Urotensin II receptor and acetylcholine release from mouse cervical spinal cord nerve terminals.

Accumulating evidence indicate that the neuropeptide urotensin II and urotensin II receptors are expressed in subsets of mammal spinal motoneurons. In fact, a role for the peptide in the regulation of motoneuron function at neuromuscular junction has been suggested, while roles for urotensin II at central synapses in spinal cord have never been addressed. We found that urotensin II receptors were closely associated with cholinergic terminals apposed to a subset of motoneuron and non-motoneuron cell bodies in the ventral horn of the adult mouse cervical spinal cord; urotensin II receptor was also expressed on non-cholinergic nerve terminals. In particular, urotensin II receptor appeared associated with both large cholinergic C-boutons and standard cholinergic terminals contacting some motoneuron perikarya. Cholinergic nerve terminals from mouse cervical spinal cord were equipped with functional presynaptic urotensin II receptors linked to excitation of acetylcholine release. In fact, functional experiments conducted on cervical spinal synaptosomes demonstrated a urotensin II evoked calcium-dependent increase in [(3)H]acetylcholine release pharmacologically verified as consistent with activation of urotensin II receptors. In spinal cord these actions would facilitate cholinergic transmission. These data indicate that, in addition to its role at the neuromuscular junction, urotensin II may control motor function through the modulation of motoneuron activity within the spinal cord.

Distribution pattern of tyrosine hydroxylase in the brain and pituitary of the lungfish Protopterus annectens.

The distribution of tyrosine hydroxylase (TH) was investigated in the brain and pituitary of the African lungfish Protopterus annectens by using immunohistochemistry. TH was expressed in the olfactory bulbs, pallium and subpallium, hypothalamus, tegmentum, reticular formation, nucleus of the solitary tract, and pituitary. In some cells of the hypothalamus and pituitary, TH is colocalized with vasoactive intestinal peptide. In the intermediate and neuronal lobes of the pituitary, TH is expressed in glial fibrillary acidic protein-contained cells. These data suggest that, in lungfish, catecholamine may play a role in olfaction information processing, regulation of visceral activities, and pituitary secretion.

Jun localization in cytosolic and nuclear compartments in brain-pituitary system of the frog, Rana esculenta: an analysis carried out in parallel with GnRH molecular forms during the annual reproductive cycle.

The presence of c-jun like mRNA was assessed in the brain of the frog, Rana esculenta, during the annual sexual cycle. In parallel, Jun protein and GnRH molecular form (mammalian and chicken II also indicated as GnRH1 and GnRH2, respectively) activity was studied in order to establish possible relationships. Northern blot analysis of total RNA reveals the presence of a 2.7 kb c-jun-like mRNA. Western blots, carried out on cytoplasmic and nuclear protein extracts, show the presence of Jun immunoreactive band of 39 kDa in brain and pituitary. Fluctuations of c-jun-like mRNA and Jun immunoreactive protein (cytoplasmic and nuclear) levels in brains during the year indicate relationships among transcription, translation, and nuclear activity. In particular, mRNA levels increase gradually from September until November when Jun protein concentration peaks in cytosolic extracts. Conversely, the nuclear protein reaches highest concentration in July when the cytosolic level shows low values. Immunocytochemical studies confirm the presence of Jun immunoreactivity in both cytoplasmic and nuclear compartments of several brain areas, including those primarily involved in gonadotropin discharge (e.g., anterior preoptic area and preoptic nucleus). GnRH molecular forms and Jun are colocalized in anterior preoptic area and preoptic nucleus. Moreover, during the period characterized by GnRH release, Jun levels strongly decrease in nuclei. Finally, we show that treatments with a GnRH analog (buserelin, Hoechst, Frankfurt) increase Jun levels in brain nuclear extracts.

Microgravity-induced apoptosis in cultured glial cells.

Apoptosis is a form of naturally occurring cell death that plays fundamental roles during embryonic developement. In adults, it neatly disposes of cells damaged by injuries provoked by external causes such as UV radiation, ionisation and heat shock. Alteration of the gravity vector may be one of the external apoptosis inducers. Neurophysiological impairment signs were seen during space flights in astronauts, but very few studies were carried out on the nervous system and none at the cellular level. In this study, we submitted cultured C6 glioma cells to microgravity (0xg) of varying duration, obtained by clinorotation in a Fokker three-dimensional clinostat for 15 min, 30 min, 1h, 20h or 32h. After 30 min at 0xg, numerous nuclei underwent the classical morphological alterations (chromatin condensation, nuclear fragmentation, apoptotic bodies) that lead to the programmed cell death. After 30 min at 0xg, immunostaining for the enzyme caspase-7 was present in the cytoplasm of many cells concurrently with DNA fragmentation identified by the TUNEL method. At 32h, the number of apoptotic nuclei was much reduced indicating the ability of glial cells to adapt to altered gravity.

Oxatomide reduces inflammatory events induced by allergen-specific conjunctival challenge.

BACKGROUND: Allergen-specific conjunctival challenge is a safe and reproducible experimental model to evaluate effectiveness and possible mechanism(s) of action of drugs employed in the treatment of allergic diseases. OBJECTIVE: The protective effect of oxatomide on inflammatory changes that follow allergen-specific conjunctival challenge was assessed in 20 patients with rhinoconjunctivitis due to Parietaria judaica in a double-blind study. METHODS: After a screening allergen-specific conjunctival challenge, patients were randomized into two treatment groups, each being given oxatomide (oral tablets) at 60 mg daily or matching placebo for seven days during off-pollen season. Clinical evaluation, cytologic assessment (number of inflammatory cells and ICAM-1 expression on epithelial cells) were assessed at baseline, 30 minutes, 6 hours, and 24 hours after allergen-specific conjunctival challenge, before and after treatment. In addition, electrocardiograms were obtained before and after treatment. RESULTS: Early phase reaction clinical events as well as total numbers of inflammatory cells were significantly reduced by oxatomide compared with placebo. Late phase reaction clinical events as well as total numbers of inflammatory cells were significantly reduced by oxatomide compared with placebo. ICAM-1 expression was significantly reduced by oxatomide in early phase reactions and late phase reactions compared with placebo. No pathologic cardiac events were detected in any subject. CONCLUSIONS: Oxatomide has a protective effect on clinical and cellular early phase reactions and late phase reactions (including ICAM-1 expression on epithelium) induced by allergen-specific conjunctival challenge and is safe and well tolerated.

[A comparison between amlodipine and nifedipine retard in patients with essential arterial hypertension]. / Confronto tra amlodipina e nifedipina ritardo in pazienti con ipertensione arteriosa essenziale.

Amlodipine, a novel dihydropyridine calcium-antagonist, was compared to slow-release nifedipine in a short-term study on 40 patients with mild to moderate essential hypertension, in order to assess the efficacy and tolerability of two different dihydropyridine calcium-antagonists with short and long half-life. After a two-week single-blind placebo period, patients were given, in a randomized sequence, amlodipine (5 or 10 mg/day od, 20 patients) or nifedipine s.r. (20 or 40 mg BID, 20 patients). At the end of treatment (12 weeks) a significant lowering of arterial pressure was obtained after 24h from the administration of amlodipin (-34/-17 mmHg) and after 12h from the administration of nifedipine s.r. (-33/-16 mmHg). Furthermore, with both drugs, no significant changes in heart rate and ECG have been reported. Amlodipine was better tolerated than nifedipine, as shown by the lower incidence of side effects. Therefore amlodipine proved to be an effective and well tolerated drug in the therapy of mild to moderate hypertension.

Open comparative study to assess the efficacy and safety of two calcium antagonists, amlodipine and diltiazem, in the treatment of symptomatic myocardial ischaemia.

Patients with symptomatic myocardial ischaemia received amlodipine (once daily) or diltiazem (three times daily) for 10 weeks. Amlodipine and diltiazem showed comparable efficacy in reducing angina attack rates and glyceryl trinitrate consumption. Amlodipine produced a significantly greater reduction in the mean rate pressure product. Both drugs were well tolerated with only mild side effects occurring at the higher doses. In two cases, side effects were also reported at the lower dose of diltiazem (30 mg three times daily); none occurred with the 5-mg daily dose of amlodipine. In the overall clinical assessment, efficacy of amlodipine was considered excellent in 100% of cases as compared with 40% for diltiazem. Amlodipine is clearly effective when administered once daily for the treatment of myocardial ischaemia.

[Short and medium term evaluation of captopril-ketanserin combination in mild to moderate arterial hypertension]. / Valutazione a corto-medio termine dell'associazione captopril-ketanserina nell'ipertensione arteriosa lieve-moderata.

Forty patients with mild-to-moderate arterial hypertension were randomized for double-blind treatment with ketanserin (20 mg b.i.d.) vs. captopril (25 mg b.i.d.) for fifteen days. Diastolic pressure was normalized (less than 90 mmHg) in 11 out of 20 patients of both groups. Of the 18 patients not responding to monotherapy, 17 were treated for 45 days with a combination of both drugs at the same dosages. Diastolic blood pressure was normalized in 15 out of these 17, and in one patient it was reduced by more than 10%. Thus the success rate of therapy was 94%.

[Morphologic and functional evaluation of the left ventricle in patients with acromegaly. An echocardiographic study]. / Valutazione morfologica e funzionale del ventricolo sinistro in pazienti con acromegalia. Studio ecocardiografico.

The aim of our study is to detect morphological and functional aspects of left ventricle with noninvasive M-B-Mode echocardiography in acromegalic patients (pz) with and without high blood pressure. We studied 19 acromegalic pz (group A) and 19 normal pz (group N). All subjects were evaluated for the following parameters: left ventricular mass index (MI); end diastolic volume index (EDVI); end systolic volume index (ESVI); ejection fraction (EF); end systolic stress (ESS). Group A vs group N shows an increase of cardiac mass (p less than 0.01), of EDVI (p less than 0.05) and of ESS (p less than 0.05). We found the asymmetrical septal hypertrophy, considered from other Authors one of the more evident markers of acromegaly, in only one patient. In conclusion, the acromegalic pz show an increase of cardiac mass and preload and a reduced capacity of adaptation to afterload variation independently of blood pressure values and of the duration of disease, even if they have normal indexes of global systolic function.

Long-term treatment of congestive heart failure with oral ibopamine. Effects of rhythm disorders and neurohormonal alterations.

A group of 30 patients with II-III NYHA class cardiac insufficiency was treated with ibopamine in association with other drugs for a 6-month period. The patients were submitted to a 24-h ambulatory ECG Holter monitoring, chest X-ray, Doppler echocardiography in order to calculate total peripheral vascular resistance. Blood levels of aldosterone and renin-angiotensin activity in plasma were also measured, together with norepinephrine excretion. The measurements and recordings were performed in basal conditions before the trial, and were repeated after the first, second, third and sixth month. Laboratory tests were performed at the baseline and after 6 months. The results showed a significant decline in the number of ventricular and supraventricular ectopic beats after treatment. Heart rate did not change. Cardio-thoracic ratio decreased significantly along with peripheral vascular resistance. A very noticeable decline in all three neurohormonal parameters, i.e. norepinephrine excretion, blood level of aldosterone and renin activity in plasma was observed after 1 month's treatment, and this reduction was still present without any attenuation after 6 months. No significant changes were observed in routine laboratory tests.

Right ventricular dysplasia: radioisotopic angiography.

To evaluate if regional wall motion (RWM) abnormalities detected at rest in patients with high presumption of right ventricular dysplasia (RVD) are confirmed by stress test and could be considered of diagnostic value in the clinical setting of the disease, 12 patients underwent first-pass radionuclide angiography (RA) at rest and during exercise. The mean global right ventricular ejection fraction (EF) was 29.83 +/- 7.91 at rest; during exercise, we found a non-significant increase (32.16 +/- 9.8, P greater than 0.05). Six segments with systo-diastolic dyskinesis, three segments with diastolic dyskinesis, and 10 segments with akinesis at rest confirmed the same degrees of dysfunction during exercise. Eight of the 15 hypokinetic segments at rest showed normal function during exercise; the remaining seven confirmed the same degree of dysfunction during exercise. We conclude that various degrees of RWM abnormalities are found in all patients with RVD; hypokinetic dysfunction has to be confirmed by exercise. RWM abnormalities are not specific for RVD, and clinical and electrophysiological data should be combined to obtain as much evidence as possible for diagnosis.

[The echocardiographic examination associated with the cold pressor test or the isometric force test in the evaluation of ischemic heart disease]. / L'esame ecocardiografico associato a cold pressor test o a sforzo isometrico nella valutazione della cardiopatia ischemica.

Sixteen angina patients were submitted to echocardiographic examination during the cold pressor test and during hand grip. Certain left ventricular function echocardiographic parameters were assessed in these subjects and in a further 14 patients presenting negative histories for cardiovascular diseases who represented the control group. Of the two tests associated with echocardiography, the cold pressor test appeared capable of inducing the more evident changes on left ventricular function compared to isometric effort in subjects suffering from ischaemic cardiopathy.

Absence of proarrhythmic effects of ibopamine in patients with congestive heart failure.

Ibopamine, the di-isobutyric ester of N-methyldopamine, is an orally effective dopamine-related drug. Ibopamine acts mainly through the stimulation of beta 1- and beta 2-adrenergic and dopaminic DA1 and DA2 receptors. Cardiac beta 1 activation may facilitate the occurrence of arrhythmias, by reducing the mean refractory period. The aim of this multicenter investigation was to ascertain whether the administration of ibopamine can induce any rhythm disorder or increase pre-existing arrhythmias. In the first part of the investigation, after a washout period 20 patients were treated randomly under double-blind conditions with ibopamine (100 mg t.i.d.) or placebo for 7 days. In the second part of the study, 25 patients were treated with placebo for 7 days, and then with ibopamine (100 mg t.i.d. and 200 mg t.i.d.) for another two 7-day periods. The results did not show any increase in arrhythmias during the two ibopamine periods, in comparison with the data collected under placebo treatment. Ibopamine did not affect heart rate and blood pressure. The number of SVPBs and VPBs decreased considerably in several patients and also the Lown classification improved after ibopamine treatment, even after the 200 mg t.i.d. dose. It can be concluded that ibopamine does not seem to elicit any significant proarrhythmic property.

Thalassemic cardiomyopathy: echocardiographic difference between major and intermediate thalassemia at rest and during isometric effort: yearly follow-up.

Left ventricular (LV) performance was studied in young patients with severe chronic anemia due to beta-thalassemia major, intermedia, and in healthy control subjects. M-mode echocardiograms were recorded in each patient and semiautomatic computerized analysis of the tracings provided data relating to LV performance. Then a statistical analysis of the difference between each specific thalassemic group and the normal subjects was made using Student's t-test for unpaired data. The study showed that cardiac dysfunction is more serious in major than in intermediate beta thalassemia. A follow-up one year later showed a progressive deterioration of the cardiac indices, in spite of treatment with desferrioxamine. A handgrip test was performed in the follow-up study, which permitted us to distinguish different groups relative to the changes in LV performance indices. Our findings indicate that echocardiography provides a simple noninvasive means for assessing changes in the cardiac structure and function, which should also prove useful in the serial evaluation of patients at risk of developing myocardial iron deposition.

[Radioisotope study (first pass) of left ventricular function in 2 oblique projections using gold-195m after myocardial infarction]. / Studio radioisotopico (primo transito) della funzione ventricolare sinistra in due proiezioni oblique con l'uso di oro 195m nell'infarto miocardico pregresso.

The radioisotope 195Aum because of its short halflife of 30 seconds and reduced radiation exposure allows routine first pass examinations in two oblique projections, i.e. right anterior and left anterior oblique. The value of the additional left anterior oblique projection has been examined in 30 patients after previous myocardial infarction by functional imaging in two oblique projections. The multicrystal gamma camera connected with a microprocessor and a contrast injector have been used. For assessment of left ventricular function the following functional images have been adopted: the regional ejection fractions (rEF), the regional ejection rates (rEJR) and the regional mean transit times (rMTT). The right anterior oblique view resulted diagnostic for miocardial infarction in 26 of 30 patients (86,6%). The left anterior oblique view was informative with respect of septal extension 17 times (58,6%), lateral extension 9 times (31%), septal and lateral extension 3 times. With regard of the different functional images the rMTT showed the severe dysfunction in the infarcted zones in all patients (100%), the rEJR in 29 patients (96,6%), the rEF in 28 cases (93,3%). In 4 cases dyskinesia was observed, twice in the left anterior oblique view and also twice in the right anterior oblique view. In patients with previous MI it is necessary to record the second left anterior oblique projection which can be done routinely by the use of 195Aum and first pass technique. On functional images, maximum information is obtained by the rMTT which visualizes the zones of severe dysfunction and its extension.

[Noninvasive first-pass study of the heart with the short-lived radionuclide gold 195m]. / Nichtinvasive First Pass-Untersuchung des Herzens mit dem kurzlebigen Radionuklid Aurum 195m.

The new shortlived radionuclide Aurum 195 m (T1/2: 30.5 sec) has been used for 1,596 first-pass examinations of 792 patients. During first-pass the same maximum count rates of an average of 300,000 cts/sec and after background subtraction the same enddiastolic counts over the left ventricle averaging 10,000 cts/sec can be achieved as with the previously used Tc-99 m pertechnetate injections. The short half-life and fast regeneration of Au-195 m within 3 minutes allow repeated, subsequent injections with significant reduction in radiation exposure. Half of the studies were done at rest and exercise, one third in two oblique projections, RAO and LAO. Examinations in two projections improve the information facilitating the localization of ischemic or infarcted LV-regions particularly with respect of septal and/or lateral extension. Strictly lateral dysfunction may sometimes be only recognizable in the second LAO-projection. The RAO-view best discriminates the extension along the anterior and infero-posterior wall.