PubMed Health⌕ Search

Biomedical subjects

E Pósch

Publications and source records attributed to E Pósch.

At least 19 recordsLinked to original sources
PubMed1991

Effect of denervation on the neurogenic inflammation of the rat mandibular mucosa.

Effects of local exposure to capsaicin on the vascular permeability and blood flow were studied in the rat oral mucosa at days 2 and 14 after the unilateral transection of the inferior alveolar nerve (IAN). The distribution of nerve fibers displaying substance P (SP) and calcitonin gene-related peptide (CGRP) immunoreactivity (IR) in the mandibular mucosa was also assessed. While the capsaicin-induced augmentation in vascular permeability was about 50% (P less than 0.05) higher on the intact side (at both days 2 and 14) than on the denervated side, no difference in blood flow elevation was seen between the two sides. Transection of IAN caused only a slight reduction in the density of SP- and CGRP-IR fibers in the mucosa. It is concluded that in addition to the IAN fibers the mandibular mucosa examined also seems to be supplied by other sensory fibers. The presence of accessory trigeminal branches was also supported by immunohistochemical studies.

Animals↗
PubMed1991

Role of histamine in the development of neurogenic inflammation of rat oral mucosa.

The mechanism of development of neurogenic inflammatory reaction induced by the topical application of capsaicin was studied in the oral mucosa of rats with or without histamine antagonist pretreatment. The existence of a cholinergic component of the vasodilation was investigated using a muscarinic receptor antagonist. Results indicated that the neurogenic inflammatory increases in vascular permeability and blood flow are mediated in part by H1-receptors, H2-receptors and cholinergic pathways are apparently not activated in these processes.

Animals↗
PubMed1991

[The role of histamine in neurogenic inflammations of the mouth mucosa in rats].

The effect mechanism of neurogen inflammation incited by local capsaicin irritation was examined by the authors in the oral soft tissue of rats subsequent to antihistamin pretreatment. Furthermore, with the aid of muscarin blocking receptor also the parasympathetic component of the vasodilatation was examined. On basis of their results it was established that the vein-wall-permeability and microcircular changes observed in the course of the neurogen inflammation of the oral soft tissue partly expanded by the histamin through the H1-receptors. The H2-receptors as well as the parasympathetic fibers do not become activated in the process.

Animals↗
PubMed1991

[The effect of the transsection of the inferior alveolar nerve on neurogenic inflammation of the mouth mucosa. II. Immunohistochemical studies].

The distribution of nerve fibers displaying calcitonin gene-related peptide (CGRP) immunoreactivity in the mandibular mucosa was studied in control rats, in rats after unilateral transection of the inferior alveolar nerve (IAN), and in animals following cervical sympathetic denervation. According to the results, the transection of the peripheral branch of the IAN has no effect on the distribution of the CGRP immunoreactive nerves.

Animals↗
PubMed1991

[The effect of transsection of the inferior alveolar nerve on neurogenic inflammation of the oral mucosa. I. Functional studies].

Vascular effects of local capsaicin treatment has been studied on the 2nd and 14th days subsequent to unilateral inferior alveolar nerve (IAN) transection in the oral mucosa of rats. The results suggest, that the symptoms of neurogenic inflammation were influenced by the transection of IAN in a different way. The reason of that is the different mechanism in the development of the symptoms and/or the different compensatory capacity of the accessorial nerves.

Animals↗
PubMed1990

Experimentally-induced neurogenic inflammation in the rat oral mucosa.

Blood flow and vascular permeability in the gingiva and alveolar mucosa of the lower jaw were studied after the antidromic (electric) or orthodromic (topical administration of capsaicin onto the oral mucosa) stimulation of the inferior alveolar nerve (IAN) in rats with or without capsaicin pretreatment. Blood flow was determined using 86Rb isotope dilution technique, while vascular permeability was assessed by the Evans blue extravasation. Both antidromic or orthodromic stimulation of the IAN increased blood flow and Evans blue extravasation. Capsaicin pretreatment abolished the increase in gingivo-mucosal blood flow and vascular permeability induced by nerve stimulation. The results of the present study appear to confirm the possibility of the development of neurogenic inflammation in the oral cavity. The mechanism observed may play a role in the development of certain inflammatory reactions in the oral mucosa frequently encountered in human clinical practice.

Animals↗
PubMed1985

Diuretic and natriuretic actions of extract prepared from rat erythrocytes.

Freeze-dried preparation of rat erythrocytes was extracted into distilled water and after heat treatment the extract was chromatographed on Sephadex G-25 column. The effluent fractions were pooled, freeze-dried, dissolved in Ringer's solution and bioassayed for diuretic and natriuretic responses in anaesthetized non-diuretic rats. The active fractions potently enhanced urine output (about 9-fold control) and urinary sodium excretion (about 7-fold control). The responses started to develop after a lag period of approximately 10-20 min, peaked between 60-80 min post-injection and then diminished. The augmentation of sodium excretion persisted longer than the increased diuresis. The biological activity of the extract was retained after dialysis in a tube with nominal molecular weight cut-off below 1,000.

Animals↗
PubMed1985

Effect of indomethacin on the bradykinin-induced vasodilation in the submandibular gland.

Effects of the local infusion of bradykinin or isoproterenol were studied on the systemic blood pressure, blood flow, and vascular resistance of the submandibular gland before and after indomethacin treatment in cats. Both bradykinin and isoproterenol were shown to potently increase the glandular perfusion rate. The systemic arterial blood pressure fell by about 20% in response to indomethacin. The enhancement of blood flow by bradykinin or isoproterenol was not, however, affected by indomethacin treatment. The present results appear to suggest that the endogenous prostaglandins are not essentially involved in the development of responses produced by bradykinin or isoproterenol in the cat submandibular gland.

Animals↗
PubMed1985

Myasthenia gravis: long-term prognostic value of thymus lactate dehydrogenase isoenzyme pattern of hyperplastic thymus and thymoma.

Lactate dehydrogenase (LDH) isoenzyme pattern and the percent of H-subunit content were determined in the thymus of 62 patients (55 with hyperplasia, 7 with tumours) after thymectomy. An increase in LDH1 relative activity indicates that in the thymus of patients with myasthenia gravis the ratio of mature differentiated thymocytes was higher than in the thymus of control subjects. LDH isoenzyme profiles of thymus tumours were similar to those described in other neoplasms, except that thymomas with apparent predominance of epithelial cells and with minimal lymphocytic reaction exhibited a marked elevation only in LDH2 relative activity, presumably associated with the specific (secretory) function of epithelial cells. The elevation of H-subunit content, a parameter characteristic of both thymic components (lymphoid and epithelial), correlated closely with a poor clinical condition in patients several years after surgery.

Adolescent↗
PubMed1983

Effect of indomethacin on the blood flow of the rabbit submandibular gland.

Effects of the stimulation of the chorda tympani and acetylcholine infused into the artery of the gland were studied on the blood flow and saliva secretion of the rabbit submandibular gland before and after indomethacin treatment. The enhancement of blood flow and saliva secretion was less apparent after indomethacin than before. Results suggest that endogenous prostaglandins are also involved in the mechanism of the augmentation of blood flow and saliva secretion produced by the stimulation of the chorda tympani in the rabbit submandibular gland.

Acetylcholine↗
PubMed1979

Evaluation of 133Xe clearance curves in the study of lingual blood flow in dogs.

Lingual blood flow was studied in dogs by the 133Xe clearance technique under control conditions, during epinephrine infusion in response to the combined treatment with Regitin and epinephrine. The composite washout curves recorded during control conditions could be resolved into three monoesponential components. It is suggested that the steep initial slope (component I)is caused by the fraction of blood that perfuses the A-V anastomoses of the tongue. Component II and III appear to the effect of epinephrine infusion might indicate the closure of arterio-venous anastomoses containing alpha receptors. Regitin pretreatment could prevent the closure of the arterio-venous anastomoses elicited by epinephrine infusion. The beta receptor stimulating activity of epinephrine migh account for the augmentation of blood flow to lingual musculature.

Animals↗
PubMed1979

Intrarenal distribution of renal blood flow in the rat.

Intrarenal blood flow distribution was studied with the simultaneous use of the 99Tc labelled frog erythrocyte (microsphere) and the radioactive 86Rb fractionation method in the rat. The amount of blood entering the outer cortex (99Tc labelled erythrocytes method) proved to be higher than one perfusing the outer cortex (86Rb method), whereas the amount of blood entering the inner cortex (99Tc method) was less than the amount perfusing the inner cortex and medulla (86Rb method). Hence a group of the preglomerular arterioles in the outer cortex contributes to the blood supply of the inner cortex, on the other hand a group of preglomerular arteries in the inner cortex participates in the postglomerular blood supply of the medulla. Changes in the renal circulation are, however, associated with altered distribution of postglomerular vascular segments supplied by some groups of preglomerular arterioles. From this it is concluded that the postglomerular vessels of the deeper cortical layers constitute a system which is not parallelly coupled but comprises both series- and parallel-coupled sections. The contribution of these sections appears to vary depending on the actual haemodynamic conditions.

Animals↗
PubMed1979

Effect of renal vasodilatation on intrarenal blood flow distribution.

Total renal blood flow (TRBF) and its intrarenal and intracortical distribution were measured before and during renal vasodilatation induced by acetylcholine infusion using the 133Xe washout, 86Rb uptake and radioactive microspheres distribution techniques. A good agreement was observed between TRBF calculated from 133Xe washout and measured with the electromagnetic flowmeter (FM). 86Rb-TRBF was lower than FM-TRBF and, due to the progressive reduction of renal 86Rb uptake, the difference increased with the increase of flow. With the alteration of TRBF the intrarenal distribution of 86Rb uptake did, however, not change significantly and, accordingly there was no redistribution of RBF either between the cortex and medulla, or among the individual cortical zones. The intracortical distribution of labelled microspheres showed, however, moderate flow dependent changes: with the rise of TRBF, due probably to the reduction of the steric hindrance, the estimated fractional perfusion of the inner cortical zones increased. The sum of the per cent 86Rb content of the innermost cortical zone (C4) and of the medulla exceeded the per cent microsphere content of zone C4. It is concluded that the medulla is perfused not exclusively with blood flowing from the juxtamedullar glomeruli. The regional flow values obtained from the 133Xe curves are not comparable with the results obtained by other methods and cannot be attributed to well defined areas of the kidney.

Acetylcholine↗
PubMed1979

Hypertrophic response of the kidney in indomethacin treated rats.

Indomethacin, a potent inhibitor of prostaglandin (PG) synthesis administered to rats in a total dose of 2 x 4.5 mg/kg i.v. for 2 days enhanced compensatory renal hypertrophy following unilateral nephrectomy (UN). The same drug given to rats with intact kidneys in a total dose of 4 x 4.5 mg/kg i.p. in 2 days increased kidney weight renal RNA content and decreased renal acidic ribonuclease activity. It remains to be elucidated whether the suppression of PG synthesis and/or other pharmacological effects of indomethacin account for these findings.

Animals↗