension in SHR, we investigated the effect of antisense inhibition of TRH on that system and found that TRH antisense treatment significantly diminished the elevated diencephalic angiotensin II (Ang II) content in the SHR without any effect in control animals, suggesting that the Ang II system is involved in the TRH cardiovascular effects. To summarize, the central TRH system seems to be involved in the etiopathogenesis of hypertension in this model of essential hypertension.
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García SI, Porto PI, Martinez VN, Alvarez AL, Finkielman S, Pirola CJ. Expression of TRH and TRH-like peptides in a human glioblastoma-astrocytoma cell line (U-373-MG). J Endocrinol 2000; 166:697-703. [PMID: 10974663 DOI: 10.1677/joe.0.1660697] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The human glioblastoma-astrocytoma cell line U-373-MG shows morphological features typical of its neuroectodermal origin. Cells showed positive immunostaining for the glial fibrillary acidic protein. We used this cell culture for studying the putative production of TRH and TRH-related peptides. In a cell extract and conditioned medium, cation and anion exchange chromatography and HPLC revealed the presence of TRH and acidic TRH-like peptides which were identified, at least in part, as pGlu-Glu-ProNH(2). These findings demonstrated that U-373-MG cells are able to produce and release these peptides. Further evidence of TRH synthesis was obtained by amplification using RT-PCR of a 396 bp fragment that corresponds to the TRH precursor mRNA. Our results therefore suggest that the U-373-MG cell line may be a useful model for studying the regulation of TRH and TRH-related peptide production and the interaction of these peptides with other classical neurotransmitter systems. In fact, pilocarpine (a muscarinic cholinergic agonist) enhanced and nicotine (a nicotinic cholinergic agonist) decreased TRH and TRH-related compound production by this cell line. These data also point out that glia may produce substances with neuromodulatory action.
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Finkielman S. [Addio del passato. What kind of memory is musical memory?]. Medicina (B Aires) 2000; 59:505-6. [PMID: 10684176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
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5
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Garcia SI, Clemens TL, Fagin JA, Finkielman S, Pirola CJ. Parathyroid hormone-related protein expression in vascular smooth muscle of spontaneously hypertensive rats: evidence for lack of response to angiotensin II. J Hypertens 1998; 16:1467-74. [PMID: 9814617 DOI: 10.1097/00004872-199816100-00010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE We studied the expression of parathyroid hormone (PTH)-related protein in vascular smooth muscle cells of spontaneously hypertensive rats (SHR) using Wistar-Kyoto (WKY) and Sprague-Dawley rats as normotensive controls. METHODS Aortae from 4- and 18-week-old SHR versus age-matched WKY and Sprague-Dawley rats were excised to obtain total RNA or smooth muscle cells. The cells were subcultured in Dulbecco's Modified Eagle's Medium containing 10% fetal calf serum, then serum-deprived for 72 h and stimulated with 0.1 micromol/I angiotensin II. PTH-related protein, c-myc and angiotensin II type qa receptor (AT1aR) messenger (m)RNA levels were measured by Northern blot, using total RNA extracted by phenol/chloroform. The effects of PTH-related protein(1-34)NH2 intravenous injections on arterial blood pressure and the heart rate were studied in anesthetized SHR and WKY rats. RESULTS The Northern blots showed a significantly higher abundance of PTH-related protein mRNA in aortae of SHR versus WKY rats in the prehypertensive state but no significant difference in adult animals. In cultured aortic smooth muscle cells, angiotensin II induced a four- to sixfold increase in PTH-related protein mRNA levels in smooth muscle cells from normotensive animals, but failed to elicit a significant response in smooth muscle cells derived from SHR in either the prehypertensive or the hypertensive state. This lack of response to angiotensin II in SHR smooth muscle cells was not due to decreased expression or responsiveness of the AT1aR, since SHR smooth muscle cells had more AT1aR mRNA than Sprague-Dawley smooth muscle cells, and angiotensin II-induced activation of c-myc was faster and greater in smooth muscle cells derived from 4- or 18-week-old SHR than in Sprague-Dawley smooth muscle cells. In contrast, PTH-related protein(1-34)NH2 induced a long-lasting dose-dependent hypotensive and tachycardic response in both SHR and WKY rats, indicating that SHR retained responsiveness to the vasodilator. CONCLUSIONS PTH-related protein gene expression in response to angiotensin II is impaired in SHR arteries. A deficiency in this potent local vasodilator may contribute to the development and/or maintenance of arterial hypertension in this model.
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MESH Headings
- Angiotensin II/pharmacology
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/metabolism
- Blotting, Northern
- Hemodynamics/drug effects
- Hypertension/metabolism
- Injections, Intravenous
- Male
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Parathyroid Hormone/metabolism
- Parathyroid Hormone-Related Protein
- Proteins/genetics
- Proteins/metabolism
- Proto-Oncogene Proteins c-myc/genetics
- Proto-Oncogene Proteins c-myc/metabolism
- RNA, Messenger/metabolism
- Rats
- Rats, Inbred SHR
- Rats, Inbred WKY
- Rats, Sprague-Dawley
- Receptor, Angiotensin, Type 1
- Receptor, Angiotensin, Type 2
- Receptors, Angiotensin/genetics
- Receptors, Angiotensin/metabolism
- Vasoconstrictor Agents/pharmacology
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6
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Finkielman S. [Difficult for the physician]. Medicina (B Aires) 1998; 58:327-8. [PMID: 9713109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
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7
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García SI, Porto PI, Alvarez AL, Martinez VN, Shaurli D, Finkielman S, Pirola CJ. Central overexpression of the TRH precursor gene induces hypertension in rats: antisense reversal. Hypertension 1997; 30:759-66. [PMID: 9323019 DOI: 10.1161/01.hyp.30.3.759] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Extrahypothalamic TRH participates in cardiovascular regulation and spontaneous hypertension of the rat. To investigate whether an increase in central TRH activity produces hypertension we studied the effect of the preTRH overproduction induced by I.C.V. transfection with a naked eukaryotic expression plasmid vector which encodes preTRH (pCMV-TRH). Northern blot analysis and RT-PCR showed that pCMV-TRH was transcribed in vitro and in vivo. At 24, 48, and 72 hours, pCMV-TRH (100 microg) in a significant and dose-dependent manner increased 37%, 84%, and 49%, respectively, the diencephalic TRH content and SABP (42+/-3, 50+/-2, and 22+/-2 mm Hg, respectively) with respect to the vector without the preTRH cDNA insert (V[TRH(-)]) as measured by RIA and the plethysmographic method, respectively, in awake animals. In addition, using immunohistochemistry we found that the increase of TRH was produced in circumventricular areas where the tripeptide is normally located. To further analyze the specificity of these effects we studied the actions of 23-mer sense (S), antisense (AS), and 3'self-stabilized sense (Ss) and antisense (ASs) phosphorothioate oligonucleotides against the initiation codon region. Only ASs inhibited the increase of TRH content and SABP induced by pCMV-TRH treatment. In addition, pCMV-TRH-induced hypertension seems not to be mediated by central Ang II or serum TSH. To summarize, central TRH overproduction in periventricular areas induced by I.C.V. transfection produces hypertension in rats which is reversed by specific antisense treatment. This model may help in testing effective antisense oligodeoxynucleotides against other candidate genes.
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8
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Finkielman S, Firmat J. [A century and a half of the first surgical anesthesia]. Medicina (B Aires) 1996; 56:739-40. [PMID: 9284581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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9
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Garcia SI, Dabsys SM, Martinez VN, Delorenzi A, Santajuliana D, Nahmod VE, Finkielman S, Pirola CJ. Thyrotropin-releasing hormone hyperactivity in the preoptic area of spontaneously hypertensive rats. Hypertension 1995; 26:1105-10. [PMID: 7498977 DOI: 10.1161/01.hyp.26.6.1105] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Thyrotropin-releasing hormone (TRH) plays an important role in central cardiovascular regulation through the activation of different neurotransmitter systems at distinct extrahypothalamic sites. To study possible alterations in the TRH system in the hypertensive state, we measured TRH concentration in cerebrospinal fluid and TRH content of the preoptic area in spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) by radioimmunoassay. In addition, we also measured the density of the TRH receptor in this area by a rapid filtration technique using [3H]methyl-TRH. We found a significant increase in both the TRH content (634 +/- 61 versus 350 +/- 26 pg/mg protein, SHR versus WKY; P < .01, n = 5) and density of TRH receptors without changes in affinity (Bmax, 5.0 +/- 0.1 versus 3.3 +/- 0.1 fmol/mg protein, P < .01, n = 4). An increase in TRH concentration was also found in the cerebrospinal fluid of SHR (30 +/- 3 versus 21 +/- 2 pg/mL, P < .01, n = 5), suggesting increased TRH release in the central nervous system. Northern blot analysis indicated a threefold augmented abundance of TRH precursor mRNA in the preoptic area of SHR. A polyclonal antibody raised against TRH injected peripherally or intracerebroventricularly lowered arterial blood pressure in SHR but not in WKY. In addition, long-term treatment with enalapril (5 mg/kg twice daily), which was effective in inhibiting serum angiotensin-converting enzyme activity by more than 50%, decreased arterial blood pressure and preoptic area TRH content of SHR, whereas another vasodilator, diltiazem (10 mg/kg every 8 hours), failed to produce a similar change.(ABSTRACT TRUNCATED AT 250 WORDS)
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Paez Pereda M, Sauer J, Perez Castro C, Finkielman S, Stalla GK, Holsboer F, Arzt E. Corticotropin-releasing hormone differentially modulates the interleukin-1 system according to the level of monocyte activation by endotoxin. Endocrinology 1995; 136:5504-10. [PMID: 7588301 DOI: 10.1210/endo.136.12.7588301] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The interleukin-1 (IL-1) system is constituted by IL-1 alpha and IL-1 beta and IL-1 receptor antagonist (IL-1ra) that bind the same IL-1 receptors. Hypothalamic-pituitary-adrenal axis hormones are major mediators of the neuroendocrine control over immune function. Corticotropin-releasing hormone (CRH) is produced in peripheral inflammatory sites; its direct effects on inflammatory cytokine synthesis, however, remain unclear. We have studied the effects of CRH (0.1-100 nM) on IL-1 beta and IL-1ra expression by human peripheral monocytes in culture activated with different doses of lipopolysaccharide (LPS). In the absence of LPS, CRH up-regulated IL-1ra and IL-1 beta messenger RNA expression as well as protein synthesis. No significant changes were observed with low doses of LPS (1 ng/ml). In contrast, in combination with high doses of LPS (1 microgram/ml), CRH caused inhibition of IL-1ra and IL-1 beta transcription and secretion. The CRH effects were blocked by its antagonist alpha-helical CRH and mediated by intracellular cAMP. These data indicate that CRH modulates the IL-1 system; depending on the state of activation of the monocyte, CRH exerts an inhibitory control on the activated cell and a stimulatory action on the resting monocyte.
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Rodriguez Vida MI, Kleid MC, Ase A, Finkielman S, Nahmod VE, Vindrola O. Synenkephalin processing in embryonic rat brain. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 1994; 77:151-6. [PMID: 8174224 DOI: 10.1016/0165-3806(94)90191-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Synenkephalin (proenkephalin 1-70) is produced and secreted as an intact molecule or as a part of precursors in the adult brain and adrenal medulla, respectively. However, it is cleaved to low molecular weight peptides in proliferating immune cells. Considering that the pre-proenkephalin gene is expressed in the embryonic rat brain during the cell proliferation stage, we studied the processing of synenkephalin in embryonic rat brains (E18) and compared it with the processing in adult rat brains. IR-synenkephalin was measured by RIA using a C-terminally directed antiserum. Adult rat brains contained higher concentrations of immunoreactive (IR)-synenkephalin (2,612 + 264) than embryonic rat brain (1,361 + 100) (results in fmol/mg proteins, n = 5). Gel filtration chromatography (Sephadex G-50) showed that in the extracts of adult rat brain, 50% of the IR-synenkephalin eluted in the position of the authentic peptide (8 kDa) and the rest of the immunoreactivity corresponded to partially processed peptides of 4.0 and 2.5 kDa. In embryonic rat brains synenkephalin was processed to intermediate peptides of 2.5, 1.7 and mainly to a low molecular weight peptide of 1.0 kDa. The concentration of this last peptide, which was further characterized by affinity column and HPLC, represented 45% of the total immunoreactivity. IR-met-enkephalin in embryonic rat brains (analyzed before and after enzymatic digestion with trypsin and carboxypeptidase B) corresponded principally to non-processed or partially processed products. However, these were cleaved to free met-enkephalin in adult rat brains.(ABSTRACT TRUNCATED AT 250 WORDS)
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Costas MA, Mella D, Criscuolo M, Díaz A, Finkielman S, Nahmod VE, Arzt E. Superinduction of mitogen-stimulated interferon-gamma production and other lymphokines by Sendai virus. JOURNAL OF INTERFERON RESEARCH 1993; 13:407-12. [PMID: 8151134 DOI: 10.1089/jir.1993.13.407] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We observed that Sendai virus preinduction of peripheral blood mononuclear cells and subsequent mitogenic stimulation resulted in: (i) Superproduction of interferon-gamma, (IFN-gamma) (ii) an increase in interleukin-2 (IL-2) synthesis that correlates with DNA synthesis when stimulated with phytohemagglutinin (PHA) or pokeweed mitogen (PWM) after treatment with the Sendai virus, while stimulation with Protein A from Staphylococcus aureus was not affected, and (iii) enhanced tumor necrosis factor-alpha (TNF-alpha) production in response to bacterial lipopolysaccharide (LPS). Treatment of monocyte cultures with LPS and cycloheximide or actinomycin-D inhibited the superinduction phenomenon. When cycloheximide was added at the viral induction time, the inhibition of TNF-alpha superproduction and DNA synthesis was still observed. These results suggest that Sendai virus lymphocyte superinduction is specific for a particular stimulatory pathway, not dependent on mRNA accumulation, and probably mediated by induction of an activating protein.
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Polack E, Nahmod VE, Emeric-Sauval E, Bello M, Costas M, Finkielman S, Arzt E. Low lymphocyte interferon-gamma production and variable proliferative response in anorexia nervosa patients. J Clin Immunol 1993; 13:445-51. [PMID: 8288728 DOI: 10.1007/bf00920020] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Interferon-gamma (IFN-gamma) production by peripheral blood mononuclear cells (PBMC) in 14 patients with anorexia nervosa (AN) was significantly lower than in 14 age-matched healthy controls. Follow-up samples in four patients displayed low levels, except in two when they recovered the IFN-gamma production as the hormonal cycles were restored. A large interindividual variation for the lymphocyte proliferative response was observed in 30 AN patients. DNA synthesis of PBMC was normal in 8 patients (27%), significantly increased in 6 (20%) (P < 0.001), and significantly decreased in 16 (53%) (P < 0.001). IFN-gamma inhibition was reversed by culturing a control lymphocyte population with monocytes from patients with AN. This was not observed in cultures of control monocytes and AN lymphocytes. IL-2 receptor (TAC subunit) was assessed and no difference was found in the number of TAC-positive cells between patients and controls. These results point out impaired production of the immunomodulator cytokine IFN-gamma as a major functional defect of AN peripheral lymphocytes.
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Aloyz R, Vindrola O, Rodríguez Vida MI, Kleid MC, Finkielman S, Nahmod VE. Early complete maturation of proenkephalin processing induced by dexamethasone in the adrenal gland of neonatal rats. Neuroendocrinology 1992; 56:788-96. [PMID: 1369586 DOI: 10.1159/000126309] [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: 11/19/2022]
Abstract
We have previously found that proenkephalin processing is incomplete in the neonatal rat adrenal medulla and have postulated that immaturity of either the nervous input to the gland or the endocrine hypothalamus-pituitary-adrenal axis might be involved in the failure of the gland to yield free met-enkephalin. Therefore, we investigated whether cholinergic and glucocorticoid agonists may act in vivo on neonatal proenkephalin processing; reserpine, a strong activator of precursor cleavage, was also tested. Acute administration of nicotine, pilocarpine and reserpine to 24-hour-old rats increased the content of enkephalin-containing peptides (ECP) after 72 h (4-day-old rats) and activated the posttranslational processing of proenkephalin to high, intermediate and low molecular weight peptides respectively, although free met-enkephalin was not produced. Chronic treatment with nicotine and pilocarpine neither modified the concentration of ECP nor were able to induce free metenkephalin production. Chronic administration of dexamethasone increased ECP levels in the adrenal of 4-day-old rats and caused proenkephalin processing to intermediate- and low-molecular-weight products including the production of free met-enkephalin. These results indicate that only dexamethasone was able to induce the production of met-enkephalin in the adrenal of neonatal rats, suggesting an involvement of the hypothalamus-pituitary-adrenal axis in the proteolytic maturation of proenkephalin during the ontogeny of rat adrenal medulla.
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Garcia SI, Dabsys SM, Santajuliana D, Delorenzi A, Finkielman S, Nahmod VE, Pirola CJ. Interaction between thyrotrophin-releasing hormone and the muscarinic cholinergic system in rat brain. J Endocrinol 1992; 134:215-9. [PMID: 1402531 DOI: 10.1677/joe.0.1340215] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
TRH increases the pressor response to acetylcholine through an increment in muscarinic receptors. As chronic atropinization produces a similar effect, we hypothesized that both phenomena may be related. The effect of chronic atropine treatment on the TRH content of several brain areas in Wistar rats was studied. Atropine produced significant increases in TRH content in the preoptic and septal areas, while decreases were observed in the hypothalamus and hypophysis. The concentration of TRH in cerebrospinal fluid rose significantly in atropine-treated rats compared with controls. A similar effect was observed with eserine, an acetylcholinesterase inhibitor. Finally, perfusion of brain preoptic area slices from normal rats with Krebs-Ringer solution in the presence of pilocarpine increased basal TRH release significantly and this effect was blocked by atropine. These results are compatible with a muscarinic control on the activity of the central TRH system.
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Alvarez AL, Delorenzi A, Santajuliana D, Finkielman S, Nahmod VE, Pirola CJ. Central bradykininergic system in normotensive and hypertensive rats. Clin Sci (Lond) 1992; 82:513-9. [PMID: 1317760 DOI: 10.1042/cs0820513] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
1. The kinin antagonist des-Arg9-[Leu8]bradykinin, injected into the lateral ventricle, caused a long-lasting, dose-dependent reduction in arterial blood pressure and heart rate in spontaneously hypertensive rats but not in normotensive Wistar-Kyoto rats; the antagonist also blocked the pressor response to ventricularly infused bradykinin in both strains. 2. Bradykinin content was increased in the hypothalamus and septum and decreased in the dorsal medulla of spontaneously hypertensive rats when compared with those of normotensive Wistar-Kyoto rats, whereas similar bradykinin contents were observed in the pineal gland, hypophysis and rostroventrolateral medulla of both rat strains. 3. Increased concentrations of bradykinin and its precursor kininogen were found in the cerebrospinal fluid of spontaneously hypertensive rats. 4. Bradykinin receptor numbers, measured as the binding of [125I-Tyr1]bradykinin to nervous tissue, were found to be increased in the dorsal medulla and hypophysis, and to be decreased in the pineal gland, of spontaneously hypertensive rats. 5. Therefore, the central kinin system may participate, by both pre- and post-synaptic mechanisms, in the maintenance of hypertension in spontaneously hypertensive rats.
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Fanelli M, Nahmod VE, Torres N, Santajuliana D, García SI, Finkielman S, Pirola CJ. Brain amines in glucocorticoid-induced hypertension in the rat. Neurosci Lett 1992; 135:189-92. [PMID: 1625793 DOI: 10.1016/0304-3940(92)90433-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A two week administration of the glucocorticoid betametasone to male Wistar rats produced a mild hypertensive state. The brain of these rats showed some significant changes in amine and metabolite content with respect to normotensive controls. Epinephrine and metanephrine were increased in the rostral ventrolateral medulla and in the preoptic area. Epinephrine also increased in the septal area. Normetanephrine decreased in the rostral ventrolateral medulla. Dopamine and homovanillic acid increased in septal and preoptic areas. Dopamine alone increased in rostral ventrolateral medulla. Serotonin and 5-hydroxyindole-3-acetic acid increased in the septal area and dorsal medulla. These changes suggest significant alterations in the aminergic activity of the brain circuitry known to regulate cardiovascular functions; the changes may play a basic role in the development and maintenance of glucocorticoid-induced hypertension.
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Garcia SI, Pirola CJ, Dabsys SM, Santajuliana D, Delorenzi A, Finkielman S, Nahmod VE. The cholinergic system participates in thyrotropin-releasing hormone (TRH) regulation. Neurosci Lett 1992; 135:193-5. [PMID: 1625794 DOI: 10.1016/0304-3940(92)90434-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The effect of chronic atropine treatment was studied on thyrotropin releasing hormone (TRH) content of several brain areas in Wistar rats. Atropine produced TRH increases in the septal area, preoptic area and the hypophysis; this was observed when rats were killed immediately after the last dose, while a decrease was observed only in the hypophysis 48 h after the last atropine dose. TRH concentration in cerebrospinal fluid rose significantly after atropine withdrawal with respect to controls. Treatment with eserine, an acetylcholinesterase inhibitor, produced the same effect. These results indicate cholinergic participation in central TRH regulation.
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Prync AE, Arzt E, Fernandez Castelo S, Finkielman S, Nahmod V. The inhibitory effect of the muscarinic agonist pilocarpine on lymphocyte activation involves the IL-2 pathway and the increase in suppressor cell function. Int J Neurosci 1992; 62:277-85. [PMID: 1305612 DOI: 10.3109/00207459108999780] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The inhibition of lymphocyte DNA synthesis by the cholinergic muscarinic agonist pilocarpine (5 x 10(-4) M) was not reversed by addition of exogenous recombinant Interleukin-2 (100-1000 IU/ml). Pilocarpine did not inhibit Interleukin-2 (IL-2) production by human peripheral blood mononuclear cells but decreased the number of interleukin-2 receptor bearing cells (TAC positive cells). Furthermore, pilocarpine increased the CD8:CD4 T lymphocyte ratio enhancing the suppressor cell function. All these effects were blocked by the muscarinic antagonist atropine (1 x 10(-6) M). As described for the specific lymphocyte nicotinic stimulation, the pure cholinergic muscarinic stimulation inhibits lymphocyte proliferation by enhancing suppressor activity.
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Torres N, Fanelli M, Alvarez AL, Santajuliana D, Finkielman S, Pirola CJ. Glucocorticoid-induced hypertension in rats: role of the central muscarinic cholinergic system. J Endocrinol 1991; 129:269-74. [PMID: 2040860 DOI: 10.1677/joe.0.1290269] [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: 12/29/2022]
Abstract
Betamethasone was administered on alternate days to rats, and the role of the central cholinergic system in the development of hypertension assessed. After 15 days of treatment the systolic blood pressure of treated rats was significantly higher than that of control rats. Peripheral administration of atropine but not of methyl atropine reduced systolic pressure in glucocorticoid-treated rats and had no effect in controls. Therefore, [3H]quinuclidinyl benzylate binding, sodium-dependent high-affinity choline uptake and choline acetyltransferase studies were performed in the septal area, anteroventrolateral medulla (AVLM), anterior hypothalamic preoptic area (AH/PO) and hypothalamus. The density of muscarinic receptors was increased in the hypothalamus and AVLM of treated rats without significant changes in affinity. Choline acetyltransferase activity significantly decreased in the AVLM and increased in the AH/PO. In addition, a decrease in the hypothalamus and an increase in the AH/PO of sodium-dependent high-affinity choline uptake was observed in glucocorticoid-treated rats. These results suggest the presence of an enhanced muscarinic cholinergic activity in several brain nuclei in rats with glucocorticoid-induced hypertension. This activation could be due to pre- and post-synaptic hypersensitivity.
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Labeur M, Nahmod VE, Finkielman S, Arzt E. Lesions of the medial septal nucleus produce a long-lasting inhibition of T lymphocyte proliferation. Neurosci Lett 1991; 125:129-32. [PMID: 1881591 DOI: 10.1016/0304-3940(91)90008-h] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The influence of the central cholinergic system on the immune system was studied in Wistar rats by lesioning the medial septal nucleus. This lesion inhibited T cell proliferation of splenocytes and thymocytes induced by the mitogens concanavalin A (Con A), phytohemagglutinin (PHA) and pokeweed mitogen (PWM) up to 25 days and did not affect proliferation at 40 days after lesioning. In contrast, the response to the B cell mitogen lipopolysaccharide from E. coli (LPS) was not affected at any time. These findings suggest a regulatory role of the cholinergic medial septal nucleus on T lymphocyte proliferation.
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22
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Scheucher A, Alvarez AL, Torres N, Dabsys SM, Finkielman S, Nahmod VE, Pirola CJ. Cholinergic hyperactivity in the lateral septal area of spontaneously hypertensive rats: depressor effect of hemicholinium-3 and pirenzepine. Neuropharmacology 1991; 30:391-7. [PMID: 1712927 DOI: 10.1016/0028-3908(91)90065-j] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In the lateral septal area of spontaneously hypertensive rats, but not in Wistar-Kyoto rats, the selective M1 antagonist, pirenzepine, and the depletion of acetylcholine storage, by hemicholinium-3 (HC-3), decreased blood pressure. The selective M1 agonist McNeil-A-343, produced a pressor response only after treatment of the lateral septal area with HC-3 in spontaneously hypertensive rats. Carbachol, at doses that mainly affect M2 muscarinic receptors, caused no cardiovascular changes in either strain, pointing to the main intervention of the M1 subtype of muscarinic receptor in the hypertensive condition. In addition, increases in the density of binding sites for [3H]QNB and in Vmax of sodium-dependent, HC-3-inhibitable, high affinity uptake of choline were demonstrated, without significant changes of the activity of choline acetyltransferase in the lateral septal area of spontaneously hypertensive rats. These results suggest that a hyperactivity of the cholinergic system of this area could play a role in the development and/or maintenance of hypertension in spontaneously hypertensive rats.
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Bercovich CF, Pirola CJ, Finkielman S, Nahmod VE. Effects of sodium o-iodobenzoate on acid-base parameters and survival in dogs with hemorrhagic shock. CIRCULATORY SHOCK 1991; 33:63-7. [PMID: 2049815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Sodium o-iodobenzoate (OISB) produces an increase in P50 (PO2 at 50% of oxyhemoglobin saturation) and survival when infused at the time of initiation of prolonged hemorrhagic shock in dogs. Acid-base parameters improved during treatment, and plasma lactic acid concentrations showed smaller rises than in nontreated control animals. Erythrocyte 2,3-diphosphoglycerate (2,3-DPG) rose in prolonged hemorrhagic shock in the control group and conversely decreased in OISB-treated dogs. OISB did not require red cell integrity, since its effects were still more marked in hemolyzed blood. The therapeutic benefit of OISB, appears to be related to a direct effect of the agent on the hemoglobin molecule.
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24
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Pirola CJ, Alvarez AL, Finkielman S, Nahmod VE. Release of acetylcholine from isolated canine renal tissue. THE AMERICAN JOURNAL OF PHYSIOLOGY 1991; 260:F198-203. [PMID: 1996671 DOI: 10.1152/ajprenal.1991.260.2.f198] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Slices of canine kidney were incubated with [3H]choline and Ringer-Krebs solution for 30 min. Secretion of [3H]acetylcholine ([3H]ACh) was evoked by either 1) an electrical field stimulation (0.5-1 Hz, 2 ms, 20 V) or 2) high-potassium (57 mM) superfusion for 3 min to depolarize nerve terminals. With these stimulatory schedules, the 3H release mainly consists of [3H]-ACh. The ACh release is Ca2+ dependent and blocked in presence of a Mg2(+)-rich medium. Thus suppression of ongoing neuronal activity by tetrodotoxin and blockade of nicotinic receptors by hexamethonium reduced the electrically evoked ACh release. With both stimulatory procedures, the secretory response was modified by pilocarpine and atropine. In addition, the release of [3H]ACh produced by electrical field stimulation was inhibited by neostigmine, indicating the presence of functional presynaptic receptors in cholinergic putative terminals. Activation of these receptors depresses ACh secretion. The disruption of extrinsic renal nerves 7 days before did not diminish [3H]ACh release caused by K+ stimulation and, conversely, increased [3H]ACh released by electrical field stimulation. These data support the presumed existence of cholinergic nerve terminals in the canine kidney that can release ACh under suitable conditions of stimulation.
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25
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Arzt E, Costas M, Finkielman S, Nahmod VE. Serotonin inhibition of tumor necrosis factor-alpha synthesis by human monocytes. Life Sci 1991; 48:2557-62. [PMID: 2046478 DOI: 10.1016/0024-3205(91)90612-f] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Serotonin inhibited in a concentration dependent way (10(-3) M to 10(-10) M) the LPS induced Tumor Necrosis Factor-alpha synthesis both, when added to the monocyte cultures from the beginning and when added together with the activating stimulus 8 hours before the end of the culture. The inhibitory effect was specifically blocked by the 5-HT1 and 5-HT2 serotonin antagonist methysergide and the 5-HT2 receptor antagonist ketanserin. This indicates that only the 5-HT2 receptor family (5-HT2 or 5-HT1C) may be involved in the inhibitory effect. Serotonin seems to play an important immunomodulatory role in macrophage functions.
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