Efficacy and tolerability of potato juice in dyspeptic patients: a pilot study.

In Europe, use of potatoes (Solani tuberosi tuberecens) is a traditional remedy for stomach complaints. We performed a pilot study on the effectiveness and tolerability of freshly squeezed potato juice in patients suffering from dyspeptic symptoms. After informed written consent, 44 patients with various dyspeptic symptoms were enrolled, to drink for 1 week twice daily 100ml or more of potato juice (Biotta, if complaints persisted, a further 100ml was recommended. Validated outcome measures included the gastrointestinal symptom (GIS) profile, a disease-specific health assessment questionnaire (QOLRAD) and self-rated treatment success (efficacy, a 5-point Likert Scale). The study was completed by 42 patients. The GIS and QOLRAD scores improved significantly by 41.9+/-40.8% (p=0.001) and 50.7+/-36.1% (p<0.001), respectively (ITT); the absolute values changed from 11.5+/-5.1 to 6.3+/-5.3 (GIS) and 62.0+/-25.7 to 32.0+/-28.8 (QORAD). Sixteen, 18 and 26 patients, respectively, rated the effectiveness of the treatment as very good or good on the GIS, QOLRAD (improvements >60%) and on efficacy, respectively. Poor treatment success was achieved in 13 (GIS), 11 (QOLRAD) and 10 (Efficacy), not necessarily by the same patients. Since about two-thirds of the patients benefited to some extent from the treatment, potato juice in its present formulation may be useful for self-treatment. However, placebo-controlled studies with a longer treatment period are needed to confirm this.

Effect of the anesthetic agent propofol on hormonal responses to ECT.

Propofol is a new anesthetic induction agent that reduces electroconvulsive therapy (ECT) seizure duration. To indirectly investigate the effect of propofol on ECT-induced acute central neurotransmitter changes, we studied neuroendocrine responses in 25 primary depressed subjects treated with ECT under either propofol or thiopentone anesthesia. Blood samples were taken prior to ECT, and then at regular intervals for 2 hr. Only the prolactin response correlated significantly with seizure duration (r = 0.52, p less than 0.01). Subjects given propofol had significantly reduced adrenocorticotropin (ACTH) (p less than 0.01) and cortisol (p less than 0.05) responses compared to thiopentone, which were independent of seizure duration. There was a trend towards a reduction in the prolactin response with propofol compared to thiopentone, but this was dependent upon the diminished seizure duration. The results indicate that propofol affects endocrine responses to ECT by two distinct mechanisms: decreasing prolactin by reducing the seizure duration and decreasing ACTH and cortisol by another process, possibly via a reduction in central noradrenergic activation.

Effect of corticosterone treatment and adrenalectomy on phenylethanolamine N-methyltransferase and catecholamines in brain stem and hypothalamic nuclei and superior cervical ganglion of rats.

The effects of corticosterone treatment and adrenalectomy with or without corticosterone replacement on the activity of phenylethanolamine N-methyltransferase (PNMT) and catecholamine content has been studied in isolated brain stem nuclei containing adrenergic and noradrenergic nerve cell bodies, hypothalamic nuclei and in the superior cervical ganglion (SCG) of adult rats. Changes of PNMT activity were found only in a few brain stem areas. In adrenalectomized rats, PNMT activity was decreased in Cl area and in the locus coeruleus, but after corticosterone replacement it returned to the control values. The treatment of rats with corticosterone resulted in a rise of PNMT activity only in C2 area. No significant changes in PNMT activity were seen in the hypothalamic areas in any experimental group of rats. The observed changes of PNMT activity occurred without any measurable changes of noradrenaline (substrate) or adrenaline (product of the reaction catalysed by PNMT). Our results may suggest the involvement of brain stem adrenaline and noradrenaline producing neurons in the central modulation of the pituitary-adrenal function. The basal PNMT activity in SCG of adult rats was very low, but the treatment of rats with high dose of corticosterone or corticosterone replacement to adrenalectomized rats increased PNMT activity in the SCG to the same extent.

A radiometric assay for phenylethanolamine N-methyltransferase and catechol O-methyltransferase in a single tissue sample: application to rat hypothalamic nuclei, pineal gland, and heart.

A simple and highly sensitive method for simultaneous assay of phenylethanolamine N-methyltransferase (PNMT) and catechol O-methyltransferase (COMT) is described. These enzymes are determined in a single tissue homogenate using S-[methyl-3H] adenosyl-L-methionine as methyl donor and sequentially incubating with the substrates phenylethanolamine and epinephrine. The radioactive products of the enzymatic reactions, N-methylphenylethanolamine and metanephrine, are extracted and then separated by thin-layer chromatography. The identity of the reaction products has been established chromatographically and the conditions for both enzymatic reactions in the assay procedure have been defined. Measurement of PNMT activity in the rat pineal gland or in minute fragments of other tissues (e.g., brain nuclei) has not been possible using previously described methods. Activities of PNMT and COMT in the rat pineal gland, various hypothalamic nuclei, and the auricular and ventricular myocardia are herein reported.

Relationship of train-of-four ratio to twitch depression during pancuronium-induced neuromuscular blockade.

The relationship of train-of-four (TOF) ratio to the depression of the first twitch (TD) was investigated in 16 patients given pancuronium in doses insufficient to eliminate the fourth response in the train. In ten patients the block was allowed to spontaneously recover (Group 1) and in six it was reversed with neostigmine (Group 2) once maximum depression of TOF ratio had occurred. Maximum depression of the first response occurred in 6.5 +/- 4.3 min (mean +/- SD). Maximum depression of the TOF ratio was not present until 28.0 +/- 11.0 min. TOF ratio was usually still decreasing when recovery of TD had begun. However, once the TOF ratio began to recover, the recovery rates for TD and TOF ratio were similar in both the spontaneously recovering and the reversed groups. TOF ratio at complete TD recovery was 74.9 +/- 15.7 and 86.2 +/- 15.4% for the two groups. A kinetic analysis yielded significantly different elimination rate constants for the two effects from the "effect compartment." These findings suggest that these two effects of pancuronium are exerted at different sites.

Effect of repeated immobilization stress on central and peripheral adrenoceptors in rats.

Repeated forced immobilization stress (40 times for 2.5 h daily) reduced the number of beta-receptors in the heart, hypothalamus and brain stem, but not in the spleen of rats. Repeated immobilization stress has also been found to decrease the number of alpha1-receptors in the heart and increase the number of alpha2-receptors in the spleen and brain stem, as compared to control unstressed rats. The number of heart alpha1-, spleen and brain stem alpha2-receptors was still decreased or increased, respectively, 24 h after the 39th immobilization stress. However, at the same time the number of beta-receptors in the heart and brain stem returned to the control levels. We concluded, that the changes in the number of rat adrenoceptors in the heart, hypothalamus and brain stem correlate with peripheral catecholamines released during repeated immobilization stress.

Catecholamines and their enzymes in discrete brain areas of rats after space flight on biosatellites Cosmos.

The activity of the catecholaminergic system was measured in the hypothalamus of rats which had experienced an 18.5-19.5-day-long stay in the state of weightlessness during space flights on board Soviet biosatellites of the type Cosmos. In the first two experiments, Cosmos 782 and 936, the concentration of norepinephrine and the activities of synthesizing enzymes tyrosine hydroxylase and dopamine-beta-hydroxylase and of the degrading enzyme monoamine oxidase were measured in the total hypothalamus. None of the given parameters was changed after space flight. In the light of the changes of these parameters recorded after exposure to acute stress on Earth, this finding indicates that long-term state of weightlessness does not represent an intensive stressogenic stimulus for the system studied. In the space experiment Cosmos 1129, the concentration of norepinephrine, epinephrine, and dopamine was studied in isolated nuclei of the hypothalamus of rats within 6-10 hr following return from space. Norepinephrine was found to be significantly reduced in the arcuate nucleus, median eminence and periventricular nucleus, epinephrine in the median eminence, periventricular and suprachiasmatic nuclei, whereas dopamine was not significantly changed after space flight. The decreased catecholamine levels found in some hypothalamic nuclei of rats which had undergone space flight indicate that no chronic intensive stressor could have acted during the flight, otherwise the catecholamine concentration would have been increased in the nuclei. The decreased levels must have been induced by the effect of a stressogenic factor acting for a short time only, and that either during the landing maneuver or immediately after landing. Thus long-term exposure of the organism to the state of weightlessness does not represent a stressogenic stimulus for the catecholaminergic system in the hypothalamus, which is one of the regulators of the activation of neuroendocrine reactions under stress.

[Noradrenaline and the enzymes of its synthesis and breakdown in the rat hypothalamus after a flight on the Kosmos-936 biosatellite]. / Noradrenalin i fermenty ego sinteza i raspada v gipotalamuse krys posle poleta na biosputnike "Kosmos-936".

In the hypothalamus of the weightless and centrifuged rats flown for 18.5 days on board the biosatellite Cosmos-936 the noradrenaline concentration and activity of the enzymes involved in the catecholamine synthesis and degradation were measured. It was found that under the space flight influence the noradrenaline concentration and tyrosine hydroxylase, dopamine-beta-hydroxylase and monoamine oxidase activities remained unaltered. These findings indicate that a prolonged exposure to weightlessness was not a stressogenic agent that could activate the adrenergic system in the rat hypothalamus.

Mepacrine treatment prevents immobilization-induced desensitization of beta-adrenergic receptors in rat hypothalamus and brain stem.

Forced immobilization is a severe stress in rats which diminishes levels of epinephrine in specific nuclei in the hypothalamus and brain stem, suggesting that release of epinephrine is stimulated to a rate which exceeds the rate of its replacement. In the pineal gland, frog erythrocytes, C6 astrocytoma cells and rat brain, beta-adrenoceptor agonists appear to regulate the number of their receptors. Exposure to high concentrations of an agonist leads to apparent decrease in receptors reflected by a decrease in maximal specific binding of antagonists. The apparent decreases in receptors have been shown to be attended by decreases in physiologic responsiveness. In C6 astrocytoma cells, beta-agonists stimulate methylation of phosphatidylethanolamine to increase formation of membrane phosphatidylcholine which in turn appears to enhance activation of adenyl cyclase. Interference with the metabolism of phospholipids by exposure to phospholipase A2 inhibitor, mepacrine (quinacrine), prevents agonist-induced desensitization of beta-adrenoceptors in astrocytoma cells. In the present study repeated immobilization stress has been found to decrease significantly the number of beta-adrenoceptors in hypothalamus and brain stem while increasing the number of alpha 2-adrenoceptors. The desensitization of beta-adrenoceptors was prevented by treatment with mepacrine.

Increased brain stem and decreased hypothalamic adrenaline-forming enzyme after acute and repeated immobilization stress in the rat.

The effects of immobilization stress on the activity of the adrenaline-forming enzyme, phenylethanolamine N-methyltransferase (PNMT), have been studied in discrete areas of the rat brain stem and hypothalamus. The changes in brain PNMT activity varied with the duration of the stress, were localized to a few brain areas, and the direction of the change varied with the area considered. PNMT was increased after acute immobilization in several areas of the brain stem: A2 area, the anterior part of the nucleus tractus solitarius, and the locus coeruleus. After 7 days of stress, significantly increased PNMT activity was found only in the A2 area and in the cerebellum. In the anterior hypothalamic nucleus, immobilization stress repeated for seven days resulted in a significant decrease in methyltransferase activity. These results implicate discrete, localized adrenaline-forming neurons in the central regulation of the stress response.

[Catecholamines and their metabolic enzymes in the hypothalamus of rats after a flight on the Kosmos-782 biosatellite]. / Katekholaminy i fermenty ikh obmena v gipotalamuse krys posle poleta na biosputnike "Kosmos-782".

The concentration of catecholamines, and activity of enzymes involved in their synthesis (tyrosine hydroxylase and dopamine-beta-hydroxylase) and degradation (monoamine oxidase) were measured in the hypothalamus of rats flown for 19.5 days aboard the biosatellite Cosmos-782, synchronous and vivarium controls sacrificed on R+O and R+25 days. No significant changes in the above parameters of the flight rats were found. The findings give evidence that a prolonged space flight induces no changes in the content, synthesis or degradation of catecholamines in the rat hypothalamus. This seems to indicate that weightlessness does not act as an acute stressor.

Catecholamines in individual hypothalamic nuclei of acutely and repeatedly stressed rats.

Norepinephrine (NE) and dopamine (DA) concentrations in 17 individual hypothalamic nuclei and 3 other brain regions were measured in rats, acutely or repeatedly stressed by immobilization, using a microdissection technique and a radioisotopic-enzymatic assay. Following the first 20 min immobilization (IMO) a significant NE decrease in the ventromedial (NVM) and supraoptic (NSO) nuclei and a DA decrease in the arcuate nucleus (NA) as well as NE and DA increase in the dorsomedial nucleus (NDM) were seen. Repeated IMO (40 times) produced a NE increase in the NVM, NDM, NSO paraventricular nucleus (NPV) and median eminence (ME), and a DA increase in the NDM and NPV. Changes of NE and DA concentration found in some individual hypothalamic nuclei under the influence of stress indicate that catecholamines (CAs), particularly in the medial basal hypothalamus, could be involved in the regulation of some neuroendocrine processes which are being activated during stress, especially ACTH release.