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W Reinhardt

Publications and source records attributed to W Reinhardt.

At least 55 records · Page 3Linked to original sources
PubMed1987

Thoracic peridural block in experimental endotoxin shock.

The influence of thoracic peridural block (PDB) on the metabolic and hemodynamic changes in endotoxin shock were investigated in rabbits. During the first 6 h of endotoxin shock, sensomotoric and sympathetic blockade distal to spinal segment T4 was achieved by intermittent administration of bupivacaine into a thoracic peridural catheter. The increase of plasma glucose, lactate, and free glycerol 2 h after endotoxin (50 micrograms/kg) administration was prevented by PDB. Animals with PDB had an accelerated clearance of glucose as indicated by a shorter plasma half-life of intravenously injected glucose (0.33 g/kg) 1 h after endotoxin administration. Hemodynamic parameters were measured during the first 210 min after endotoxin application. Compared with controls, PDB reduced mean arterial pressure and total peripheral resistance. PDB did not affect the initial increase of right ventricular pressure or the progressive decrease in O2 consumption and cardiac output after the endotoxin injection. The mortality at 24 h was not significantly reduced by the PDB (controls, n = 22: 68%; PDB, n = 21: 57%). The results demonstrate that thoracic PDB effectively blocks the sympathetic response in endotoxin shock. Hence, PDB causes peripheral vasodilatation, and, moreover, the metabolic data are consistent with an inhibition of the reactive glycogenolytic and lipolytic responses in shock. Although PDB altered the metabolic disturbances caused by endotoxin shock, mortality was not significantly affected.

Animals↗
PubMed1985

[Retrograde ejaculation, a little known complication of ectopic ureterocele with ureteral duplication].

A 9 year old boy with an ectopic ureterocele on a left ureteral duplication was treated by radical surgery: nephro-uretero-ureterocelectomy. At 22 years of age he presented with total absence of ejaculation, shown to be due to retrograde ejaculation from permanent gaping of bladder neck. Urinary affections were absent and urologic results of operation were good. The prevention of this disturbing genital complication, and the manner to treat it if it does develop, are discussed.

Child↗
PubMed1984

[The upper urinary tract in pregnant women. Physiopathologic, ultrasonic and urographic study].

This study of the upper urinary tract with the voluntary co-operation of expectant mothers, and based on 316 ultrasound examinations and 138 urographies, confirms the high incidence of uretero-pyelocalyceal dilatations is pregnancy. Compression by the gravidic uterus and the hormonal environment of pregnancy are the best-known etiologies. The frequency of associated urinary infections and the slow regression of the dilatation in the post-partum period (three months) will be noted.

Female↗
PubMed1983

An electrophysiological study of the accessory olfactory bulb in the rabbit--I. Analysis of electrically evoked potential fields.

Following electrical stimulation of the vomeronasal nerves, the primary olfactory nerves, the lateral olfactory tract and the corticomedial amygdala, we have made a study of evoked potentials in the rabbit accessory olfactory bulb. Vomeronasal nerve stimulation evoked a complex field potential consisting of a compound action potential followed by 4 negative waves (N1, N2, N3, N4). In contrast to the field potential elicited in the main olfactory bulb following primary olfactory nerve stimulation, there was either no evoked wave or only a weak positive component of the field in the accessory bulb. Amygdala stimulation caused a long latency, long duration negative-positive dipolar field potential in the accessory olfactory bulb. Both antidromic and orthodromic field potentials showed sign reversal when the electrode penetrated the bulb at a point corresponding to the lower border of the mitral cell band. Stimulation of the lateral olfactory tract elicited a weak, short-latency wave which did not show any sign reversal when the electrode was lowered into the accessory bulb. This wave was presumably due to fibres arising in the main bulb and projecting through the accessory bulb into the lateral olfactory tract. Electrical stimulation of the primary olfactory nerves did not induce any response in the accessory bulb neither did vomeronasal nerve stimulation evoke a response in the main olfactory bulb. The origin of these potential fields is discussed and it is concluded that the synaptic organization of the accessory olfactory bulb resembles that of the main olfactory bulb in lower vertebrates. There is no detectable communication between the two olfactory systems.

Amygdala↗
PubMed1983

An electrophysiological study of the accessory olfactory bulb in the rabbit--II. Input-output relations as assessed from analysis of intra- and extracellular unit recordings.

The input-output relations of the rabbit accessory olfactory bulb were studied by intra- and extracellular single unit recordings following electrical stimulation of the vomeronasal nerves, the lateral olfactory tract and the corticomedial amygdala. Cellular activity of accessory bulb mitral cells evoked by stimulation of the vomeronasal nerves consisted of a brief excitation with a latency of 16 ms. This initial response was followed by a period of reduced firing probability which was due to an inhibitory postsynaptic potential. In many cases this secondary response was followed by a second excitatory postsynaptic potential on which action potentials were generated at higher stimulus intensities. Deeper cells in the granule cell layer responded with a long latency, long duration, excitation, often consisting of bursts of 2-3 spikes. The majority of mitral cells were antidromically invaded by amygdala stimulation. The latencies of the antidromic spikes showed a wide range of variation (12-80 ms). Due to this great variation in antidromic latency the inhibitory postsynaptic potential following the antidromic action potential was rather modest but prolonged in duration. In many cases the onset of the inhibitory postsynaptic potential preceded the antidromic response. The majority of cells did not respond to lateral olfactory tract stimulation. Only 10% of the tested cells were invaded antidromically by stimulation at this site. These neurons were also driven antidromically by amygdala stimulation. We conclude that, although the physiological characteristics of mitral cells of the main and accessory olfactory bulb are very similar, there are important differences. The efferent fibres of the accessory bulb conduct at very slow and variable rates and project directly to the corticomedial amygdala.

Amygdala↗
PubMed1983

Induction of cytosolic progestin binding sites by catecholestrogens in rat pituitary gland and uterus: different potencies of 2- and 4-hydroxyestradiol.

The ability of catecholestrogens to induce cytosolic progestin binding sites in the hypothalamus, pituitary gland, and uterus of ovariectomised-adrenalectomised rats was demonstrated by the increase in high-affinity [3H]promegestone binding sites (KD 1.39, 0.50, and 0.54 nM, respectively) following a single subcutaneous injection (26.4 micrograms/animal) of the 3.4-dibenzoate ester of 4-hydroxyestradiol. The affinity and the time course of induction of these binding sites were very similar to those after a single injection of an equivalent dose (20 micrograms/animal) of estradiol 3-benzoate, exhibiting maximal receptor levels after 44 h. Widely differing efficacies in the induction of progestin binding sites were observed between the dibenzoate esters of 2- and 4-hydroxyestradiol. 2-Hydroxyestradiol 2,3-dibenzoate was ineffective in the pituitary gland up to a dose of 132 micrograms/animal, whereas 4-hydroxyestradiol dibenzoate was equipotent to estradiol benzoate, showing a maximal induction of progestin binding sites at single doses in the range of 13.2-26.4 micrograms/animal (equivalent to 10-20 micrograms of estradiol benzoate). As compared to the pituitary gland, the uterus was much more sensitive to the systemic administration of estrogen benzoates. At single doses in the range of 1.32-6.6 micrograms/animal (equivalent to 1-5 micrograms of estradiol benzoate), 4-hydroxyestradiol dibenzoate induced maximal levels of progestin receptors, and even 2-hydroxyestradiol dibenzoate, when given at a high dose (132.4 micrograms/animal, equivalent to 100 micrograms of estradiol benzoate), produced a slight increase in progestin binding sites.

Adrenalectomy↗
PubMed1981

Electrophysiology of olfacto-limbic-hypothalamic connections in the pig.

To analyse fibre connections between the olfactory bulb (OB) and limbic-hypothalamic structures, the lateral olfactory tract (LOT) was stimulated electrically and extracellular action potentials were recorded from single units in the OB, the cortico-medial portion of the amygdala (AMY) and the mediobasal hypothalamus (MBH). More than 29% of the antidromically identified mitral cells in the OB showed a spontaneous episodic firing pattern consisting of alternating periods of activity and inactivity. Nearly 14% of the orthodromically excited non-mitral cells showed the same phasic firing pattern. 2.9% of AMY neurons were antidromically activated by LOT stimulation, whereas more than 52% showed orthodromic responses. In contrast to the AMY no neuron in the MBH could be antidromically invaded by electrical stimulation. The incidence of orthodromic responses was much less in the MBH when compared to the AMY (13.5%). It is concluded that the firing pattern of OB cells in the pig is complex, often phasic and unrelated to respiration or sniffing. The main OB is more closely related to the AMY than to the MBH. It is suggested that olfactory information is probably transmitted to the MBH via the AMY. The AMY may play a role in the regulation of OB activity.

Amygdala↗