SABIIA - Sistema Aberto e Integrado de Informação em Agricultura (Sabiia)

Brasil,R.O.; Leal-Cardoso,J.H..

Recent technological developments have created new devices that could improve and simplify the construction of stimulus isolators. HEXFET transistors can switch large currents and hundreds of volts in nanoseconds. The newer opto-isolators can give a pulse rise time of a few nanoseconds, with output compatible with MOSFET devices, in which delays are reduced to nanoseconds. Integrated DC/DC converters are now available. Using these new resources we developed a new electrical stimulus isolator circuit with selectable constant-current and constant-voltage modes, which are precise and easy to construct. The circuit works like a regulated power supply in both modes with output switched to zero or to free mode through an opto-isolator device. The isolator...

Anethole reduces oxidative stress and improves in vitro survival and activation of primordial follicles

Palavras-chave: Electrical isolation; Electrical stimulation; Pulse stimulation; Stimulus isolator.

Ano: 1999

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000600013

Sá,N.A.R.; Bruno,J.B.; Guerreiro,D.D.; Cadenas,J.; Alves,B.G.; Cibin,F.W.S.; Leal-Cardoso,J.H.; Gastal,E.L.; Figueiredo,J.R..

Primordial follicles, the main source of oocytes in the ovary, are essential for the maintenance of fertility throughout the reproductive lifespan. To the best of our knowledge, there are no reports describing the effect of anethole on this important ovarian follicle population. The aim of the study was to investigate the effect of different anethole concentrations on the in vitro culture of caprine preantral follicles enclosed in ovarian tissue. Randomized ovarian fragments were fixed immediately (non-cultured treatment) or distributed into five treatments: α-MEM+ (cultured control), α-MEM+ supplemented with ascorbic acid at 50 μg/mL (AA), and anethole at 30 (AN30), 300 (AN300), or 2000 µg/mL (AN2000), for 1 or 7 days. After 7 days of culture, a...

Antinociceptive effects of the essential oil of Croton nepetaefolius on mice

Palavras-chave: Antioxidant; Anethole; ROS; Primordial follicle; Caprine.

Ano: 2018

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2018000800602

Abdon,A.P.V.; Leal-Cardoso,J.H.; Coelho-de-Souza,A.N.; Morais,S.M.; Santos,C.F..

Croton nepetaefolius Baill., is an aromatic plant native to the northeast of Brazil where it is extensively used in folk medicine as a sedative, orexigen and antispasmodic agent. In the present study the antinociceptive effects of the essential oil of C. nepetaefolius (EOCn), administered orally, were evaluated in male Swiss mice (20-25 g). In the acetic acid-induced writhing test, EOCn (100 and 300 mg/kg; N = 14 and N = 12, respectively) was effective at the highest dose. In the hot-plate test, EOCn at 30 and 300 mg/kg, but not at 3 mg/kg, significantly increased the latency at all observation times up to the 180th min (N = 12 for each dose). In the formalin test, EOCn significantly reduced paw licking in the second phase of the test at 100 mg/kg (N =...

Antinociceptive effects of the essential oil of Croton zehntneri in mice

Palavras-chave: Croton nepetaefolius; Essential oil; Analgesic; Antinociception; Formalin test; Hot-plate test.

Ano: 2002

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2002001000015

Oliveira,A.C.; Leal-Cardoso,J.H.; Santos,C.F.; Morais,S.M.; Coelho-de-Souza,A.N..

Croton zehntneri is an aromatic plant native to Northeastern Brazil, where it is often used in folk medicine. In the present study the antinociceptive effects of the essential oil of Croton zehntneri (EOCz) were evaluated in mice. EOCz administered orally at doses of 100 and 300 mg/kg reduced paw licking time in the second phase of the formalin test from the control value of 41.61 ± 8.62 to 12.01 ± 7.97 and 6.57 ± 3.42 s, respectively. During the first phase of the formalin test only 300 mg/kg induced a significant alteration (from 58.2 ± 7.02, control, to 28.7 ± 4.73 s). The number of contortions in response to intraperitoneal injections of acetic acid did not differ significantly between controls (80.6 ± 9.01) and experimental (300 mg/kg body weight)...

Antinociceptive effects of the essential oil of Mentha x villosa leaf and its major constituent piperitenone oxide in mice

Palavras-chave: Croton zehntneri; Essential oil; Analgesic; Antinociception; Formalin test; Hot-plate test.

Ano: 2001

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001001100016

Sousa,P.J.C.; Linard,C.F.B.M.; Azevedo-Batista,D.; Oliveira,A.C.; Coelho-de-Souza,A.N.; Leal-Cardoso,J.H..

Mentha x villosa Huds (Labiatae) is an aromatic herb widely used in folk medicine. Since the essential oil of the herb has many pharmacological activities, including antispasmodic effects, we determined whether the oil and its major constituent, piperitenone oxide (PO), have antinociceptive activity. The essential oil of M. x villosa (EOMV) and PO administered orally at 200 mg/kg (vehicle: 0.1% Tween 80 in water) significantly reduced the writhings induced by acetic acid from control values of 59.5 ± 3.1 s (N = 10) to 31.9 ± 2.8 s (N = 10) and 23.8 ± 3.4 s (N = 10), respectively. When administered at 100 and 200 mg/kg, EOMV reduced the paw licking time for the second phase of the formalin test from the control value of 20.6 ± 2.1 s (N = 13) to 5.3 ± 2.2 s...

Effects of endurance training on reduction of plasma glucose during high intensity constant and incremental speed tests in Wistar rats

Palavras-chave: Mentha x villosa essential oil; Analgesia; Nociception; Anti-inflammatory effect; Piperitenone oxide.

Ano: 2009

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2009000700010

Abreu,P.; Vitzel,K.F.; Monteiro,I.C.C.R.; Lima,T.I.; Queiroz,A.N.; Leal-Cardoso,J.H.; Hirabara,S.M.; Ceccatto,V.M..

The aim of this research was to investigate the effects of endurance training on reduction of plasma glucose during high intensity constant and incremental speed tests in Wistar rats. We hypothesized that plasma glucose might be decreased in the exercised group during heavy (more intense) exercise. Twenty-four 10-week-old male Wistar rats were randomly assigned to sedentary and exercised groups. The prescription of endurance exercise training intensity was determined as 60% of the maximum intensity reached at the incremental speed test. The animals were trained by running on a motorized treadmill, five days/week for a total period of 67 weeks. Plasma glucose during the constant speed test in the exercised group at 20 m/min was reduced at the 14th, 21st and...

Effects of estragole on the compound action potential of the rat sciatic nerve

Palavras-chave: Exercise; Skeletal muscle; Liver; Blood glucose; Training.

Ano: 2016

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2016001100602

Leal-Cardoso,J.H.; Matos-Brito,B.G.; Lopes-Junior,J.E.G.; Viana-Cardoso,K.V.; Sampaio-Freitas,A.B.; Brasil,R.O.; Coelho-de-Souza,A.N.; Albuquerque,A.A.C..

Estragole, a relatively nontoxic terpenoid ether, is an important constituent of many essential oils with widespread applications in folk medicine and aromatherapy and known to have potent local anesthetic activity. We investigated the effects of estragole on the compound action potential (CAP) of the rat sciatic nerve. The experiments were carried out on sciatic nerves dissected from Wistar rats. Nerves, mounted in a moist chamber, were stimulated at a frequency of 0.2 Hz, with electric pulses of 50-100-µs duration at 10-20 V, and evoked CAP were monitored on an oscilloscope and recorded on a computer. CAP control parameters were: peak-to-peak amplitude (PPA), 9.9 ± 0.55 mV (N = 15), conduction velocity, 92.2 ± 4.36 m/s (N = 15), chronaxy, 45.6 ± 3.74 µs...

Effects of Lippia sidoides essential oil, thymol, p-cymene, myrcene and caryophyllene on rat sciatic nerve excitability

Palavras-chave: Estragole; Essential oil; Sciatic nerve; Compound action potential; Nerve conduction velocity.

Ano: 2004

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2004000800009

Barbosa,R.; Cruz-Mendes,Y.; Silva-Alves,K.S.; Ferreira-da-Silva,F.W.; Ribeiro,N.M.; Morais,L.P.; Leal-Cardoso,J.H..

Lippia sidoides Cham is a typical herb species of Northeast Brazil with widespread use in folk medicine. The major constituents of the essential oil of L. sidoides (EOLs) are thymol, p-cymene, myrcene, and caryophyllene. Several studies have shown that the EOLs and its constituents have pharmacological effects, including antibacterial, anti-inflammatory, antioxidant and neuroprotective activity. Therefore, this work aimed to investigate the effects of the EOLs and their main constituents on rat sciatic nerve excitability. The sciatic nerves of adult Wistar rats were dissected and mounted in a moist chamber. Nerves were stimulated by square wave pulses, with an amplitude of 40 V, duration of 100 μs to 0.2 Hz. Both EOLs and thymol inhibited compound action...

Effects of terpineol on the compound action potential of the rat sciatic nerve

Palavras-chave: Compound action potential; Essential oil; Lippia sidoides; Thyme oil; P-cymene; Myrcene.

Ano: 2017

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2017001200611

Moreira,M.R.; Cruz,G.M.P.; Lopes,M.S.; Albuquerque,A.A.C.; Leal-Cardoso,J.H..

Terpineol, a volatile terpenoid alcohol of low toxicity, is widely used in the perfumery industry. It is an important chemical constituent of the essential oil of many plants with widespread applications in folk medicine and in aromatherapy. The effects of terpineol on the compound action potential (CAP) of rat sciatic nerve were studied. Terpineol induced a dose-dependent blockade of the CAP. At 100 µM, terpineol had no demonstrable effect. At 300 µM terpineol, peak-to-peak amplitude and conduction velocity of CAP were significantly reduced at the end of 180-min exposure of the nerve to the drug, from 3.28 ± 0.22 mV and 33.5 ± 7.05 m/s, respectively, to 1.91 ± 0.51 mV and 26.2 ± 4.55 m/s. At 600 µM, terpineol significantly reduced peak-to-peak amplitude...

Essential oil of Lippia alba and its main constituent citral block the excitability of rat sciatic nerves

Palavras-chave: Essential oil; Alpinia speciosa; Zingiberaceae; Sciatic nerve; Compound action potential; Nerve conduction velocity.

Ano: 2001

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001001000015

Sousa,D.G.; Sousa,S.D.G.; Silva,R.E.R.; Silva-Alves,K.S.; Ferreira-da-Silva,F.W.; Kerntopf,M.R.; Menezes,I.R.A.; Leal-Cardoso,J.H.; Barbosa,R..

Lippia alba is empirically used for infusions, teas, macerates, and hydroalcoholic extracts because of its antispasmodic, analgesic, sedative, and anxiolytic effects. Citral is a mixture of trans-geranial and cis-neral and is the main constituent of L. alba essential oil and possesses analgesic, anxiolytic, anticonvulsant, and sedative effects. The present study evaluated the effects of the essential oil of L. alba (EOLa) and citral on compound action potentials (CAPs) in Wistar rat sciatic nerves. Both drugs inhibited CAP in a concentration-dependent manner. The calculated half-maximal inhibitory concentrations (IC50) of peak-to-peak amplitude were 53.2 µg/mL and 35.00 µg/mL (or 230 µM) for EOLa and citral, respectively. Peak-to-peak amplitude of the CAP...

Essential oil of Pterodon polygalaeflorus Benth attenuates nociception in mice

Palavras-chave: Citral; Nerve excitability; Lippia alba; Sciatic nerve; Essential oil; Compound action potential.

Ano: 2015

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2015000800697

Coelho-de-Souza,A.N.; dos-Santos,C.F.; Lopes-Filho,L.N.; Holanda,F.R.; Oliveira,A.C.; Gomes-Vasconcelos,Y.A.; Oliveira,K.A.; Ferreira-da-Silva,F.W.; Silva-Alves,K.S.; Leal-Cardoso,J.H..

Essential oils (EO) are volatile liquids responsible for the aroma of plants. Pterodon polygalaeflorus seeds have received widespread use in folk medicine for the treatment of inflammatory diseases. For this reason and because Pterodon polygalaeflorus seeds have great EO content, which is frequently pharmacologically active, the present study aimed to evaluate the antinociceptive effect of EO from Pterodon polygalaeflorus (EOPPgfl) and its acute toxic effects. The EEOPPgfl sample, which was extracted by steam distillation of the seeds, had a yield of 2.4% of the seeds weight and had, as major constituents, beta-elemene (48.19%), trans-caryophyllene (19.51%), and epi-bicyclosesquiphellandrene (12.24%). The EOPPgfl sample showed mild acute toxicity and its...

Estragole blocks neuronal excitability by direct inhibition of Na+ channels

Palavras-chave: Essential oil; Pterodon polygalaeflorus; Antinociception; Anti-inflammatory activities; Beta-elemene; Caryophyllene.

Ano: 2018

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2018001100603

Silva-Alves,K.S.; Ferreira-da-Silva,F.W.; Peixoto-Neves,D.; Viana-Cardoso,K.V.; Moreira-Júnior,L.; Oquendo,M.B.; Oliveira-Abreu,K.; Albuquerque,A.A.C.; Coelho-de-Souza,A.N.; Leal-Cardoso,J.H..

Estragole is a volatile terpenoid, which occurs naturally as a constituent of the essential oils of many plants. It has several pharmacological and biological activities. The objective of the present study was to investigate the mechanism of action of estragole on neuronal excitability. Intact and dissociated dorsal root ganglion neurons of rats were used to record action potential and Na+ currents with intracellular and patch-clamp techniques, respectively. Estragole blocked the generation of action potentials in cells with or without inflexions on their descendant (repolarization) phase (Ninf and N0 neurons, respectively) in a concentration-dependent manner. The resting potentials and input resistances of Ninf and N0 cells were not altered by estragole...

Expression of myo-inositol cotransporters in the sciatic nerve and dorsal root ganglia in experimental diabetes

Palavras-chave: Estragole; Local anesthetic; Essential oil; Dorsal root ganglia; Phenylpropanoid; Na+ current.

Ano: 2013

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2013001201056

Farias,V.X.; Uchoa,P.N.; Aquino,C.P.; Britto,L.R.G.; Fonteles,M.C.; Leal-Cardoso,J.H.; Silva-Alves,K.S.; Havt,A.; Prata,M.M.G.; Heimark,D.B.; Nascimento,N.R.F.; Santos,C.F..

The transport of myo-inositol is the main mechanism for the maintenance of its high intracellular levels. We aimed to measure the mRNA and protein levels of myo-inositol cotransporters in the sciatic nerve (SN) and dorsal root ganglia (DRG) during experimental diabetes. Streptozotocin-induced (STZ; 4, 8, and 12 weeks; 65 mg/kg; ip) diabetic rats (DB) and age-matched euglycemic (E) rats were used for the analysis of mRNA and protein levels of sodium myo-inositol cotransporters 1, 2 (SMIT1, SMIT2) or H+/myo-inositol cotransporter (HMIT). There was a significant reduction in the mRNA levels for SMIT1 in the SN and DRG (by 36.9 and 31.0%) in the 4-week DB (DB4) group compared to the E group. SMIT2 was not expressed in SN. The mRNA level for SMIT2 was...

Limb immobilization alters functional electrophysiological parameters of sciatic nerve

Palavras-chave: Diabetic neuropathy; Inositol metabolism; Peripheral nervous tissues.

Ano: 2019

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2019000600609

Alves,J.S.M.; Leal-Cardoso,J.H.; Santos-Júnior,F.F.U.; Carlos,P.S.; Silva,R.C.; Lucci,C.M.; Báo,S.N.; Ceccatto,V.M.; Barbosa,R..

Immobilization, used in clinical practice to treat traumatologic problems, causes changes in muscle, but it is not known whether changes also occur in nerves. We investigated the effects of immobilization on excitability and compound action potential (CAP) and the ultrastructure of the rat sciatic nerve. Fourteen days after immobilization of the right leg of adult male Wistar rats (n=34), animals were killed and the right sciatic nerve was dissected and mounted in a moist chamber. Nerves were stimulated at a baseline frequency of 0.2 Hz and tested for 2 min at 20, 50, and 100 Hz. Immobilization altered nerve excitability. Rheobase and chronaxy changed from 3.13±0.05 V and 52.31±1.95 µs (control group, n=13) to 2.84±0.06 V and 59.71±2.79 µs (immobilized...