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1.
Minerva Gastroenterol Dietol ; 53(4): 311-9, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18043549

RESUMEN

AIM: In several studies, attention is needed to one specific complication, in particularly to hepatocellular carcinoma, which modifies the natural history of liver cirrhosis. Thus, we performed a retrospective cohort analysis to clarify which complications, alone or in combination, are predictive factors of mortality in patients with viral or alcoholic cirrhosis without hepatocellular carcinoma. METHODS: Case records of 255 patients with decompensated viral or alcoholic cirrhosis between January 1990 and December 2000 were retrospectively analyzed. Relevant clinical and laboratory parameters, and their relationship to mortality, were studied. RESULTS: The mean duration of follow-up period was 29 months in which 178 patients (69.8%) died and 77 (31.8%) survived. None of the patients underwent liver transplantation. The cumulative mortality rate of patients with complicated cirrhosis was 38.8% after 1 year, 51.7% after 2 years, 61.1% after 3 years and 65.1% after 8 years. A multivariate Cox's model identified the following variables as significant: age (P=0.001), gastrointestinal bleeding (GB)-ascites combination (P=0.000), encephalopathy-GB-ascites (P=0.028), hepatorenal syndrome (HRS) (P=0.000), GB-spontaneous bacterial peritonitis (SBP) (P=0.001), alkaline phosphatase (ALP) (P=0.004) and the Child-Pugh score (P=0.000). CONCLUSION: The mortality in a group of patients with alcoholic cirrhosis is longer than in those with viral cirrhosis . Moreover, ascites in combination with other complications, HRS and hemorrage-SBP association are independent predictors of mortality in patients with complicated liver cirrhosis.


Asunto(s)
Cirrosis Hepática Alcohólica/mortalidad , Cirrosis Hepática/mortalidad , Cirrosis Hepática/virología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Estudios de Seguimiento , Hepatitis B/complicaciones , Hepatitis B/diagnóstico , Hepatitis C/complicaciones , Hepatitis C/diagnóstico , Humanos , Estimación de Kaplan-Meier , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/etiología , Cirrosis Hepática Alcohólica/complicaciones , Cirrosis Hepática Alcohólica/diagnóstico , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo
2.
Clin Infect Dis ; 37(10): e147-8, 2003 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-14583887

RESUMEN

The protozoan parasite Toxoplasma gondii is an important cause of ocular disease. Ocular toxoplasmosis (OT) can be a progressive and recurring disease that can threaten visual function. We present 2 cases of recurrent OT in immunocompetent patients for whom prophylaxis prevented recurrence of disease.


Asunto(s)
Antiprotozoarios/uso terapéutico , Toxoplasma , Toxoplasmosis Ocular/prevención & control , Adulto , Animales , Quimioprevención , Femenino , Humanos , Inmunocompetencia , Masculino , Prevención Secundaria
3.
Neuropharmacology ; 27(9): 909-14, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2847071

RESUMEN

The results of the present study show that the intracerebroventricular injection of neurokinin A elicited a selective antidipsogenic effect in the rat. Neurokinin A proved to be an extremely potent inhibitor of drinking elicited by subcutaneous administration of hypertonic NaCl, and produced also a statistically-significant inhibition of food-associated drinking. On the other hand, it did not affect drinking evoked by other dipsogenic determinants, such as water deprivation and intracerebroventricular injection of carbachol or of angiotensin II. Thus, neurokinin A shows a spectrum of antidipsogenic activity clearly different from that of substance P, the other mammalian tachykinin so far tested on drinking behaviour in the rat, which appears to be a non-selective antidipsogenic agent. The findings of the present study suggest that different tachykinins, endogenous to the brain of the rat, might subserve distinct roles in the control of drinking behaviour.


Asunto(s)
Ingestión de Líquidos/efectos de los fármacos , Neuroquinina A/farmacología , Angiotensina II/farmacología , Animales , Carbacol/farmacología , Privación de Alimentos , Inyecciones Intraventriculares , Masculino , Neuroquinina A/administración & dosificación , Ratas , Ratas Endogámicas , Cloruro de Sodio/farmacología , Privación de Agua
4.
Br J Pharmacol ; 40(1): 78-85, 1970 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-5487026

RESUMEN

1. Insulin concentration changes in pancreatico-duodenal venous plasma were studied in anaesthetized dogs injected with caerulein.2. Rises in insulin concentration were elicited by rapid intravenous injection of caerulein, as well as by intravenous infusion. Threshold doses were 10 ng/kg and 0.5-1 (ng/kg)/min respectively.3. At the highest dose used (500 ng/kg by rapid intravenous injection and (25 ng/kg)/min by intravenous infusion) the increase in immuno-reactive insulin release was approximately 7 to 9 times the base levels.4. Adrenalectomy potentiated the effects of intravenous infusion of caerulein.5. On a molar basis, caerulein was 2-3 times as active as pancreozymin.6. It is concluded that caerulein is a potent stimulant of pancreatic islets in the dog and that it may be considered as a model peptide, capable of being substituted for pancreozymin in any experiment.7. The mechanism of the insulin stimulating effect of caerulein is discussed. The possibility of a direct "beta-cytotropic" effect of the peptide is suggested.


Asunto(s)
Insulina/metabolismo , Péptidos/farmacología , Glándulas Suprarrenales/fisiología , Adrenalectomía , Animales , Glucemia , Presión Sanguínea , Arterias Carótidas , Colecistoquinina/farmacología , Perros , Inyecciones Intravenosas , Secreción de Insulina , Páncreas/metabolismo , Péptidos/administración & dosificación , Estimulación Química
5.
Br J Pharmacol ; 34(2): 291-310, 1968 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-5687588

RESUMEN

1. In the intact conscious dog, caerulein causes emesis and evacuation of the bowel. The mean effective dose by the intravenous route is 0.4-0.5 mug/kg, and by the subcutaneous route 3-4 mug/kg.2. The gall bladder in situ or as an isolated preparation is highly sensitive to caerulein. A few ng/kg injected intravenously are sufficient to stimulate the gall bladder in situ and less than 1 ng/kg per min is effective when infused intravenously. The isolated gall bladder is contracted by caerulein in concentrations as low as 0.03-2 ng/ml. Krebs solution. There is no tachyphylaxis but, generally, a good dose-response relationship. Hence the gall bladder, especially that of the guinea-pig, appears to be very suitable for the bioassay of caerulein and related peptides.3. In situ, the musculature of the gastrointestinal tract is also highly sensitive to caerulein. Doses as low as 1-5 ng/kg, administered intravenously, have a spasmogenic action on jejunal loops of the dog, and slightly larger doses contract the small intestine of the cat. The stomach and the large intestine seem to be somewhat less sensitive to the polypeptide. Caerulein has a considerable spasmogenic action on the rat pylorus but relaxes the sphincter of Oddi of the guinea-pig.4. Isolated preparations of the gastrointestinal tract are relatively insensitive to caerulein and tachyphylaxis occurs readily.5. Blockade with atropine produces different effects in different intestinal segments and in different animal species. The spasmogenic action of caerulein on the gall bladder is atropine-resistant.6. The effects of caerulein are similar to those of cholecystokinin-pancreozymin in the organs tested in situ or as isolated preparations. Caerulein, however, is always more potent than cholecystokinin-pancreozymin, even on a molar basis. Compared with caerulein, human gastrin I has negligible activity.7. The possible use of caerulein in cholecystography is discussed.


Asunto(s)
Sistema Digestivo/efectos de los fármacos , Vesícula Biliar/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Péptidos/farmacología , Animales , Atropina/farmacología , Bioensayo , Colecistografía , Colecistoquinina/farmacología , Perros , Yeyuno/efectos de los fármacos , Taquifilaxis , Vómitos/inducido químicamente
6.
Br J Pharmacol ; 37(1): 185-97, 1969 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-5824930

RESUMEN

1. Caerulein displayed a potent stimulant action on pancreatic secretion in the dog. Threshold doses were 1-5 ng/kg by rapid intravenous injection, 0.25-1 ng/kg per min by intravenous infusion and 50-100 ng/kg by subcutaneous injection. There was a conspicuous increase not only in the volume flow of pancreatic juice but also in the output of solid constituents of the juice and of amylase. However, continuous stimulation of pancreatic secretion by intravenous infusion of caerulein resulted in a progressive reduction of the amylase concentration and still more of the dry residue content of pancreatic juice. The bicarbonate concentration in pancreatic juice produced by caerulein was similar to that observed in juice secreted following pancreozymin administration or following other stimuli causing the same rate of flow of pancreatic juice.2. On a molar basis, caerulein was 25-30 times as active as human gastrin I and 3-6 times as active as cholecystokinin-pancreozymin. The presence in the molecule of caerulein of a sulphated tyrosyl residue at position 4 of the decapeptide (position 7 starting from the C-terminus) was a necessary prerequisite for the manifestation of the cholecystokinin-pancreozymin-like actions of caerulein. The C-terminal heptapeptide of caerulein retained much of the activity of the intact caerulein molecule.3. At high dose levels (50-200 ng/kg in the dog, 1 mug/kg in the rat, by rapid intravenous injection) caerulein stimulated the flow of hepatic bile in the dog and the rat. The dry residue of the bile and the cholesterol concentration were appreciably greater in rats treated with caerulein than in control rats.4. The activity spectrum of caerulein was identical with that of cholecystokinin-pancreozymin. This is readily explained on the basis of the almost identical structure of the C-terminal octapeptide of the two peptides.5. Caerulein and some caerulein-like peptides may be considered as model peptides, capable of being substituted for cholecystokinin-pancreozymin in all the possible experimental and clinical uses of the duodenal hormone, with the important advantage that they are more easily available.6. The question is raised whether cholecystokinin-pancreozymin obtained from the duodenum by acid extraction is the authentic hormone or rather a carrier polypeptide from which a smaller active peptide may be set free, when needed, into the circulation.


Asunto(s)
Bilis/metabolismo , Páncreas/efectos de los fármacos , Péptidos/farmacología , Amilasas/análisis , Animales , Bicarbonatos/análisis , Bilis/análisis , Colecistoquinina/farmacología , Perros , Femenino , Inyecciones Intravenosas , Inyecciones Subcutáneas , Hígado/efectos de los fármacos , Masculino , Páncreas/metabolismo , Jugo Pancreático/análisis , Péptidos/administración & dosificación , Ratas
7.
Br J Pharmacol ; 37(1): 198-206, 1969 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-5824931

RESUMEN

1. The South American amphibian Phyllomedusa sauvagei contains in its skin large amounts of a polypeptide closely resembling caerulein in its pharmacological actions. This polypeptide, called phyllocaerulein, was obtained in a pure form, and upon acid hydrolysis, enzymic digestion and end-group determination experiments it proved to be a nonapeptide of the following composition Pyr-Glu-Tyr(SO(3)H)-Thr-Gly-Trp-Met-Asp-Phe-NH(2)It may be seen that caerulein and phyllocaerulein have in common the C-terminal heptapeptide and the N-terminal pyroglutamyl residue.2. Phyllocaerulein is indistinguishable from caerulein even in parallel bioassay. However, the former polypeptide seems to be somewhat more potent than the latter on all the preparations tested.3. In different batches of Phyllomedusa sauvagei skin the phyllocaerulein content ranged between 150 and 600 mug/g of fresh tissue.Phyllocaerulein or similar polypeptides occur also in the skin of several other Phyllomedusa species, among which are Phyll. burmeisteri, Phyll. dachnicolor, Phyll, helenae, Phyll. annae, Phyll. callidryas and Phyll. bicolor.4. The qualitative identification and quantitative estimation of caerulein-like polypeptides in crude skin extracts may be complicated by the concomitant occurrence of other active polypeptides. These, however, are poorly effective on some test preparations which seem to respond selectively to caerulein.5. Like that of caerulein, the biological significance of phyllocaerulein is completely obscure.


Asunto(s)
Anfibios , Péptidos/análisis , Péptidos/farmacología , Secuencia de Aminoácidos , Animales , Bioensayo , Presión Sanguínea/efectos de los fármacos , Cromatografía en Papel , Vesícula Biliar/efectos de los fármacos , Jugo Gástrico/metabolismo , Íleon/efectos de los fármacos , Jugo Pancreático/metabolismo , Piel/análisis
8.
Br J Pharmacol ; 38(1): 221-8, 1970 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-5413288

RESUMEN

1. The South American amphibian Leptodactylus pentadactylus labyrinthicus and the South African amphibian Xenopus laevis contain in their skin a polypeptide indistinguishable from caerulein prepared from the Australian amphibian Hyla caerulea.2. The caerulein content of different batches of Leptodactylus pentadactylus labyrinthicus skins varies from 10 to 500-600 mug/g tissue. Drying of the skin causes either a moderate decrease or a slight increase in the caerulein content. Methanol extraction gives considerably higher yields of caerulein than acetone extraction.3. Caerulein or caerulein-like polypeptides also occur in the skin of several other species of Leptodactylus together with 5-hydroxyindole alkylamines and imidazole alkylamines. Yet other species of Leptodactylus lack caerulein-like polypeptides and 5-hydroxyindole alkylamines.4. It is suggested that caerulein and caerulein-like polypeptides may have some function either in the regulation of secretory processes of the skin or in the exchange of water and electrolytes through the skin, or in both.


Asunto(s)
Anuros , Péptidos/análisis , Piel/análisis , Aminas/análisis , Animales , Bioensayo , Cromatografía , Cromatografía en Papel , Perros , Cobayas , Imidazoles/análisis , Indoles/análisis , Péptidos/aislamiento & purificación , Péptidos/fisiología , Extractos de Tejidos
9.
Aliment Pharmacol Ther ; 17(12): 1563-9, 2003 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-12823161

RESUMEN

BACKGROUND: Trans-catheter arterial chemoembolisation (TACE) is the most common palliative treatment for hepatocellular carcinoma (HCC). The therapeutic options depend both on the characteristics of the tumour and on functional staging of the cirrhosis. AIM: To evaluate the effects of TACE on the survival of cirrhotic patients with HCC according to different staging systems [Okuda score, Cancer Liver Italian Program (CLIP) score, Model for End-stage Liver Disease (MELD) score] and in relation to the side-effects of TACE. METHODS: Fifty cirrhotic patients, 36 CTP class A and 14 class B, underwent 106 TACE treatments with mitoxantrone. Survival at 12, 24, and 36 months was evaluated. RESULTS: MELD at 12 months and CLIP at 24 months were identified as significant variables associated with survival. Combined cut-offs of CLIP and of MELD identified four subgroups of patients with different survivals, at 12, 24 and 36 months, respectively: CLIP >or= 2 and MELD >or= 10 (63%, 20% and 0%), CLIP < 2 and MELD >or= 10 (73%, 40% and 22%), CLIP >or= 2 and MELD < 10 (73%, 40% and 22%) and CLIP < 2 and MELD < 10 (100%, 63% and 50%). Post-TACE side-effects proved to have no influence on survival. CONCLUSION: In patients with poor probability of survival (CLIP >or= 2 and MELD >or= 10), TACE must be planned with a great deal of caution, while in patients with possibly good outcomes (CLIP < 2 and MELD < 10), more 'aggressive' therapy should be taken into consideration.


Asunto(s)
Carcinoma Hepatocelular/tratamiento farmacológico , Quimioembolización Terapéutica/métodos , Cirrosis Hepática/virología , Neoplasias Hepáticas/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Fallo Hepático/etiología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Cuidados Paliativos , Análisis de Supervivencia , Resultado del Tratamiento
10.
Brain Res Mol Brain Res ; 47(1-2): 78-86, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9221904

RESUMEN

It is well-known that central administration of tachykinins (Tks) inhibit salt intake in rats. Recent studies have shown that conditions that arouse salt appetite, such as adrenalectomy and sodium depletion, induce a decrease in preprotachykinin-A (PPT-A) mRNA in discrete regions of the rat brain, suggesting that reduced levels of PPT-A mRNA in the brain may have a permissive role on the expression of salt appetite. It has also been shown that spontaneously hypertensive rats (SHR) show higher avidity for salty solutions than their normotensive control Wistar-Kyoto (WKY) rats. In this regard, the present study tested whether SHR and WKY rats differ in expression of the gene coding for PPT-A, the precursor for Tks peptides. Using semi-quantitative in situ hybridization histochemistry, we examined the level of PPT-A mRNA in discrete rat brain regions of SHR and WKY rats under no treatment, after 1 or 3 days of Na+ depletion. Levels of PPT-A mRNA were analysed in the olfactory tubercle (Tu), in the lateral olfactory tubercle (LOT), in the dorsal and ventral caudate putamen (d/v CPu), in the medial preoptic area (mPOA), in the bed nucleus of the stria terminalis (BNST), in the habenula (Hb) and in the postero-dorsal part of the amygdala (MePD). Semi-quantitative analysis of silver grains revealed a 27.5% lower expression of the PPT-A mRNA levels in SHR opposite to WKY rats under no treatment in v-CPu, mPOA, BNST and Hb. 1 day of Na+ depletion reduced PPT-A mRNA levels when opposite to Na+-repleted animals in Tu and mPOA in both SHR and WKY rats. On the other hand, when comparing SHR and WKY rats after 1 day of Na+ depletion, a 26% lower level of PPT-A mRNA was detected in Tu and d-CPu of SHR opposite to WKY rats whereas a 14% and an 18% lower level was detected in v-CPu and Hb, respectively. A lower expression of PPT-A mRNA in SHR compared to WKY rats was also found in BNST and MePD, although no statistical significance was detected in these two brain areas. In the last experiment, 3 days of Na+ depletion reduced PPT-A mRNA levels in mPOA while negligibly increased mRNA levels in d-CPu and v-CPu, in BNST, Hb and MePD, both in SHR and WKY rats. Conversely, when making comparisons between the two strains, a 35% lower level of PPT-A mRNA in SHR with respect to WKY rats was found after 3 days of Na+ depletion in d-CPu, v-CPu and mPOA. A lower gene expression, even though not statistically significant, was found in Tu, LOT, MePD. These findings show a consistent difference of PPT-A mRNA levels in discrete regions of the SHR brain opposite to WKY rats and confirm that 1 day of Na+ depletion reduces PPT-A mRNA in discrete brain regions. Since SHR are notoriously more salt-avid than WKY rats and Tks are potent inhibitors of sodium intake, the down-regulation of PPT-A mRNA may contribute to the higher natriophilia and, therefore, to the etiology of the hypertensive disease.


Asunto(s)
Encéfalo/metabolismo , Hipertensión/metabolismo , Precursores de Proteínas/metabolismo , Taquicininas/metabolismo , Animales , Modelos Animales de Enfermedad , Hipertensión/genética , Masculino , ARN Mensajero/metabolismo , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY
11.
Psychopharmacology (Berl) ; 68(3): 243-7, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-6156471

RESUMEN

Intracerebroventricular injections of the naturally occurring tachykinins eledoisin, physalaemin and substance P elicit a powerful antidipsogenic effect in the rat, while in the pigeon they potently stimulate water intake. The aim of this paper was to study in conscious rats and pigeons the vascular effect of these peptides and to compare this effect to the one elicited on water intake. The results of these experiments demonstrate that there is no direct relationship between the two effects. Our findings suggest that the effect of these peptides on water intake might be specific on CNS and not related to their vascular activity.


Asunto(s)
Autacoides/farmacología , Presión Sanguínea/efectos de los fármacos , Conducta de Ingestión de Líquido/efectos de los fármacos , Animales , Columbidae , Eledoisina/farmacología , Femenino , Hemodinámica , Inyecciones Intravenosas , Inyecciones Intraventriculares , Masculino , Fisalemina/farmacología , Ratas , Sustancia P/farmacología
12.
Peptides ; 6 Suppl 3: 181-5, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-2421260

RESUMEN

Nonmammalian peptides of the tachykinin, bombesin and opioid families, injected into the brain ventricles, potently and specifically affect drinking behaviour of rats and pigeons. These peptides, or at least their counterparts, have been found in the brain of mammals and birds. It has been hypothesized that these endogenous brain peptides belong to a "brain peptidergic system" which participates in the control of water intake and body fluid homeostasis.


Asunto(s)
Bombesina/farmacología , Conducta de Ingestión de Líquido/efectos de los fármacos , Endorfinas/farmacología , Proteínas del Tejido Nervioso/farmacología , Angiotensina II/farmacología , Animales , Columbidae , Eledoisina/farmacología , Encefalinas/farmacología , Oligopéptidos/farmacología , Péptidos Opioides , Fisalemina/farmacología , Ácido Pirrolidona Carboxílico/análogos & derivados , Ratas , Sustancia P/farmacología , Taquicininas , Vasopresinas/sangre , Equilibrio Hidroelectrolítico/efectos de los fármacos
13.
Peptides ; 21(7): 1051-62, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10998540

RESUMEN

Nociceptin/orphanin FQ (NC), the endogenous ligand of the opioid receptor-like1 (ORL1) receptor, has been reported to stimulate feeding in rats. The present article reviews the studies so far published on the effect of NC on food intake and reports new findings concerning the sensitivity of brain regions to the hyperphagic effect of NC in rats. The results obtained indicate that the hypothalamic arcuate nucleus is the most sensitive site among the brain regions so far investigated. On the basis of these findings and of the neurochemical and electrophysiological effects of NC, possible mechanisms of action and possible interactions with other neurotransmitter systems affecting feeding are discussed.


Asunto(s)
Péptidos Opioides/farmacología , Péptidos Opioides/fisiología , Vasodilatadores/farmacología , Analgésicos Opioides/metabolismo , Animales , Encéfalo/efectos de los fármacos , Ritmo Circadiano/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Conducta Alimentaria/efectos de los fármacos , Hipotálamo/efectos de los fármacos , Ligandos , Masculino , Antagonistas de Narcóticos , Narcóticos/metabolismo , Neuropéptido Y/metabolismo , Oligonucleótidos Antisentido/metabolismo , Péptidos Opioides/metabolismo , Proopiomelanocortina/metabolismo , Ratas , Ratas Wistar , Receptores Opioides/agonistas , Receptores Opioides/metabolismo , Serotonina/metabolismo , Factores de Tiempo , Ácido gamma-Aminobutírico/metabolismo , Receptor de Nociceptina , Nociceptina
14.
Peptides ; 21(11): 1597-609, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11090913

RESUMEN

The present article reviews the studies so far published on the psychopharmacological effects mediated by tachykinin NK-3 receptors in laboratory animals. Central administration of NK-3 receptor agonists has been reported to attenuate alcohol intake in alcohol-preferring rats and to evoke conditioned place preference. These findings suggest that NK-3 receptors may affect reward processes to drugs of abuse. Anxiolytic-like and antidepressant-like effects have been previously reported for NK-1 receptor antagonists, and anxiolytic-like effects for NK-2 receptor antagonists. More recently, it has been shown that NK-3 receptor agonists have anxiolytic-like and antidepressant-like effects in mice and rats, while an NK-3 receptor antagonist was reported to be anxiogenic in mice. These findings indicate that different TK receptor subtypes may be involved in anxiolytic-like and antidepressant-like effects in laboratory animals and raise interest for the possible role of NK-3 receptors in the control of anxiety and depression in man.


Asunto(s)
Receptores de Neuroquinina-3/fisiología , Consumo de Bebidas Alcohólicas , Animales , Ansiolíticos/farmacología , Antidepresivos/farmacología , Encéfalo/metabolismo , Hipoxia , Ratones , Neurotransmisores/metabolismo , Ratas , Receptores de Neuroquinina-3/agonistas , Receptores de Neuroquinina-3/antagonistas & inhibidores
15.
Peptides ; 9(2): 347-56, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-2453857

RESUMEN

The present study investigated the sensitivity of 12 forebrain and midbrain structures to the antidipsogenic effect of eledoisin, physalaemin and substance P on angiotensin-induced drinking. The three tachykinins elicited the most potent effects when injected into the nucleus preopticus medialis, the nucleus anterior hypothalami and the subfornical organ. In other sites (nuclei lateralis, ventromedialis and posterior hypothalami, nucleus septi lateralis, nucleus interpeduncularis and substantia grisea periventricularis) the effect was lower, and most of these sites showed different sensitivity to the three tachykinins. Finally, the nucleus septi medialis, the nucleus preopticus lateralis and the substantia nigra were refractory to the three tachykinins. These results show that: (1) the antidipsogenic effect of tachykinins can be elicited not only in forebrain, but also in midbrain structures such as the substantia grisea periventricularis and the nucleus interpeduncularis; (2) the distribution of brain sites sensitive to the antidipsogenic effect of substance P and physalaemin is always overlapping, while this is not true for eledoisin. This probably reflects selective distribution and/or activation of distinct subtypes of tachykinin receptors.


Asunto(s)
Encéfalo/fisiología , Conducta de Ingestión de Líquido/efectos de los fármacos , Neuropéptidos/farmacología , Angiotensina II/farmacología , Animales , Encéfalo/anatomía & histología , Encéfalo/efectos de los fármacos , Eledoisina/farmacología , Masculino , Especificidad de Órganos , Fisalemina/farmacología , Ratas , Ratas Endogámicas , Valores de Referencia , Sustancia P/farmacología , Taquicininas
16.
Peptides ; 5(3): 607-13, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6473174

RESUMEN

The effects on ingestive behavior of the naturally occurring bombesin-like peptides ranatensin and litorin were studied in comparison to those of bombesin by intracerebroventricular pulse injection or by continuous infusion in the rat. Ranatensin and litorin, like bombesin, proved to inhibit drinking and feeding behavior. Marked differences, however, were observed in their effects. In particular our results indicate that these peptides possess different selectivity of action on drinking elicited by different dipsogenic stimuli and different potency and effectiveness in inhibiting food intake induced by food deprivation. Moreover, the effects of the three peptides were markedly affected also by the modality of administration (pulse injection or continuous infusion). On the basis of these results it seems possible to hypothesize that the endogenous bombesin-like peptides may differently affect rat ingestive behavior according to their structure and to the rate and modality of their release in the brain.


Asunto(s)
Bombesina/farmacología , Conducta de Ingestión de Líquido/efectos de los fármacos , Conducta Alimentaria/efectos de los fármacos , Oligopéptidos/farmacología , Péptidos/farmacología , Vasoconstrictores/farmacología , Animales , Bombesina/administración & dosificación , Privación de Alimentos , Inyecciones Intraventriculares , Cinética , Masculino , Oligopéptidos/administración & dosificación , Ácido Pirrolidona Carboxílico/análogos & derivados , Ratas , Ratas Endogámicas , Factores de Tiempo
17.
Peptides ; 19(8): 1399-406, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9809655

RESUMEN

Bombesin (BN) injected to sodium depleted rats either centrally, particularly into the paraventricular nucleus (PVN) or peripherally by intraperitoneal (IP) route, exerts a potent inhibitory effect on the intake of 2% sodium chloride. To determine whether the area postrema (AP) and the lateral parabrachial nucleus (LPBN), which are known to be involved in the control of ingestive behavior, could be sites for the antinatiorexic activity of BN, we studied the effects of injections of this peptide into the LPBN or, by IP or fourth ventricular route, to surgically AP-lesioned rats. We observed that in sodium depleted rats: 1) injected into the LPBN at a dose of 50, but not of 25, ng per nucleus, BN significantly reduced the intake of 2% sodium chloride; 2) administered either intraperitoneally or into the fourth brain ventricle, BN induced a potent antinatriorexic effect in AP-sham lesioned animals; and 3) in the same experimental conditions, surgical ablation of the AP did not reduce the antinatriorexic effect of the peptide. These data indicate that the LPBN may be, with the PVN, a site for the BN-ergic inhibitory control of salt appetite and that the AP, which has been implicated in BN-induced anorexia, does not play a role in the antinatriorexic effect of this peptide.


Asunto(s)
Bombesina/farmacología , Conducta de Ingestión de Líquido/efectos de los fármacos , Natriuresis/efectos de los fármacos , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , Cloruro de Sodio Dietético/antagonistas & inhibidores , Animales , Dieta Hiposódica , Inyecciones Intraventriculares , Masculino , Ratas , Ratas Wistar , Cloruro de Sodio Dietético/metabolismo
18.
Peptides ; 11(2): 339-44, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2162534

RESUMEN

Neurokinin A (NKA), which selectively inhibits only cellular dehydration (CD)-induced drinking in adult rats, exerts a more general antidipsogenic effect in pups in which it also inhibits drinking induced by angiotensin II (AII) or suckling deprivation (SD). The inhibition of drinking is precocious (1st-3rd day) and never involves the intake of milk. The inhibition of CD-induced drinking increases with age, while that of AII- or SD-induced drinking progressively decreases and disappears on day 12-15. In the rat, NKA is therefore a precocious and selective inhibitor of drinking behavior and its selectivity is achieved ontogenetically.


Asunto(s)
Encéfalo/fisiología , Ingestión de Líquidos/fisiología , Neuroquinina A/fisiología , Agua/metabolismo , Envejecimiento/fisiología , Análisis de Varianza , Angiotensina II/farmacología , Animales , Animales Lactantes/metabolismo , Femenino , Privación de Alimentos , Inyecciones Intraventriculares , Masculino , Leche , Neuroquinina A/administración & dosificación , Neuroquinina A/farmacología , Ratas , Ratas Endogámicas , Respuesta de Saciedad/efectos de los fármacos , Respuesta de Saciedad/fisiología
19.
Peptides ; 19(1): 149-55, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9437747

RESUMEN

The order of potency of tachykinin (TK) receptor agonists suggests that TK NK-1 receptors mediate their inhibitory effect on water intake induced by intracerebroventricular (i.c.v.) injection of angiotensin II (AngII) in rats. The present study was aimed at further evaluating which TK receptor subtype mediates the effect, using selective antagonists for the TK receptor subtypes. Pulse i.c.v. injection of the TK agonist neuropeptide gamma (NP gamma), 31-250 ng/rat, markedly inhibited AngII-induced water intake. The i.c.v. injection of the NK-1 receptor antagonist SR14033, 0.5 microgram/rat, significantly reduced, while 1 microgram/rat completely abolished the inhibitory effect of NP gamma, 125 ng/rat. The selective NK-2 receptor antagonist SR48968 and the selective NK-3 receptor antagonist R820 were devoid of any effect up to the i.c.v. dose of 2 micrograms/rat. On the other hand, i.c.v. injection of SR140333, 1 microgram/rat, did not increase drinking induced by i.c.v. injection of AngII, 0.1-10 ng/rat, and did not increase drinking in water sated or water deprived rats. The results of the present study confirm that central TKergic mechanisms inhibit AngII-induced drinking in rats, and provide further evidence that TK NK-1 receptors mediate the effect. Failure of i.c.v. injected SR 140333 to increase AngII-induced drinking, as well as water intake in sated or deprived rats suggests that brain NK-1 receptor mechanisms apparently do not exert a tonic control on AngII-induced drinking and, in general, on water intake in rats. From a pharmacological point of view, the inhibitory effect of TKs on the dipsogenic action of AngII can represent a functional test for activity at central NK-1 receptors in rats.


Asunto(s)
Angiotensina II/farmacología , Ingestión de Líquidos/efectos de los fármacos , Receptores de Neuroquinina-1/metabolismo , Angiotensina II/antagonistas & inhibidores , Animales , Benzamidas/farmacología , Encéfalo/efectos de los fármacos , Cateterismo , Indoles/farmacología , Inyecciones , Masculino , Antagonistas del Receptor de Neuroquinina-1 , Neuropéptidos/farmacología , Oligopéptidos/farmacología , Fragmentos de Péptidos/farmacología , Piperidinas/farmacología , Quinuclidinas/farmacología , Ratas , Ratas Wistar , Receptores de Taquicininas/agonistas , Receptores de Taquicininas/antagonistas & inhibidores , Receptores de Taquicininas/clasificación , Taquicininas/farmacología
20.
Peptides ; 16(3): 533-7, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7544465

RESUMEN

The present study evaluated the effect of SC injections of the selective NK3 tachykinin agonist, Suc-[Asp6,MePhe8]substance P(6-11), also referred to as senktide (SENK), on 8% alcohol intake in genetically selected alcohol-preferring rats. Animals were offered access to 8% ethanol for 2 h/day (between 1800 and 2000 h) and to tap water for 4 h/day (between 1800 and 2200 h); SENK was injected 10 min before access to fluids. The peptide significantly reduced alcohol intake at doses of 125 and 250 micrograms/kg, but not at 62.5 micrograms/kg. The reduction in alcohol intake was accompanied by a sharp increase in water intake, so that total fluid intake was never significantly modified. The same SC doses of SENK did not modify water intake in rats with access to water, as the only fluid, for 4 h/day. In food-deprived rats food intake was not altered by 125 micrograms/kg, whereas 250 micrograms/kg produced a reduction in food intake that was smaller in intensity and shorter lasting than the reduction in alcohol intake. The same doses of SENK did not modify 0.1% saccharin intake, nor did they elicit major competing behaviors. The results of the present study are in keeping with those obtained following central injection of NK3 agonists, and show that a behaviorally selective reduction of alcohol intake can be evoked also by peripheral administration of SENK.


Asunto(s)
Consumo de Bebidas Alcohólicas/tratamiento farmacológico , Conducta de Elección/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Sustancia P/análogos & derivados , Análisis de Varianza , Animales , Conducta de Ingestión de Líquido/efectos de los fármacos , Conducta Alimentaria/efectos de los fármacos , Inyecciones Subcutáneas , Masculino , Actividad Motora/efectos de los fármacos , Ratas , Ratas Endogámicas , Sacarina/farmacología , Sustancia P/farmacología
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