Search results for "pine"
showing 10 items of 2022 documents
Autoinhibition of noradrenaline release from the rat heart as a function of the biophase concentration. Effects of exogenous alpha-adrenoceptor agoni…
1984
1. Rat isolated perfused hearts with the right sympathetic nerves intact were loaded with 3H-(-)-noradrenaline. The nerves were stimulated with trains of 180 pulses at 3 Hz and at 10 min intervals. The overflow of 3H-noradrenaline and 3H-metabolites was determined by liquid scintillation spectrometry. 2. Clonidine (IC50 17 nM), oxymetazoline (IC50 63 nM), and α-methylnoradrenaline (apparent IC50 35 nM, determined in the presence of cocaine and propranolol) decreased the stimulation-evoked overflow of 3H-noradrenaline by 26, 49, and 78%, respectively, but not methoxamine up to 100 μM (propranolol present). Oxymetazoline and α-methyl-noradrenaline did not cause desensitization of the presynap…
Voltage-Dependent Effects of Barnidipine in Rat Vascular Smooth Muscle
2003
The effects of the dihydropyridine nifedipine and its more lipophilic congener, barnidipine, were investigated in smooth muscle preparations from the rat in resting and depolarizing conditions. Both drugs relaxed precontracted aortic rings more potently in depolarizing conditions, barnidipine being more potent than nifedipine. Currents through Ca 2+ channels in rat vascular smooth muscle cells (A7r5) and in isolated rat cardiomyocytes were reduced more potently by both drugs at a holding potential of-40 mV than at -80 mV. However, barnidipine and nifedipine were more effective in reducing the current in A7r5 cells than in cardiomyocytes. The IC 50 obtained in aortic rings and in A7r5 cells …
Survey on Current Postnatal Surgical Management of Myelomeningocele in Germany.
2016
Background and Study Aims Although postnatal surgery can be regarded as the standard of care for open myelomeningocele (MMC), there is no uniform treatment for this condition in Germany. This study assessed the current situation regarding the management of open MMC, a first and essential step toward the development of standards of practice. Patients and Methods In the second half of 2009, we had sent standardized questionnaires to 139 neurosurgery departments and 73 pediatric surgery departments (number of returned questionnaires: 98 and 62, respectively) to identify the principles of MMC management. Newborns with open MMC are treated in 57 of the neurosurgery departments and in 18 of the…
Evidence for the presence of two 24-h rhythms 180 degrees out of phase in the pineal gland of male Pirbright-White guinea pigs as monitored by counti…
1987
Previous studies have shown that the "synaptic" bodies of mammalian pinealocytes are a heterogeneous group of organelles. Whereas "synaptic" ribbons (SR) exhibit a day/night rhythm with small numbers during daytime and high numbers at night, the so-called "synaptic" spherules (SS) show species-specific differences in their rhythmicity. In the present study the numbers of SR and SS were monitored in male guinea pigs over a full 24-h period at 4-hourly intervals (LD 12:12, lights on at 7:00). The results obtained show that the rhythms of SR numbers and SS numbers are out of phase by 180 degrees. SR numbers are small during daytime and high at night, whereas SS numbers are high during daytime …
Day-night rhythm of acetylcholine in the rat pineal gland
1997
Abstract Using high-performance-liquid-chromatography (HPLC) measurement of acetylcholine, choline acetyltransferase (ChAT) enzyme assay and anti-ChAT immunohistochemistry, we have investigated the expression of the cholinergic system in pineal glands of male rats. Glands procured during the day period (1200 h) contained significant amounts of acetylcholine (0.5 pmol/gland). A similar content was found in pineal glands after a 48 h culture period, i.e. when the intrapineal nerve fibres have degenerated. This strongly indicates that the pinealocytes are the cells which contain acetylcholine. To confirm this conclusion we demonstrate substantial ChAT-like immunoreactivity in pinealocytes. ChA…
Transcriptional regulation of nucleoredoxin-like genes takes place on a daily basis in the retina and pineal gland of rats.
2015
AbstractThe nucleoredoxin-like gene Nxnl1 (Txnl6) and its paralogue Nxnl2 encode the rod-derived cone viability factors (RdCVF and RdCVF2), which increase the resistance to photooxidative damage and have therapeutic potential for the survival of cones in retinitis pigmentosa. In this study, the transcription of Nxnl genes was investigated as a function of the day/night cycle in rats. The transcript levels of Nxnl1 and Nxnl2 were seen to display daily rhythms with steadily increasing values during the light phase and peak expression around dark onset in preparations of whole retina, photoreceptor cells and—but only in regard to Nxnl1—in photoreceptor-related pinealocytes. The cycling of Nxnl…
Presynaptic effects of scopolamine, oxotremorine, noradrenaline and morphine on [3H] acetylcholine release from the myenteric plexus at different sti…
1987
The inhibition by three modulators (oxotremorine, noradrenaline, morphine) of acetylcholine release from the myenteric plexus preincubated with [3H]choline was investigated at different stimulation frequencies and calcium concentrations. Moreover, [3H]acetylcholine release evoked by a low (0.1 Hz) or a high (10 Hz) stimulation rate was investigated at different calcium concentrations either in the absence or presence of scopolamine. A reduced calcium concentration (0.6 mmol/l) inhibited acetylcholine release more at 0.1 Hz (74% +/- 3%) than at 10 Hz (44% +/- 8%). Scopolamine enhanced the stimulated acetylcholine release at a calcium concentration of 1.8 mmol/l. At calcium concentrations hig…
The effect of physostigmine on the vagally induced muscarinic inhibition of noradrenaline release from the isolated perfused rabbit atria.
1982
1. Presynaptic cholinergic-adrenergic interactions were studied on isolated perfused rabbit atria with the extrinsic right vagus and sympathetic innervation intact. The transmitter stores were labelled with 14C-choline and 3H-noradrenaline. The radioactive compounds were separated on columns and determined by scintillation spectrometry. The stimulation-evoked overflow of both transmitters was calcium-dependent and abolished by tetrodotoxin. 2. Methacholine caused a concentration-dependent decrease of atrial tension development and 3H-noradrenaline overflow evoked by 3 Hz sympathetic stimulation. Vagus nerve stimulation (1–20Hz), although nearly abolishing tension development at 20Hz, decrea…
The role of choline in the release of acetylcholine in isolated hearts.
1978
1. The concentrations of acetylcholine, choline and noradrenaline were estimated in the perfusate (overflow) of isolated hearts of chickens, cats, rabbits and guinea pigs. Neurotransmitter release was evoked by stimulation of both vagus nerves and by direct stimulation of the heart (field stimulation). 2. In the absence of exogenous choline and physostigmine, field stimulation at 20 Hz for 20 min caused an overflow of acetylcholine from the hearts of the 4 species investigated. During vagal stimulation, however, acetylcholine was detected only in the perfusate of the chicken heart. 3. Field stimulation for 2 min caused an overflow of 193 pmol g−1 min−1 acetylcholine and of 666 pmol g−1 min−…
Metabolic Syndrome and Vitamin D Levels in Patients with Obstructive Sleep Apnea Syndrome
2018
Numerous studies have indicated that obstructive sleep apnea syndrome (OSAS), may contribute to the development of metabolic syndrome (MetS) and diabetes. Moreover, OSAS has been associated with lowered vitamin D (Vit D) levels, but reports are inconclusive. Aim of the study was to compare Vit D levels according to the presence of MetS and its components in OSAS patients.The presence of MetS was evaluated and serum 25-hydroxy vitamin D [25(OH)D] levels were measured in consecutive newly diagnosed, by polysomnography, subjects with OSAS.A total of 107 subjects (88 men) with OSAS were included in the study. Patients were divided into group A (OSAS with MetS group: 55 subjects) and group B (OS…