63 research outputs found
Development of smooth muscle electromyographic method: detection and interpretation of slow wave activities in gastrointestinal tract and pregnant uterus
The combined uterorelaxant effect of sildenafil and terbutalin in the rat: The potential benefit of co-administration of low doses
Non-genomic uterorelaxant actions of corticosteroid hormones in rats: An in vitro and in vivo study
Identification of myoelectric signals of pregnant rat uterus: new method to detect myometrial contraction
Aim To develop an electromyography method for pregnant
rat uterus in vivo and to separate myometrial signals
from the gastrointestinal tract signals.
Methods: Pregnant Sprague-Dawley rats (n = 8) were anaesthetized
and their stomach, small intestine, and large intestine
were removed from the abdomen. A pair of thread
electrodes was inserted into the uterus, while a pair of disk
electrodes was placed subcutaneously above the myometrium.
Additionally, a strain gauge sensor was fixed on the
surface of the myometrium and cecum for the parallel detection
of mechanical contractions in rats (n = 18) with intact
gastrointestinal tract. The filtered electric signals were
amplified and recorded by an online computer system and
analyzed by fast Fourier transformation. The frequency of
the electric activity was characterized by cycle per minute
(cpm), the magnitude of the activity was described as
power spectrum density maximum (PsDmax).
Results: The frequency of the pregnant uterine activity
was 1-3 cpm, which falls within the same range as that of
cecum. Measuring by both electrodes, oxytocin (1 μg/kg)
increased and terbutaline (50 μg/kg) decreased the PsDmax
by 25%-50% (P < 0.001) and 25%-40% (P < 0.01), respectively.
We found a strong positive correlation between the
alterations of PsDmax values and the strain gauge sensordetected
mechanical contractions (area under curve). The
GI specific compounds (neostigmine, atropine) mainly affected
the cecal activity, while myometrium specific drugs
(oxytocin, terbutaline) influenced the myometrial signals
only.
Conclusion: Our method proved to be able to detect the
myoelectric activity that reflects the mechanical contraction.
The overlapping myometrial and cecal signals are not
separable, but they can be distinguished based on the
much higher activity and different pharmacological reactivity
of the pregnant uterus. Thus, the early signs of contractions
can be detected and labor may be predicted in a
fast and sensitive way
Increase in Alzheimer's related markers preceeds memory disturbances: Studies in vasopressin-deficient Brattleboro rat
Alzheimer's disease (AD) is the most common form of dementia in the elderly. For more effective therapy early diagnostic markers could be beneficial. Therefore we compared one year old rats with adults and examined if changes in possible brain markers of AD preceeded memory decline. We also tested if vasopressin-deficient animals were useful model of AD as vasopressin has well known positive effect on memory and AD patient has decreased vasopressin production.
We compared adult (3 month) and old (12 month), normal and vasopressin-deficient Brattleboro rats. To receive a comprehensive picture about their memory we examined their social discrimination, object discrimination and conditioned learning abilities (shuttle box). Amyloid precursor protein (APP), mitogen-activated protein kinase 1 (MAPK1), β-actin and tryptophan 2,3-dioxygenase 2 (TDO2) mRNA levels was measured by quantitative PCR.
There was no difference between the memory of adult and aged groups. The vasopressin-deficient rats at both ages showed a weaker performance in the course of social and object discrimination tests and a higher escape failure during the shuttle box experiment. The brain marker mRNAs of the elder animals were higher than the levels of the adults, but the absence of vasopressin had no influence on them.
Thus, the one year old rats showed elevated levels of AD-related markers, but memory deficits were observable only in vasopressin deficient animals. Vasopressin does not seem to have pathogenic role in AD. Changes in the studied markers might predict later symptoms, although further studies are required for confirmation
A pulykahízlalás jövedelemtermelő képességének alakulása jó színvonalon gazdálkodó magyarországi üzemekben
A vágópulyka-előállításnak napjainkban számos kihívással kell szembenéznie, amely a világgazdasági folyamatokból, valamint az állattartás nehézségeiből és biológiai sajátosságaiból fakad. Bár a pulykahús kedvező beltartalma és magas ásványianyag-tartalma miatt kedvelt fehérjeforrás, kereslete az elmúlt években – főként a HORECA (hotelek, éttermek, kávézók) szektor kiesése miatt –, globális szinten mérséklődött. Jelen tanulmányban a magyarországi pulykahús-előállító szakágazat üzemtani vizsgálatát tűztük ki célul. A kutatás során egy hazai, jó színvonalon gazdálkodó vágópulyka előállításával foglalkozó „virtuális üzemet” modelleztünk, amelyhez determinisztikus elven működő szimulációs modellt alkalmaztunk. A „virtuális üzem” lényegében az országban működő gazdaságok felső negyedébe tartozókat tükrözi, nem pedig az országos átlagot. A modellkalkuláció időhorizontja 2022. év elejére vonatkozik, így az eredmények is az akkori input és output árak mellett értelmezhetők. A rögzített feltételek mellett egy kilogramm élőpulyka előállításának költsége 575 forint volt a vizsgált időszakban. A termelési költségek közel 90%-át az anyagjellegű költségek jelentették, melyet a takarmány költsége határoz meg. A vágópulyka-előállítás termelési értéke egy kilogramm élősúlyra vetítve 479 forint volt, az ágazat számára elérhető horizontális támogatásokkal együtt. A modell alapján, a vizsgált gazdasági környezetben még jó színvonalú gazdálkodási körülmények között is veszteséges a vágópulyka előállítása. Jövedelmező tevékenységre magasabb élőállat felvásárlási árak vagy alacsonyabb költségek (pl. a takarmányárak visszarendeződése) esetében számíthatnak a termelők
The ontogenies of endometrial and myometrial leptin and adiponectin receptors in pregnant rats: Their putative impact on uterine contractility
α-Tocopherol Potentiates the Cervical Resistance Decreasing Effects of COX Inhibitors in Pregnant Rats: The Putative Role of Cyclooxygenase-2 Inhibition
Prediction of gastroesophageal reflux episodes by smooth muscle electromyography: A translational study in rats and adolescents
Soluplus® promotes efficient transport of meloxicam to the central nervous system via nasal administration
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