RESUMO
AIMS OF THE STUDY: Royal jelly (RJ) is one of the most widely used drugs in traditional medicine. One of its important applications is the repair of skin damage, although the path of its mechanism is still unknown. Platelet-derived growth factor-beta (PDGF-beta) is one of the important factors in wound healing and it has been observed that PDGF-ß expression decreases with increasing age. In this study, for the first time, the effect of RJ on skin wounds has been investigated through the expression of PDGF-ß and tissue studies. MATERIALS AND METHODS: 25 small laboratory male BALB/c mice were selected randomly and after creating a 5 mm wound on the back of their neck, they were treated with doses of 2.5, 10, and 40 mg/kg body weight, After sampling from the healed wound in 9th day, histopathological studies and the expression of PDGF-ß gene were performed by Real-time PCR method. RESULTS: The findings of the present study showed that royal jelly caused a significant increase in PDGF-ß (10.99 times) compared to the healthy group. Also, royal jelly increased the formation of covering tissue or epithelium, the synthesis of collagen, the presence of inflammatory cells, and the formation of new blood vessels. CONCLUSION: The oral treatment of royal jelly is probably effective in skin wound healing by changing the expression of PDGF-ß.
Assuntos
Fator de Crescimento Derivado de Plaquetas , Cicatrização , Camundongos , Masculino , Animais , Fator de Crescimento Derivado de Plaquetas/farmacologia , Fator de Crescimento Derivado de Plaquetas/análise , Fator de Crescimento Derivado de Plaquetas/genética , Colágeno/farmacologia , Ácidos Graxos/farmacologia , Ácidos Graxos/uso terapêuticoRESUMO
Melon seed extracts have high antioxidant activities and are effective against a variety of diseases, including kidney stones. In kidney stone model rats, the anti-urolithiatic effects of the hydro-ethanolic extract of melon seed and potassium citrate were studied and compared. After urolithiasis induction by ethylene glycol, the extract and potassium citrate were treated orally for 38 days concurrent with ethylene glycol. Then, urine and kidney sampling were done, and the urinary parameter levels were measured. The melon and potassium citrate treatments reduced the kidney index, the levels of urinary calcium and oxalate, calcium oxalate deposit numbers, the score of crystal deposits, histo-pathological damages, and the score of inflammation in the kidney sections, while elevating the urinary pH, magnesium, and citrate levels, and also the expression of the UMOD, spp1, and reg1 genes in the kidney of treated animals. The effect of potassium citrate is the same as the effect of melon in treated animals. So, their effects could be by normalizing urinary parameters, reducing crystal deposits, excreting small deposits from the kidney, reducing the chance of them being retained in the urinary tract, and elevating the expression of the UMOD, spp1, and reg1 genes, which are involved in kidney stone formation.
Assuntos
Cucumis melo , Cálculos Renais , Masculino , Animais , Ratos , Citrato de Potássio , Cálculos Renais/tratamento farmacológico , Etilenoglicóis , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , UromodulinaRESUMO
OBJECTIVE: We investigated and compared the effects of taraxasterol, aqueous extract of T. officinale (AET) aerial part, and potassium citrate (PC) on calcium oxalate (CaOx) crystallization in vitro. MATERIALS AND METHODS: CaOx crystallization was induced by adding sodium oxalate to synthetic urine. Taraxasterol (2.5, 5, 7.5 and 12.5 µg/mL), extract (1, 2, 4 and 8 mg/mL), and PC (100, 150, 200 and 350 mg/mL) were subjected to anti-crystallization activities. The absorbance and %inhibition of nucleation of CaOx crystals were evaluated by spectrophotometer at 2, 4, 6, 8, 10, 20, 30, 40, 50 and 60 min and the number and morphology of crystals were studied by light microscopy after 60 min. RESULTS: Presence of taraxasterol, extract and PC decreased absorbance in experimental samples compared to control, significantly. The nucleation of crystals is inhibited by taraxasterol, extract, and PC (26-64, 55-63 and 60-70%, respectively). The number of CaOx crystals were decreased in presence of taraxasterol (p < .01), extract (p < .001), and PC (p < .001) in a dose-dependent manner. Presence of taraxasterol, extract, and PC decreased the number of CaC2O4 monohydrate, while increased CaC2O4 dihydrate crystals, significantly. Also, the diameter of CaC2O4 dihydrate crystals was decreased in presence of taraxasterol, extract and PC, significantly. CONCLUSIONS: This research indicated that taraxasterol and extract have anti-crystallization activities and effectiveness of the extract is more potent than taraxasterol. It could be because of another constituent in the extract with the synergistic effect.
Assuntos
Oxalato de Cálcio/química , Cálculos Renais/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Esteróis/uso terapêutico , Taraxacum/química , Triterpenos/uso terapêutico , Cristalização , Sinergismo Farmacológico , Humanos , Cálculos Renais/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Esteróis/farmacologia , Triterpenos/farmacologia , Urina/química , Água/químicaRESUMO
Taraxasterol is one of the important constituents of Taraxacum officinale L. (Compositae) with antioxidant potential. The present study was designed to evaluate and compare the antiurolithiatic effects of taraxasterol and potassium citrate in the ethylene glycol induced urolithiatic rat. Urolithiasis was induced by ammonium chloride and ethylene glycol in adult male rats. Taraxasterol (2, 4 and 8 mg/kg) and potassium citrate (2.5 g/kg) were treated for 33 days by gavage. Then, the animals were anesthetized and weighted and blood, urine, liver and kidney sampling were done. The kidney sections were prepared by hematoxylin & eosin staining. The liver and kidney coefficients, urine pH, calcium, magnesium, oxalate and citrate levels, serum albumin, calcium and magnesium levels, serum alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase activities, superoxide dismutase and glutathione peroxidase activities in serum, kidney and liver, number of calcium oxalate crystal deposits, score of crystal deposits, score of histopathological damages and score of inflammation in kidney sections were evaluated. The results showed that taraxasterol decreased liver and kidney coefficients (p < 0.001), serum calcium (p < 0.01) level, serum alanine aminotransferase (p < 0.001), aspartate aminotransferase (p < 0.001), lactate dehydrogenase (p < 0.05) activities, urine magnesium (p < 0.05) and oxalate (p < 0.001) levels, number of crystal deposits (p < 0.001), score of crystal deposits (p < 0.01), score of histopathological damages (p < 0.001) and score of inflammation (p < 0.01) in kidney sections, while increased urine pH (p < 0.01), calcium (p < 0.001) and citrate (p < 0.05), serum magnesium (p < 0.001) and albumin (p < 0.01) levels, superoxide dismutase and glutathione peroxidase in serum (p < 0.01), kidney (p < 0.05 and p < 0.001, respectively) and liver (p < 0.01 and p < 0.001, respectively) tissue homogenates in treated urolithiatic rats in comparison to the control urolithiatic rats. The effect of potassium citrate is the same as taraxasterol in treated urolithiatic rats. In conclusion, the effect of taraxasterol could be by improving liver function, changing serum and urine parameters, maintaining the antioxidant environment, reducing crystal deposition, excretion of small deposits from kidney and reducing the chance of them being retained in the urinary tract.
Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Cálculos Renais/tratamento farmacológico , Eliminação Renal/efeitos dos fármacos , Esteróis/farmacologia , Triterpenos/farmacologia , Cloreto de Amônio/toxicidade , Animais , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/uso terapêutico , Etilenoglicol/toxicidade , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Cálculos Renais/induzido quimicamente , Cálculos Renais/urina , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Citrato de Potássio/farmacologia , Citrato de Potássio/uso terapêutico , Ratos , Ratos Wistar , Esteróis/uso terapêutico , Taraxacum/química , Resultado do Tratamento , Triterpenos/uso terapêuticoRESUMO
Many herbal medicines have been recommended for the treatment of dyslipidemia. The antilipidemic effect of hydroethanolic extract of pomegranate peel (Punica granatum L.) was investigated in high lipid diet fed male rats. Intraperitoneally administration of pomegranate peel extract (50, 100, 200, and 300 mg/kg body weight) for 23 days on the levels of serum cholesterol, triglycerides, LDL, HDL, alkaline phosphatase (AP), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) in high lipid diet fed male rats was evaluated. Treatment of pomegranate extract decreased body weight in treated rats, significantly. Administration of the plant extract significantly decreased serum total cholesterol, triglycerides, LDL-C, alkaline phosphatise, AST, and ALT levels, whereas it increased serum HDL-C in high lipid diet fed rats in comparison to saline control group. Also, histopathological study showed that treatment of pomegranate peel extract attenuates liver damage in high lipid diet fed rats in comparison to saline group. It is concluded that the plant should be considered as an excellent candidate for future studies on dyslipidemia.
RESUMO
CONTEXT: Olive [Olea europaea L. (Oleaceae)] is a long-lived evergreen tree that is widespread in different parts of the world. OBJECTIVE: Olive oil has been reported to relieve pain; however, there is still insufficient data in the literature on the subject. Thus, it is considered worthwhile investigating the antinociceptive and anti-inflammatory effects of olive oil in adult male Balb/C mice. MATERIALS AND METHODS: The antinociceptive effects were studied using formalin, hot plate and writhing tests. The acute anti-inflammatory effects of olive oil in mice were studied using xylene ear edema test. Olive oil (1, 5 and 10 ml/kg body wt.) was injected intraperitoneally. Intact animals served as controls. RESULTS: Our results showed that the olive oil only decreased the second phase of formalin-induced pain. In the hot plate test, olive oil did not raise the pain threshold over the 60 min duration of the test. Olive oil exhibited antinociceptive activity against writhing-induced pain by acetic acid. In the xylene ear edema test, olive oil showed significant anti-inflammatory activity in the mice. DISCUSSION AND CONCLUSION: The present data indicated that olive oil has antinociceptive and anti-inflammatory effects in mice but further investigation of these effects is required to elucidate the mechanism(s) involved in analgesic and anti-inflammatory effects of Olea europaea oil.
Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Óleos de Plantas/farmacologia , Analgésicos/administração & dosagem , Animais , Anti-Inflamatórios/administração & dosagem , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Edema/tratamento farmacológico , Edema/fisiopatologia , Inflamação/tratamento farmacológico , Inflamação/fisiopatologia , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Olea/química , Azeite de Oliva , Dor/tratamento farmacológico , Dor/fisiopatologia , Óleos de Plantas/administração & dosagemRESUMO
Molybdenum is an essential trace micronutrient element that plays an important role in animal and plant physiology. Molybdenum is a constituent of at least three mammalian metalloflavoproteins: xanthine oxidase, aldehyde oxidase and sulphite oxidase. In the present study, the hepatoprotective potential of sodium molybdate was investigated against carbon tetrachloride (CCl(4))-induced liver damage in rats. Administration of CCl(4) increased the serum alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase levels in rats and reduced levels of the antioxidant enzymes superoxide dismutase and catalase in the liver. Treatment with sodium molybdate significantly attenuated these changes to nearly undetectable levels. The histopathological changes induced by CCl(4) were also significantly attenuated by sodium molybdate treatment. Therefore, the results of this study suggest that sodium molybdate can protect the liver against CCl(4)-induced oxidative damage in rats, and this hepatoprotective effect might be attributable to its modulation of detoxification enzymes and/or its antioxidant and free radical scavenger effects.
Assuntos
Tetracloreto de Carbono/antagonistas & inibidores , Fígado/efeitos dos fármacos , Molibdênio/farmacologia , Animais , Tetracloreto de Carbono/toxicidade , Masculino , Ratos , Ratos WistarRESUMO
Coriander (Coriandrum sativum L.) is grown as a spice crop all over the world. The seeds have been used to treat indigestion, diabetes, rheumatism and pain in the joints. In the present study, an ethanol extract of the seeds was investigated for effects on insulin release from the pancreatic beta cells in streptozotocin-induced diabetic rats. Blood samples were drawn from the retro-orbital sinus before and 1.5, 3 and 5 h after administration of the seed extract. Serum glucose levels were determined by the glucose oxidase method. To determine the insulin releasing activity, after extract treatment the animals were anaesthetized by diethyl ether, the pancreas was excised, fixed in 10% formaldehyde and embedded in paraffin for sectioning. Pancreatic sections of 5 microm were processed for examination of insulin-releasing activity using an immunocytochemistry kit. The results showed that administration of the ethanol extract (200 and 250 mg/kg, i.p.) exhibited a significant reduction in serum glucose. Administration of streptozotocin decreased the number of beta cells with insulin secretory activity in comparison with intact rats, but treatment with the coriander seed extract (200 mg/kg) increased significantly the activity of the beta cells in comparison with the diabetic control rats. The extract decreased serum glucose in streptozotocin-induced diabetic rats and increased insulin release from the beta cells of the pancreas.
Assuntos
Coriandrum/química , Diabetes Mellitus Experimental/tratamento farmacológico , Células Secretoras de Insulina/efeitos dos fármacos , Insulina/metabolismo , Extratos Vegetais/farmacologia , Animais , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Modelos Animais de Doenças , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Masculino , Ratos , Ratos Wistar , Sementes/químicaRESUMO
OBJECTIVE: The leaves of sage (Salvia officinalis L., Lamiaceae) are reported to have a wide range of biological activities, such as anti-bacterial, fungistatic, virustatic, astringent, eupeptic and anti-hydrotic effects. To determine the mnemogenic effect of sage leaves, we investigated the effects of ethanolic extract of sage leaves and its interaction with cholinergic system on memory retention of passive avoidance learning in rats. METHODS: Post-training intracerebroventricular (i.c.v.) injections were carried out in all the experiments except ethanolic extract (i.p. intraperitoneally). RESULTS: Administration of ethanolic extract (50 mg/kg), pilocarpine (0.5 and 1 mg/rat), the muscarinic cholinoceptor agonist, and nicotine (0.1 and 1 microg/rat) increased, while mecamylamine (1, 5 microg/rat), the muscarinic cholinoceptor antagonist, and mecamylamine (0.01 and 0.1 microg/rat), the nicotine cholinoceptor antagonist decreased memory retention in rats. Activation of muscarinic cholinoceptors by pilocarpine potentiated the response of ethanolic extract. Also, pharmacological blockade of scopolamine attenuated potentiating effect of ethanolic extract. Activation of nicotinic cholinoceptor by nicotine potentiated the response of ethanolic extract. Blockade of nicotinic cholinoceptor by mecamylamine attenuated the response of ethanolic extract. CONCLUSION: It is concluded that the ethanolic extract of salvia officinalis potentiated memory retention and also it has an interaction with muscarinic and nicotinic cholinergic systems that is involved in the memory retention process.
Assuntos
Aprendizagem da Esquiva/efeitos dos fármacos , Memória/efeitos dos fármacos , Extratos Vegetais/farmacologia , Receptores Colinérgicos , Salvia officinalis/química , Andorra , Animais , Aprendizagem da Esquiva/fisiologia , Antagonistas Colinérgicos/metabolismo , Relação Dose-Resposta a Droga , Injeções Intraperitoneais , Masculino , Memória/fisiologia , Agonistas Muscarínicos/metabolismo , Nicotina/agonistas , Nicotina/antagonistas & inibidores , Nicotina/metabolismo , Agonistas Nicotínicos/metabolismo , Pilocarpina/agonistas , Pilocarpina/antagonistas & inibidores , Pilocarpina/metabolismo , Folhas de Planta/química , Ratos , Ratos Wistar , Receptores Colinérgicos/efeitos dos fármacos , Receptores Colinérgicos/metabolismoRESUMO
This study concerned effects of vitamin E and the cholinergic system on memory retention of passive avoidance learning in rats. Post-training intracerebroventricular (i.c.v.) injections were carried out in all experiments. Administrations of vitamin E (10, 25 and 50 microg/rat), nicotine (0.1 microg/rat) and pilocarpine (0.5 microg/rat), the muscarinic receptor agonist increased memory retention, while mecamylamine (0.01, 0.1 and 0.5 microg/rat), the nicotinic receptor antagonist and scopolamine (0.1, 1 and 5 microg/rat), the muscarinic receptor antagonist decreased memory retention. The combination of vitamin E with nicotine or pilocarpine showed potentiation. Effects of mecamylamine or scopolamine were attenuated by vitamin E. It is concluded that vitamin E has a close interaction with cholinergic system in memory retention process.
Assuntos
Memória/efeitos dos fármacos , Sistema Nervoso Parassimpático/efeitos dos fármacos , Vitamina E/uso terapêutico , Vitaminas/uso terapêutico , Animais , Ventrículos Cerebrais/anatomia & histologia , Ventrículos Cerebrais/efeitos dos fármacos , Condicionamento Operante/efeitos dos fármacos , Injeções Intraventriculares , Masculino , Mecamilamina/farmacologia , Agonistas Muscarínicos/uso terapêutico , Antagonistas Muscarínicos/uso terapêutico , Nicotina/farmacologia , Agonistas Nicotínicos/uso terapêutico , Antagonistas Nicotínicos/uso terapêutico , Pilocarpina/farmacologia , Ratos , Ratos Wistar , Receptores Muscarínicos/efeitos dos fármacos , Receptores Nicotínicos/efeitos dos fármacos , Escopolamina/farmacologiaRESUMO
The leaves of sage (Salvia officinalis L., Lamiaceae) are reported to have a wide range of biological activities, such as anti-bacterial, fungistatic, virustatic, astringent, eupeptic and anti-hydrotic effects. To determine the hypoglycaemic effect of sage leaves, we investigated the effects of essential oil and methanolic effect of the plant on healthy and streptozotocin-induced diabetic rats. The animals were made diabetic using by streptozotocin (70 mg/kg, i.p.). The methanolic extract (100, 250, 400 and 500 mg/kg) and essential oil (0.042, 0.125, 0.2 and 0.4 ml/kg) were injected intraperitoneally. The control groups were administered water and sunflower oil as vehicles of methanolic extract and essential oil, respectively. Blood samples were obtained from retro-orbital sinus before administration and 1, 3 and 5 h after administrations. The serum glucose was measured by the enzymatic method of glucose oxidase. The results showed that the essential oil of sage did not change serum glucose, while the plant extract significantly decreased serum glucose in diabetic rats in 3h without effect on insulin releasing from the pancreas but not in healthy rats. Also, the LD(50) of the methanolic extract is measured (4000 mg/kg, i.p.). The present data indicate that sage extract has hypoglycaemic effect on diabetic animals and the plant should be considered in future therapeutic researches.
Assuntos
Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Hipoglicemiantes/farmacologia , Insulina/sangue , Salvia/química , Animais , Hipoglicemiantes/química , Hipoglicemiantes/toxicidade , Injeções Intraperitoneais , Dose Letal Mediana , Masculino , Metanol , Óleos Voláteis/isolamento & purificação , Óleos Voláteis/farmacologia , Óleos Voláteis/toxicidade , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Folhas de Planta/química , Ratos , Ratos Wistar , SolventesRESUMO
The present study investigated the effects of alpha(1)-adrenoceptors and muscarinic cholinoceptors on water intake in adult male rats. Intracerebroventricular (i.c.v.) injections were carried out in all experiments after 24-h deprivation of water. After deprivation, the volume of consumed water was measured for 1 h. Administration of pilocarpine, a muscarinic cholinoceptor agonist (0.5-1 microg/rat), and prazosin, the alpha(1)-adrenoceptors antagonist (2 microg/rat), increased, while scopolamine, a muscarinic cholinoceptor antagonist (5-10 microg/rat), and phenylephrine, an alpha(1)-adrenoceptor agonist (30 microg/rat), decreased water intake in rats. The activation of muscarinic cholinoceptors by pilocarpine attenuated the inhibitory effect induced by phenylephrine. Blockade of muscarinic cholinoceptors did not change the phenylephrine-induced response. Pretreatment with prazosin decreased the pilocarpine-induced response. However, pharmacological blockade of muscarinic cholinoceptors by scopolamine decreased the prazosin-induced effect on water intake. It is concluded that muscarinic cholinoceptors and alpha(1)-adrenoceptors may interact on water intake.
Assuntos
Ingestão de Líquidos/efeitos dos fármacos , Receptores Adrenérgicos alfa 1/fisiologia , Receptores Muscarínicos/fisiologia , Agonistas de Receptores Adrenérgicos alfa 1 , Antagonistas de Receptores Adrenérgicos alfa 1 , Agonistas alfa-Adrenérgicos/administração & dosagem , Agonistas alfa-Adrenérgicos/farmacologia , Antagonistas Adrenérgicos alfa/administração & dosagem , Antagonistas Adrenérgicos alfa/farmacologia , Animais , Ingestão de Líquidos/fisiologia , Injeções Intraventriculares , Masculino , Agonistas Muscarínicos/administração & dosagem , Agonistas Muscarínicos/farmacologia , Antagonistas Muscarínicos/administração & dosagem , Antagonistas Muscarínicos/farmacologia , Fenilefrina/administração & dosagem , Fenilefrina/farmacologia , Pilocarpina/administração & dosagem , Pilocarpina/farmacologia , Prazosina/administração & dosagem , Prazosina/farmacologia , Ratos , Ratos Wistar , Receptores Muscarínicos/efeitos dos fármacos , Escopolamina/administração & dosagem , Escopolamina/farmacologiaRESUMO
The present study investigated the interaction between histamine and opioid systems on water intake in adult male rats. Intracerebroventricular (i.c.v.) injections were carried out in all experiments. Water intake was measured 1 h after drug injections. Administration of histamine (40-80 microg/rat) and naloxone (0.5-1 microg/rat) increased, while morphine (2.5 microg/rat), pyrilamine (25-50 microg/rat), the histamine H1 receptor antagonist, and ranitidine (10-20 microg/rat), the histamine H2 receptor antagonist, decreased water intake in isolated rats. Blockade of histamine H1 and H2 receptors attenuated the histamine-induced response. Pyrilamine, but not ranitidine, increased the inhibitory effect induced by morphine. Also, pharmacological blockade of histamine H1 and H2 receptors decreased the naloxone-induced effect on water intake. It is concluded that the histaminergic system may have a close interaction with morphine and naloxone on drinking behavior.
Assuntos
Analgésicos Opioides/farmacologia , Ingestão de Líquidos/efeitos dos fármacos , Histamina/fisiologia , Morfina/farmacologia , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Animais , Histamina/administração & dosagem , Histamina/farmacologia , Antagonistas dos Receptores Histamínicos H1/farmacologia , Antagonistas dos Receptores H2 da Histamina/farmacologia , Injeções Intraventriculares , Masculino , Ratos , Ratos Wistar , Receptores Histamínicos H1/efeitos dos fármacos , Receptores Histamínicos H2/efeitos dos fármacosRESUMO
In the present study, the effects of the histamine and cholinergic systems on memory retention in adult male rats were investigated. Post-training intracerebroventricular injections were carried out in all the experiments. Cholinoceptor agonist, acetylcholine (1-10 microg/rat) or nicotine (1-10 microg/rat), increased, while a cholinoceptor antagonist, scopolamine (5-20 microg/rat), decreased memory retention. The response to acetylcholine was attenuated by scopolamine. Administration of histamine (5-20 microg/rat) reduced, but the histamine H(1) receptor antagonist, pyrilamine (10-50 microg/rat), and the histamine H(2) receptor antagonist, cimetidine (1-50 microg/rat), increased memory retention in rats. The histamine receptor antagonists attenuated the response to histamine. Histamine reduced the acetylcholine- or nicotine-induced enhancement. The histamine receptor antagonists enhanced the nicotine- or acetylcholine-induced response. Histamine potentiated the inhibitory effect induced by scopolamine. It is concluded that histaminergic and cholinergic systems have opposing effects on memory retention. Also, the histaminergic system elicits an interaction with the cholinergic system in memory retention.
Assuntos
Aprendizagem da Esquiva/fisiologia , Memória/fisiologia , Receptores Colinérgicos/fisiologia , Receptores Histamínicos/fisiologia , Acetilcolina/farmacologia , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Cimetidina/farmacologia , Relação Dose-Resposta a Droga , Antagonistas dos Receptores Histamínicos H1/farmacologia , Antagonistas dos Receptores H2 da Histamina/farmacologia , Masculino , Memória/efeitos dos fármacos , Antagonistas Muscarínicos/farmacologia , Nicotina/farmacologia , Pirilamina/farmacologia , Ratos , Ratos Wistar , Tempo de Reação , Retenção Psicológica/efeitos dos fármacos , Escopolamina/farmacologiaRESUMO
The present study investigated the effect of interactions between histamine receptor agents and the opioid peptidergic system on memory retention of passive avoidance learning in rats. Post-training intracerebroventricular (i.c.v.) injections were carried out in all the experiments. Administration of histamine (20 micro g/rat) reduced, but the histamine H(1) receptor antagonist, pyrilamine (20 and 50 micro g/rat), and the histamine H(2) receptor antagonist, cimetidine (10 and 50 micro g/rat), increased memory retention in rats. The histamine receptor antagonists decreased the response induced by histamine. Morphine (1-10 micro g/rat) reduced, while pentazocine (5 and 10 micro g/rat) or the opioid receptor antagonist, naloxone (5 and 15 micro g/rat), increased memory retention. The combination of histamine with morphine showed potentiation. Effects of pyrilamine and cimetidine were attenuated by morphine. The responses to pentazocine and naloxone also were decreased by histamine. It is concluded that the histaminergic system has an interaction with opioidergic system that is involved in the memory retention process.