Quantitative autoradiography of serotonin uptake sites in rat brain using [H]cyanoimipramine

The binding of [³H]cyanoimipramine to serotonin uptake sites in rat brain slices was studied using quantitative autoradiography. Binding was of high affinity and was to a single class of binding site. This is in contrast to results previously obtained by others with [³H]imipramine where two binding sites were observed. The sites labeled by [³H]cyanoimipramine had properties consistent with this ligand labeling serotonin uptake sites, as: (1) binding is displaced by drugs which are potent inhibitors of serotonin uptake but not by drugs which are weak inhibitors of uptake; (2) binding is dependent on the presence of sodium ions as is the uptake of serotonin; (3) binding is almost completely eliminated in the brains of rats lesioned by the serotonin neurotoxin 5,7-dihydroxytryptamine; (4) the distribution of binding sites throughout the rat brain is highly correlated with that found previously for [³H]indalpine, a potent serotonin uptake inhibitor, and for [³H]imipramine. The properties of binding of [³H]cyanoimipramine make it an ideal ligand for the quantitative autoradiography of serotonin uptake sites.     

Gastrointestinal and in vitro release of copper, cadmium, indium, mercury and zinc from conventional and copper-rich amalgams

Abstract – Particles of a conventional lathe-cut, a spherical non-gamma 2 and a copper amalgam have been gastrointestinally administered to rats for the purpose of evaluation of the dissolution resistance. The animals were sacrificed after 20 hrs. The contents of copper, cadmium, indium, mercury and zinc in kidney, liver, lung or blood were measured using nuclear tracer techniques. From a copper amalgam an extreme release of copper was demonstrated. This study simulates the clinical condition of elemental release from swallowed amalgam particles after amalgam insertion or after removal of old amalgam fillings. Specimens of the same types of amalgams were also exposed to artificial saliva for a period of 10 days. The amounts of copper and mercury released were measured with flame and flameless atomic absorption spectrophotometry respectively. The levels of copper and mercury released from the copper amalgam were approximately 50 times those of the two other amalgam types studied.     

Changes in high affinity choline uptake in rat cortex following lesions of the magnocellular forebrain nuclei

High affinity choline uptake (HACU) and choline acetyltransferase (CAT) were measured in the cerebral cortex of rats 4 and 20 days after placing electrolytic lesions in the magnocellular forebrain nuclei (MFN) or in the pallidum.Four days after MFN lesion a 40–50% decrease in ipsilateral cortical HACU was found and a slightly smaller decrease was found 4 days after the pallidum lesion. Twenty days after the lesion, HACU activity returned to control values in the ipsilateral parietal cortex, its decrease was smaller than 4 days postlesion in the ipsilateral frontal cortex and a significant increase was found in the contralateral cortex.CAT activity showed a 40% decrease in the frontal, parietal and occipital ipsilateral cortex 4 days after MFN lesion. The same decrease was found 20 days postlesion. However, at this time a significant increase in CAT activity was detected in the contralateral cortex.The ipsilateral recovery of HACU activity 20 days after the lesions and the contralateral increase in HACU and CAT activity demonstrate the remarkable and widespread functional adjustment associated with discrete brain lesions. The existence of a large cholinergic pathway projecting to the neocortex from the basal forebrain region is also confirmed.     

Effect of Hypophysectomy and Adrenalectomy on 5-Hydroxytryptamine Uptake by Rat Hypothalamic Synaptosomes and Blood Platelets

Abstract: The effect of adrenalectomy and hypophysectomy on 5-HT uptake by rat platelets and hypothalamic synaptosomes taken from the same animal was studied. The experiments were performed 1–2 weeks after the operations or the shamoperations. After adrenalectomy a significant decrease of 25% in 5-HT uptake by platelets was noted. In synaptosomes there was a similar trend, but the decrease was not significant. After hypophysectomy a significant 25% decrease in 5-HT uptake was observed both in platelets and in synaptosomes. These results suggest that corticosteroid hormones might mediate adaptive changes of 5-HT uptake both in synaptosomes and in blood platelets. Blood platelets have been used as a peripheral model of serotoninergic nerve terminal in studies concerning physiology of monoamines systems, but the present results suggest that also in some pathological conditions changes in platelet biochemistry could reflect those in the CNS neurones.     

Marrow Cell Uptake by Megakaryocytes in Routine Bone Marrow Smears during Blood Loss

In studying smears of marrow aspirates, we have encountered the presence of normal appearing haemopoietic cells within megakaryocytes. We have then searched routine marrow smears from 125 patients seen in our service during 3 years. The presence of marrow cells (granulocytic, erythroid, and lymphoid cells) within megakaryocytes was seen in 16 cases of whom 9 had documented bleeding and 5 had carcinoma. 3 patients were suspected of bleeding but this was not documented. 56 % of patients with bleeding and 83 % of patients with carcinoma seen during this period displayed this phenomenon. A search for this phenomenon in routine marrow smears may reveal unsuspected blood loss.     

间硝苯吡啶与硝苯吡啶对左室功能及心肌氧耗的比较研究

间硝苯吡啶(M-Nif)为新合成的钙拮抗剂。实验表明,M-Nif可增加麻醉狗的CI、SI,降低麻醉猫的舒张压、TTI较Nif强而持久。Nif增加心率,M-Nif却无影响或略减少。M-Nif增加冠状窦氧含量,缩小动静脉氧差的强度弱于Nif,但降低心肌氧摄取率。二氧化碳产生率则较Nif强。提示M-Nif治疗充血性心力衰竭优于Nif。     

The incorporation of triethylcholine into isolated guinea pig cerebral cortex synaptosomal and synaptic vesicle fractions

The incorporation of triethylcholine (TEC) into synaptosomal and synaptic vesicle fractions prepared from guinea pig cerebral cortices was investigated. TEC was tritium labelled by a catalytic exchange process and purified by thin layer chromatography. ³H-TEC was incorporated into isolated synaptosomal fractions in both tris medium and a complete medium containing an external energy source. In this medium about 50% of the ³H-TEC incorporated was taken up into a chloroform-soluble fraction; almost no uptake into chloroform was demonstrated in the complete medium. After incubation of ³H-TEC with isolated synaptosomal fractions the ³H-TEC was shown to be localized in the subsynaptosomal synaptic vesicle fraction. The uptake process for ³H-TEC is inhibited by high concentrations of hemicholinium and choline. The temperature and time studies suggest that in synaptosomes an uptake process for TEC exists similar to that which has been observed for choline.     

Renal vein oxygen saturation in renal artery stenosis

Summary. Renal vein oxygen-saturation was measured in 56 patients with arterial hypertension and unilateral stenosis or occlusion of the renal artery. Oxygen-saturation in blood from the ischaemic kidney (84.4%, range 73–93%) was significantly higher than that from the ‘normal’ contralateral kidney (81.2%, range 70–90%, P<0.001). In only six patients, the ischaemic kidney revealed a venous oxygen-saturation below the contralateral value (mean difference ischaemic-normal kidney 3.2%, range -6 to 15%). The results indicate that the oxygen uptake in the chronic ischaemic kidney is more decreased than its blood flow. This is probably due to decreased filtration fraction and filtered sodium with subsequent reduction in absolute tubular re-absorption of sodium ions.     

A 12-week double-blind multi-centre study of paroxetine and imipramine in hospitalized depressed patients

Fifty-seven inpatients with major depression (DSM-III-R) entered a 12-week study comparing paroxetine and imipramine. Trends (not reaching statistical significance) in favour of paroxetine were seen on the Hamilton Depression Rating Scale (HDRS) and the Montgomery-Åsberg Depression Rating Scale (MADRS). The UKU Side Effect Rating Scale showed a significant difference in favour of paroxetine on reduced salivation. Global evaluation of side effect symptoms showed that significantly more paroxetine patients had no side effects, both in the investigators’ and the patients’ opinion. These results are in line with previous findings of paroxetine being an effective and well tolerated antidepressant.     

Comparison of the subregional distributions of the monoamine vesicular transporter and dopamine uptake complex in the rat striatum and changes during aging

Summary We have studied the heterogeneous distribution of the vesicular monoamine transporter, labelled with³H dihydrotetrabenazine (³H TBZOH) and the dopamine uptake complex, labelled with³H GBR12783 in the rat striatum. The ratio TBZOH/GBR12783 was higher in the anterior part of the striatum than in the caudal part. This discrepancy could not be explained by the contribution of serotoninergic innervation to³H TBZOH binding, since the ratio TBZOH/citalopram was also higher in the anterior striatum than in the caudal striatum. The monoamine vesicular transporter and the dopamine uptake complex were more abundant in the lateral regions than in the regions situated near the midline. In the caudal striatum, the ventral part was richer in vesicular transporter than the dorsal part. In aged rats (30 months), a significant decrease in the density of both transporters was noticed in the middle part of the striatum. In the anterior part of the striatum, the ratio TBZOH/GBR12783 was elevated in aged rats compared to adult ones. This could participate in a functional adaptation of the partially diminished population of dopaminergic neurons during aging.