The awareness of the scared - context dependent influence of oxytocin on brain function

Brain Imaging and Behavior - Oxytocin is both a hormone and a neurotransmitter and has been originally recognized for its role in childbirth and lactation. Later, it became widely known as a...     

Dieulafoy's disease: endoscopic treatment and follow up.

The findings from 480 patients who had emergency endoscopy for acute upper gastrointestinal bleeding of non-variceal origin at our institution were analysed. Twenty eight patients (5.8%) had a Dieulafoy lesion. In 27 patients (96.4%) bleeding could be successfully managed by injection of norepinephrine and polidocanol, in repeated sessions if needed. Two patients had to be treated surgically: one because of uncontrollable bleeding from the Dieulafoy lesion and one despite endoscopic control of the bleeding Dieulafoy lesion because of a concomitant bleeding from an anastomosal ulcer after gastric resection. Three patients died during hospital stay from causes unrelated to bleeding from Dieulafoy lesion. Out of the 25 patients discharged from the hospital 21 treated by endoscopy and two treated with surgery were followed up for a mean of 28.3 and 22.5 months, respectively. Twenty endoscopically treated patients (95%) had no recurrence of Dieulafoy's bleeding. One patient experienced severe rebleeding from the original site after a transient endoscopy confirmed complete disappearance. He had emergency operation without a further attempt to control bleeding by endoscopy. It is concluded that bleeding from Dieulafoy's disease can be successfully managed by endoscopic injection treatment. The longterm outcome is favourable.     

Acquisition of DRL-20 behavior in male and female, Roman high- and low-avoidance rats

Female RLA rats were more efficient than male RLA, male and female RHA rats (in that order), in the acquisition of DRL-20 operant conditioning behavior. It was concluded that RHA rats were less capable of inhibiting nonrelevant activity in that test.     

Effects of insulin and 2-deoxy-D-glucose on plasma glucose level and lateral hypothalamic eating threshold in the rat

Thresholds for elicited eating through monopolar electrodes in the perifornical region of the lateral hypothalamus and plasma glucose concentration were determined over periods of several hours, while blood glucose levels and cellular glucose utilization were altered by means of forced feeding through hypothalamic stimulation, subcutaneous insulin injections and/or intraperitonneal 2-deoxy-D-glucose injections. Forced feeding resulted in increased thresholds for elicited eating, whereby the plasma glucose concentration in the tail vein was positively correlated to these thresholds. A subsequent, long-lasting, severe insulin-hypoglycemia was not sufficient to normalize such elevated thresholds. However, 2-deoxy-D-glucose in doses of 100–250 mg/kg, after an initial increase, decreased thresholds 90 min after injection. When insulin and 2-deoxy-D-glucose were combined so as to balance the contrary glycemic effects, the insulin effect dominated, resulting in slightly increasing thesholds. The results are discussed in terms of the recently suggested hypothesis that insulin regulates glucose entry into glucosensitive systems of the ventromedial hypothalamus, and thus generates satiety signals rather than hunger.     

The effect of ambient temperatures on eating elicited by hypothalamic stimulation

Rats were implanted with electrodes in the perifornical lateral hypothalamic area. The amount of stimulus-bound-eating (SBE) was defined as the number of pellets eaten during ten consecutive trains of 60 sec stimulation, separated by intervals of 30 sec at a previously fixed stimulus intensity. The effect of increased ambient temperature (39°C) was studied in a group of eight animals and the effect of lowered ambient temperatures in a different group of eleven animals. A significant decrease of SBE as compared to the 24°C control condition was found after 30 min of exposure to 39°C and a significant increase after 90 min of exposure to 9°C. These differences were maintained with repetitive alternate exposures of 180 min to the control and experimental temperature conditions. These exposures did not produce any differential effects on colonic temperatures. After termination of the exposure to both elevated and lowered ambient temperature, SBE returned to control levels within short intervals of 10–20 min.     

Environmental and genetic effects on food-deprivation induced stomach lesions in male rats

When Roman high- and low-avoidance (RHA/Verh and RLA/Verh) rats were individually housed in plastic cages with sawdust bedding and food-deprived (F-D) for 4–5 days, it was found that F-D RHA/Verh rats had more lesions than their unfasted controls and more lesions than F-D RLA/Verh rats. The lesions were mostly petechial in nature and located in the glandular portion of the stomach. Also, F-D RHA/Verh rats which were housed in the same room as the controls, as well as F-D RHA/Verh rats which were housed in a separate room with a strong food odor present, had more lesions than F-D RHA/Verh rats housed in the same separate room when there was no food odor, and when none of the rats present had access to food. When F-D RHA/Verh and F-D RLA/Verh rats were individually housed in metal cages with grid floors, however, a general increase in lesion scores resulted and differences between the two rat lines disappeared, as did differences among the room conditions. Also, many lesions were of an ulcerative nature and were located in the rumenal portion of the stomach. It was concluded that sensory (in this case olfactory, at least) and genetic factors are capable of playing roles in the induction of stomach lesions in rats, and that the type, extent and location of the lesions can depend upon whether or not the animals have access to sawdust bedding.     

Tricyclic antidepressant plasma levels after augmentation with citalopram: a case study

Summary In a depressed patient, the addition of citalopram 40–60 mg per day to treatment with amitriptyline 75 mg per day had no effect on the plasma levels of amitriptyline and nortriptyline, but it led to clinical improvement without the appearance of adverse effects.This and similar findings in four other patients comedicated with citalopram and amitriptyline (2 patients), clomipramine or maprotiline suggest that citalopram differs from other selective serotonin reuptake inhibitors, such as fluvoxamine and fluoxetine, which have been shown to increase tricyclic antidepressant plasma levels.     

Dextromethorphan and mephenytoin phenotyping of patients treated with thioridazine or amitriptyline.

The metabolism of most tricyclic antidepressants and some phenothiazine neuroleptics is under the genetic control of hepatic cytochrome P-450IID6, which also regulates the metabolism of dextromethorphan. This study investigated the effect of treatment with amitriptyline or thioridazine on testing for genetically regulated efficiency of the metabolism of dextromethorphan and mephenytoin. One group of 33 patients was treated with 150 mg amitriptyline a day (the AMI group); 25 other patients received a daily dose of thioridazine, either 200 mg (200-THD group; n = 7) or 400 mg (400-THD group; n = 18). Before and after 10 days of this treatment, all patients were tested with 25 mg dextromethorphan and 100 mg mephenytoin to determine their pharmacogenetic status with respect to their hepatic drug oxidizing systems (cytochrome P-450IID6 and P-450 MP). Two patients were poor metabolizers (PMs) of dextromethorphan and three of mephenytoin. Treatment with either psychotropic drug was without significant effect on the metabolism of mephenytoin, but both amitriptyline and thioridazine increased significantly the metabolic ratio of dextromethorphan/dextrorphan. Thioridazine had the effect of changing the pharmacogenetic status of 15 efficient metabolizers of dextromethorphan to poor metabolizers; amitriptyline did not have such an effect. There was no significant correlation between day-11 plasma levels of thioridazine, mesoridazine, or sulforidazine and the metabolism of dextromethorphan, but there was a correlation between the metabolism of dextromethorphan and plasma levels of amitriptyline and nortriptyline. Amitriptyline (p less than 0.05), but not thioridazine, decreases the ratio of conjugated/total dextrorphan in urine.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of nicotine on the visual evoked response

The effects of smoking cigarettes differing in nicotine content (0.14 vs 1.34 mg/cigarette) on the peak-to-peak amplitude and peak latency of the human averaged visual evoked response (AVER) were measured in 10 male smokers after a 2-hr smoking deprivation period. The AVER was obtained under five different flash intensities. Eight different peaks were involved in the amplitude and latency measurements. The nicotine dosage and flash intensity factors both had significant effects on peak-to-peak amplitudes while only the flash intensity factor affected peak latencies. The general enhancement of peak-to-peak amplitudes by the 1.34 mg cigarette, relative to the 0.14 mg cigarette, indicates that the effects of cigarette smoking on the AVER are predominantly due to nicotine's psychopharmacologic action, as opposed to other elements in tobacco smoke or as opposed to nonpharmacologic mechanisms involving learning processes. Past research, on an electrophysiological and behavioral level, indicating that nicotine, as administered via cigarette smoking, may have enhancing and/or restorative effects on visual attentional processes in the quiescent smoker was supported.