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The physiological age of mother tubers (Solanum tuberosum L. cv. Kennebec) used as a source of material influenced kinetin-induced in vitro tuberisation. Tuberisation significantly increased with physiological age. Kinetin- or ancymidol-induced tuberisation, plantlet and microtuber dry weight decreased with increasing number of subcultures. Single-node segments obtained from tubers stored for more than 9.5 months at 4 °C showed increased kinetin-induced tuberisation rates and earlier tuberisation than those obtained from younger tubers. For any physiological age, material may be safely multiplied using node propagation until the third subculture and bioassayed for tuberisation without variation in the response.

Indomethacin (IM) is a non-steroidal anti-inflammatory drug which inhibits prostaglandin biosynthesis. It is practically insoluble in water and has the capacity to induce gastric injury. Hydroxypropyl-beta-cyclodextrin (HP-beta-CD) is an alkylated derivative of beta-CD with the capacity to form inclusion complexes with suitable molecules. IM is considered to form partial inclusion complexes with HP-beta-CD by enclosure of the p-chlorobenzoic part of the molecule in the cyclodextrin channel, reducing the adverse effects. The aim of this paper is to evaluate the gastric damage induced by the IM inclusion complex prepared by freeze-drying and spray-drying. A total of 135 Wistar rats weighing 224.4 +/- 62.5 g were put into 10 groups. They were allowed free access to water but were maintained fasted for 18 h before the first administration until the end of the experiment. IM acid-form, IM trihydrated-sodium-salt and IM-HP-beta-CD spray and freeze-dried, at normal and toxic doses, were administered through gastric cannula once/day for 3 days. Seventy-two hours after the first administration, the animals were sacrificed and the stomachs collected and prepared for morphological study by using the haematoxylin-eosin technique. Lesion indexes (rated 0/4) were developed and the type of injury was scored according to the severity of damage and the incidence of microscopic evidence of harm. Microscopic assessment demonstrated levels of injury with index one on 10-25%. The type of complexation method had different incidence but the same degree. The results show that IM inclusion complexation protects against gastric injury, reducing the incidence and the maximum degree of severity from 4 to 1, with a better performance of the spray-dried complex.

Background: It has been hypothesized that the response of holo-transcobalamin (holo-TC) to oral vitamin B -12 may be used to assess absorption. To develop a reliable clinical absorption test that uses holo-TC, it is necessary to determine the optimal timeline for vitamin B-12 administration and postdose assessment. Objective: The objective of this study was to assess the magnitude and patterns of change in the postabsorption response of holo-TC to oral vitamin B-12. Design: Adult (18 -49 y) male and female participants (n = 21) with normal vitamin B-12 status were given three 9-μg doses of vitamin B-12 at 6-h intervals beginning early morning (baseline) on day 1. Blood was drawn at 17 timed intervals over the course of 3 d for the analysis of holo-TC and other indicators of vitamin B-12 status. Results: Mean holo-TC increased significantly (P < 0.001) from baseline at 6 h (11%) and 24 h (50%). TC saturation increased significantly (P < 0.001) from baseline at 12.5 h (33%) and 24 h (50%). The mean cobalamin concentration changed significantly (P

Treatment of gastric ulcers with medicinal plants is quite common in traditional medicine worldwide. Cymbopogon citratus (DC) Stapf. leaves infusion has been used in folk medicine of many tropical and subtropical regions to treat gastric disturbances. The aim of this study was to assess the potential gastroprotective activity of an essential oil-free infusion from C. citratus leaves in acute gastric lesions induced by ethanol in rat.The study was performed on adult male Wistar rats (234.0±22.7g) fasted for 24h but with free access to water. The extract was given orally before (prevention) or after (treatment) intragastric administration of absolute ethanol. Effects of dose (28 or 56mg/kg of body weight) and time of contact of the extract with gastric mucosa (1 or 2h) were also assessed. Animals were sacrificed, being the stomachs removed and the lesions were assessed by macroscopic observation and histopathology.C. citratus extract, given orally before or after ethanol, significantly (P0.01) reduced gastric mucosal injury compared with control group (vehicle+ethanol). The effect does not appear to be dose-dependent. Results also suggested that the extract is more effective when the time of contact with gastric mucosa increases.The results of this assay confirm the gastroprotective activity of C. citratus extract on experimental gastric lesions induced by ethanol, contributing for the pharmacological validation of its traditional use.

The gelling agent Phytagel™ was compared with Difco Bacto-agar forin vitro tuberization of six potato cultivars (Jaerla, Blanka, Claustar, Kennebec, Desiree, and Baraka). On a culture medium with 6% sucrose but lacking growth regulators, tuberization was higher when Phytagel™ was used rather than Difco Bacto-agar, regardless of the photoperiodic regime used. Chemical analyses of the gelling agents revealed a higher mineral content and organic impurities in Bacto-agar than in Phytagel™, which is therefore recommended for microtuber production. The same gelling agent should be used in all treatments of microtuberization experiments in order to draw meaningful physiological conclusions.

The main purpose of this study was to characterize the initial neurotransmission cascade elicited by methamphetamine, analysing simultaneously with in vivo microdialysis monoamine, amino acid and neuropeptide release in substantia nigra and neostriatum of the rat. The main effect of a single systemic dose of methamphetamine (15 mg/kg, subcutaneously) was an increase in dopamine levels, both in substantia nigra ( approximately 10-fold) and neostriatum ( approximately 40-fold), accompanied by a significant, but lesser, increase in dynorphin B ( approximately two-fold, in both regions), and a decrease in monoamine metabolites. A similar effect was also observed after local administration of methamphetamine (100 microm) via the microdialysis probes, but restricted to the treated region. In other experiments, rats were repeatedly treated with methamphetamine or saline, with the last dose administered 12 h before microdialysis. Dopamine K+-stimulated release was decreased following repeated methamphetamine administration compared with that following saline, both in the substantia nigra (by approximately 65%) and neostriatum (by approximately 20%). In contrast, the effect of K+-depolarization on glutamate, aspartate and GABA levels was increased following repeated administration of methamphetamine. In conclusion, apart from an impairment of monoamine neurotransmission, repeated methamphetamine produces changes in amino acid homeostasis, probably leading to NMDA-receptor overstimulation.

A medium containing low amounts of nitrogen (19–23 meq.l−1) produced optimum results in micropropagation as revealed by the number of nodes, internode length, chlorophyll content, and leaf area of four potato cvs. belonging each to four different maturity groups. Decreasing amounts of nitrogen also increased chlorophyll content in all four cultivars tested. The NH 4 + concentration did not have an effect on micropropagation for low nitrogen supplies. In all cvs., except Baraka, there was a “carry over” effect of the nitrogen content in the micropropagation medium onto subsequent tuberization, the lower nitrogen (23 meq.l−1) advancing tuber initiation. Microtuberization of cv. Jaerla was earlier in darkness than under short days regardless of the propagation medium used.

Summary A significant increase in the number of tubers was obtained in the presence of either kinetin (11.6·10 -3 mM), paclobutrazol (8.5·10 -3 mM) or acetate (5.4 mM) for in vitro stolons in darkness, and both single-node sections and intact 3-cm long sprouts were produced after long photoperiod (16 h) subculture. Longitudinal growth decreased whenever tuberization was promoted, especially in the presence of paclobutrazol. Calcium chloride (6 mM) slightly induced tuberization in the dark. Putrescine (0.15 mM) favoured vegetative development in all explants.

Recently the existence of a neurotensin striatonigral pathway strongly up-regulated by methamphetamine has been demonstrated. The aim of the present study was to investigate, using immunohistochemistry and radioimmunoassay, the modulation of this pathway by dopamine antagonists. Rats were injected either with methamphetamine alone or together with the dopamine D1 receptor antagonist, SCH 23390 (R(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-be nzapine hydrochloride), or with the dopamine D2 receptor antagonist, sulpiride. Both techniques showed that this neurotensin striatonigral pathway is regulated by dopamine D1 receptors, since SCH 23390 totally prevented the methamphetamine-induced increase in neurotensin-like immunoreactivity, both in the striatum and in the substantia nigra pars reticulata. Conversely, sulpiride was unable to counteract the effect of methamphetamine in these two areas, suggesting that dopamine D2 receptors are not involved in the regulation of this neurotensin pathway. On the other hand, neurotensin-like immunoreactivity was markedly increased in striatal cell bodies and in the globus pallidus after treatment with sulpiride, indicating that this pathway is mainly regulated by dopamine D2 receptors.

The effect of acute subcutaneous administration of methamphetamine on the expression of neurotensin mRNA was investigated in the adult rat striatum. At different time points (2, 6 and 24 h) following drug administration rats were killed, and mRNA levels were quantified both on films and emulsion-dipped tissue sections from two striatal levels. Two hours after methamphetamine injection, a dramatic increase in neurotensin mRNA levels was detected in different areas of the striatum at both rostral and caudal levels. Numerous positive cells were observed in the dorsomedial, dorsolateral and ventrolateral parts of the striatum. This up-regulation reflected an increase both in the number of cells expressing neurotensin mRNA and in the mean mRNA levels. This increase was still present after 6 h and was similar to the 2 h treated group at the rostral level of the striatum, but lower at the caudal one. Twenty-four hours after methamphetamine injection, neurotensin mRNA levels were back to control values, or in some areas even below. A strong increase in neurotensin mRNA-expressing cells was also seen in the olfactory tubercle, and the time-course was similar to the one observed in the striatum. In a second set of experiments, the effect of methamphetamine was evaluated on adjacent striatal sections hybridized with probes directed against neurotensin and substance P mRNAs, respectively. Two hours after drug administration, a significant increase in the levels of both peptide mRNAs was observed (+190% for neurotensin, +80% for substance P). These results demonstrate that methamphetamine is able to induce a dramatic, rapid and transient increase in striatal neurotensin mRNA levels, which may partly account for the elevation in neurotensin peptide levels observed in the striatonigral pathway after methamphetamine. The different anatomical localization of neurotensin mRNA-expressing cells observed after haloperidol and methamphetamine treatments, as well as the fact that the D1 receptor antagonist SCH-23390 is able to counteract the effect of methamphetamine but not that of haloperidol on neurotensin mRNA expression, suggests that there are at least two different subpopulations of neurotensin cells in the striatum. One population is regulated via D1 receptors and projects to the substantia nigra pars reticulata. The second is sensitive to D2 receptor stimulation and may project to the globus pallidus and/or may represent interneurons.

As recently described, adherence to the Mediterranean diet is associated with improved asthma control. However, evidence of how specific nutrients such as fatty acids and antioxidants may affect this relationship remains largely unknown. We aimed to examine the association between dietary intake of fatty acids and antioxidants and asthma control. A cross-sectional study was developed in 174 asthmatics, mean age of 40 (sd 15) years. Dietary intake was obtained by a FFQ, and nutritional content was calculated using Food Processor Plus™ software (ESHA Research, Inc., Salem, OR, USA). Good asthma control was defined by the combination of forced expiratory volume during the first second, exhaled NO (eNO) and Asthma Control Questionnaire (ACQ) score (control: forced expiratory volume in the first second ≥ 80 %; eNO ≤ 35 ppb; ACQ n-6:n-3 PUFA ratio predicted high eNO, whereas high intakes of n-3 PUFA, α-linolenic acid (ALA) and SFA were associated with low eNO. Odds for controlled asthma improved along with an increased intake of n-3 PUFA (OR 0·14, 95 % CI 0·04, 0·45; P for trend = 0·001), SFA (OR 0·36, 95 % CI 0·13, 0·97; P for trend = 0·047) and ALA (OR 0·18, 95 % CI 0·06, 0·58; P for trend = 0·005). A high n-6:n-3 PUFA ratio increased the odds for uncontrolled asthma (OR 3·69, 95 % CI 1·37, 9·94; P for trend = 0·009), after adjusting for energy intake, sex, age, education and use of inhaled corticosteroids. Higher intakes of n-3 PUFA, ALA and SFA were associated with good asthma control, while the risk for uncontrolled asthma increased with a higher n-6:n-3 PUFA ratio. The present results introduce a protective effect of ALA in asthma control, independent of marine n-3 fatty acids, and provide a rationale to dietary intervention studies in asthma.

Are short-day (SD) conditions inductive or permissive for potato tuberization? This question was addressed using anin vitro culture system. Kinetin induction ofin vitro tuberization in potato stolons cultured in the dark can be partially inhibited by light treatments. Photoperiod required for a major inhibition varied with cultivars: 8 hours for cv. Red Pontiac and 16 hours for cv. Kennebec. Short photoperiods decreased kinetininduced tuberization for all cultivars. Stolons cultured on kinetin-free medium generally did not tuberize, regardless of light treatment. Effects of kinetin and photoperiod on stolon and tuber development are observed. Relationships among kinetin, photoperiod and tuber-inducing stimulus produced under short days are discussed.

Amyloplast division was studied in an in vitro potato (Solanum tuberosum L. cv. Kennebec) stolon tuberizing system which was triggered by the presence of added kinetin. Amyloplast division proceeded by binayr fission of dumbbell shaped amyloplasts. A visible tubular coiled structure from the amylobody appeared to be associated with amyloplast division. Possible ways of daughter amyloplast separation are discussed.

γ-Butyrolactone is a drag known to inhibit the flow of electrical impulses in dopaminergic neurones and to prevent dopamine release in the striatum. In this study, we investigated the effects of this compound on the retrograde transport of neurotensin in the nigrostriatal dopanunergic pathway. The amount of radioactivity measured in the substantia nigra after injection of iodinated neurotensin into the striatum and the time course of its accumulation were not found to be modified in γ-butyrolactone-treated rats. We therefore conclude that the retrograde axonal transport of neurotensin in the nigrostriatal pathu-γ is not affected by reduced dopaminergic firing or by inhibition of the striatal release of dopamine.

Although the existence of receptor transport has been clearly demonstrated in peripheral nerves, there is no clear cut evidence in the brain of such a process for neuropeptide receptors. Because of the localization of neurotensin receptors on dopaminergic terminals, the dopaminergic nigrostriatal pathway appears to be the system of choice for studying the axonal transport of neuropeptide receptors in the brain. When labelled neurotensin was injected into the rat striatum, a delayed accumulation of radioactivity in the ipsilateral substantia nigra was observed about 2 h after injection. An essential requirement to clearly observe this phenomenon was the pretreatment of animals with kelatorphan in order to prevent the labelled neurotensin degradation. The appearance of this labelling was prevented by injection of an excess of unlabelled neurotensin or of neurotensin 8-13, an active neurotensin fragment, but not by neurotensin 1-8, which had no affinity for neurotensin receptors. This process was saturable, microtubule-dependent and occurred only in mesostriatal and nigrostriatal dopaminergic neurons as identified after 6-hydroxydopamine lesion and by autoradiography. These results demonstrate that neurotensin was retrogradely transported by a process involving neurotensin receptors. The retrograde transport of receptor-bound neuropeptide may represent an important dynamic process which conveys information molecules from the synapse towards the cell body.

Removal of the N-terminal methionine of a protein could be critical for its function and stability. Post-translational modifications of recombinant proteins expressed in heterologous systems may change amino-terminal regions. We studied the expression of mature proteins lacking methionine as the N-terminal amino acid in tobacco chloroplasts, using human serum albumin (HSA) as an example. Two approaches were explored. First, we fused the Rubisco small subunit transit peptide to HSA. This chimeric protein was correctly processed in the stroma of the chloroplast and rendered the mature HSA. The second approach took advantage of the endogenous N-terminal methionine cleavage by methionine aminopeptidase. Study of this protein processing reveals a systematic cleavage rule depending on the size of the second amino acid. Analysis of several foreign proteins expressed in tobacco chloroplasts showed a cleavage pattern in accordance to that of endogenous proteins. This knowledge should be taken into account when recombinant proteins with N-terminus relevant for its function are expressed in plastids.

Background: A common genetic polymorphism [transcobalamin (TC) 776C→G] may affect the function of transcobalamin, the protein required for vitamin B-12 cellular uptake and metabolism. Remethylation of homocysteine is dependent on the production of 5-methyltetrahydrofolate and adequate vitamin B-12 for the methionine synthase reaction. Objectives: The objectives were to assess the influence of the TC 776C→G polymorphism on concentrations of the transcobalamin-vitamin B-12 complex (holo-TC) and to determine the combined effects of the TC 776C→G and methylenetetrahydrofolate reductase (MTHFR) 677C→T polymorphisms and vitamin B-12 status on homocysteine concentrations. Design: Healthy, nonpregnant women (n = 359; aged 20-30 y) were screened to determine plasma vitamin B-12, serum holo-TC, and plasma homocysteine concentrations and TC 776C→G and MTHFR 677C→T genotypes. Results: The serum holo-TC concentration for women with the variant TC 776 GG genotype was significantly different (P = 0.0213) from that for subjects with the CC genotype (74 ± 37 and 87 ± 33 pmol/L, respectively). An inverse relation was observed between plasma homocysteine concentrations and both serum holo-TC (P ≤ 0.0001) and plasma vitamin B-12 (P ≤ 0.0001) concentrations, regardless of genotype. Conclusions: These data suggest that the TC 776C→G polymorphism negatively affects the serum holo-TC concentration and provide additional evidence that vitamin B-12 status modulates the homocysteine concentration in this population.

Methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) are important for homocysteine remethylation. This study was designed to determine the influence of genetic variants (MTHFR 677C--T, MTHFR 1298A--C, and MTRR 66A--G), folate, and vitamin B-12 status on plasma homocysteine in women (20-30 y; n = 362). Plasma homocysteine was inversely (P0.0001) associated with serum folate and plasma vitamin B-12 regardless of genotype. Plasma homocysteine was higher (P0.05) for women with the MTHFR 677 TT/1298 AA genotype combination compared with the CC/AA, CC/AC, and CT/AA genotypes. Women with the MTHFR 677 TT/MTRR 66 AG genotype had higher (P0.05) plasma homocysteine than all other genotype combinations except the TT/AA and TT/GG genotypes. There were 5.4-, 4.3-, and 3.8-fold increases (P0.001) in risk for plasma homocysteine in the top 5, 10, and 20%, respectively, of the homocysteine distribution for subjects with the MTHFR 677 TT compared with the CC and CT genotypes. Predicted plasma homocysteine was inversely associated with serum folate (P = 0.003) and plasma vitamin B-12 (P = 0.002), with the degree of correlation dependent on MTHFR 677C--T genotype. These data suggest that coexistence of the MTHFR 677 TT genotype with the MTRR 66A--G polymorphism may exacerbate the effect of the MTHFR variant alone. The potential negative effect of combined polymorphisms of the MTHFR and MTRR genes on plasma homocysteine in at-risk population groups with low folate and/or vitamin B-12 status, such as women of reproductive potential, deserves further investigation.

The carbonated soft drinks intake has changed the children eating habits. This factor may be directly associated with arterial hypertension due the high consumption of sodium present in foods and drinks industrialized. This study was to compare sodium levels between two different types of carbonated soft drinks, carbonated sugar drinks and diet drinks to define what type of drink has the lowest sodium content and alerting healthcare professionals about the presence of sodium in industrialized beverages. The study included labels of carbonated soft drinks n = 33 – sugar drinks (n = 21) or diet drinks (n = 12) – of five different flavors.All carbonated soft drinks evaluated have sodium in its composition. However, the sodium presence in carbonated sugar drinks was significantly lower when compared with carbonated diet drinks (69.05 ± 16.55 vs. 145.30 ± 47.36mg Na/l, respectively).Studies to identify children's eating habits related with increased consumption of foods and drinks manufactured are needed to identify, reduce and prevent high blood pressure. O aumento do consumo dos refrigerantes tem vindo a mudar os hábitos alimentares das crianças brasileiras. Este fator pode ser diretamente associado à hipertensão arterial (HA) devido ao consumo elevado de sódio presente em alimentos e bebidas industrializadas. Comparar os níveis de sódio, descrito nos rótulos dos refrigerantes, para definir que tipo de bebida tem o menor teor de sódio em sua composição e alertar os profissionais de saúde sobre a presença de sódio nos refrigerantes.O estudo incluiu um total de 33 rótulos de refrigerantes, adoçados com açúcar (n=21) ou adoçados artificialmente (n=12) de 5 diferentes sabores.Todos os rótulos avaliados possuem sódio em sua composição. No entanto, a presença de sódio nas bebidas adoçadas com açúcar foi estatisticamente menor quando comparado com as bebidas adoçadas artificialmente (69,05±16,55 vs. 145,30±47,36 mg Na/l). Estudos para identificar os hábitos alimentares das crianças relacionadas com o aumento do consumo de alimentos industrializados são necessários para identificar, reduzir e prevenir a HA Antecedentes: El aumento del consumo de bebidas gaseosas ha ido cambiando los hábitos alimenticios de los niños brasileños. Este factor puede ser directamente asociada con la hipertensión arterial, debido al alto consumo de sodio presente en los alimentos y bebidas industrializados.Objetivo: El presente estudio fue comparar los niveles de sódio, descrito en las etiquetas de las bebidas gaseosas, entre dos tipos diferentes de bebidas gaseosas para definir qué tipo de bebida tiene el más bajo contenido de sodio y alertar a los profesionales de la salud acerca de la presencia de sodio en las bebidas industrializadas.Metodología: El estudio incluyó un total de 33 etiquetas de bebidas gaseosas, endulzado con azúcar (n=21), o endulzado artificialmente (n=12) de los 5 sabores diferentes. Resultados: Todas las etiquetas han evaluado sodio en su composición. Sin embargo, la presencia de sodio en las bebidas endulzadas con azúcar fue menor en comparación con las bebidas endulzadas artificialmente (69.05 ± 16,55 vs 145,30 ± 47,36 mg Na/l). Conclusión: Los estudios para identificar los hábitos alimenticios de los niños en relación con el aumento del consumo de alimentos y bebidas industrializados son necesarios para identificar, reducir y prevenir la hipertensión. Research supported by the FAPEMA/CNPq (PPP – 00969/11) and The Northeast Biotechnology Network (RENORBIO). 3910-3178-31BA | MARIA MARGARIDA COUTINHO DE SEABRA CASTEL-BRANCO CAETANO info:eu-repo/semantics/publishedVersion

It has been reported that methamphetamine (METH) upregulates striatal neurotensin (NT) mRNA levels. The present in situ hybridization study demonstrates, using the dopamine D1 antagonist SCH23390 that this effect is mediated through D1 receptors. Sulpiride, a selective D2 antagonist, induces an upregulation of NT expression, which in some striatal areas is additive to the METH effect. This suggests the existence of at least two NT striatal neuronal populations. One, sensitive to D1 receptors, corresponds to the recently described striatonigral NT pathway. The second one, modulated by D2 receptors, may project to the globus pallidus and/or represent interneurones.

The distribution and origin of neurotensin-like immunoreactivity in the substantia nigra pars reticulata of the rat have been analysed using immunohistochemistry combined with different drug treatments and lesioning techniques. In normal rats, a distinct but weakly fluorescent network of neurotensin-immunoreactive fibers was found in the central part of the substantia nigra pars reticulata. When the animals were treated with reserpine, which suppresses dopamine transmission, a similar pattern of immunoreactivity was found, though the intensity of staining was slightly enhanced. However, when rats were treated with methamphetamine, a potent dopamine releaser, the intensity of immunoreactivity was dramatically increased. In particular, densely packed neurotensin-immunoreactive fibers were found at the dorsal border and at the ventral periphery of the substantia nigra pars reticulata. This pattern of immunoreactivity was found to be similar to that displayed by dynorphin. In the nucleus caudatus, several neurotensin-immunoreactive cell bodies were seen after reserpine treatment. Morphologically similar perikarya were observed in methamphetamine-treated rats, but they were less numerous, whereas no cell bodies were detectable in untreated animals. When a unilateral mechanical transection or an ibotenic acid injection was performed in the striatum, the patterns of neurotensin as well as dynorphin and substance P immunoreactivities in the substantia nigra pars reticulata were strongly affected. Both types of lesion caused a marked, parallel depletion of all three immunoreactive substances on the side ipsilateral to the lesion, where a restricted area was virtually devoid of immunoreactive elements. Thus the present study provides evidence for the existence of a unilateral neurotensin striatonigral pathway, terminating in the pars reticulata. The origin of the neurotensin fibers in the pars compacta has not been established but does not appear to be the caudate nucleus. These results together with evidence from the literature suggest that methamphetamine induced a massive release of dopamine from nigral dendrites acting on presynaptic D1 dopamine receptors located on neurotensinergic terminals leading to a marked increase in neurotensin-like immunoreactivity in the pars reticulata.

The localization of galanin (GAL) and GAL mRNA was studied in rat brain after colchicine or vinblastine treatment using in situ hybridization and immunohistochemistry. GAL-like immunoreactivity was found in glial cells, presumably activated microglia, in the cortex, caudate nucleus and septum, mainly on the injection side. GAL mRNA expression was found in small cells in the same areas with an overlapping distribution, including the adjacent white matter. The results suggest that the glial cells initiate synthesis of the peptide GAL in response to intraventricular injection of high doses of the 2 mitosis inhibitors.

We previously demonstrated the existence of a retrograde axonal transport of radioactivity to the substantia nigra pars compacta following injection of mono-iodinated neurotensin in rat neostriatum. In the present study, the topographical and cellular distribution of this retrogradely transported material was examined by light and electron microscopic autoradiography. Four and a half hours after unilateral injection of [125I]neurotensin in the caudoputamen, retrogradely labelled neuronal cell bodies were detected by light microscopic autoradiography throughout the ipsilateral substantia nigra pars compacta as well as within the ventral tegmental area and retrorubral field. In semithin sections, silver grains were prevalent over the perinuclear cytoplasm of neuronal cell bodies but were also detected over neuronal nuclei. Analysis of electron microscopic autoradiographs revealed that the vast majority (greater than 85%) were associated with neuronal perikarya, unmyelinated and myelinated axons, dendrites and terminals. Within the soma, a significant proportion of silver grains (16% of somatic grains) was detected over the nucleus. However, the majority were identified over the cytoplasm where they often encompassed cytoplasmic organelles, including rough endoplasmic reticulum, mitochondria, Golgi apparatus, lysosomes, and multi-vesicular bodies. In dendrites and axons, a substantial percentage of silver grains (63-89%) was localized over the plasma membrane. A minor proportion (13% of total) of the autoradiographic labelling was detected over myelin sheaths, astrocytes, and oligodendrocytes. The present results are consistent with previous light-microscopic evidence for internalization and retrograde transport of intrastriatal neurotensin within nigrostriatal dopaminergic neurons. They further suggest that retrogradely transported neurotensin may be processed along a variety of intracellular pathways including those mediating degradation in lysosomes and recycling in rough endoplasmic reticulum. The detection of specific autoradiographic labelling in the nucleus supports the concept that neurotensin alone, or complexed to its receptor, might be involved in the regulation of gene expression through direct or indirect interactions with nuclear DNA. Consequently, the retrograde transport of neurotensin in nigrostriatal dopaminergic neurons might provide a vehicle through which events occurring at the level of the axon terminal may initiate long-term biological responses.

In previous studies we have shown that labelled neurotensin injected into the rat striatum was found to be transported retrogradely in dopaminergic neurons through a process which was receptor and microtubule dependent. Now, we show, by in situ hybridization, the consequences of the striatal injection of neurotensin on the gene expression of tyrosine hydroxylase in the substantia nigra. Rats were injected with neurotensin or its fragments in the striatum of one side and with saline or the inactive fragment on the other. The number of nigral cells expressing tyrosine hydroxylase mRNA was found to increase by 40% after injection of neurotensin or its active fragment (neurotensin 8–13). In the same experimental conditions, the inactive fragment (neurotensin 1–8) was without effect. Time-course experiments revealed that the tyrosine hydroxylase mRNA was increased 4 h after neurotensin injection but not at 1 or 16 h. The fact that the increase of mRNA parallels the appearance of labelled neurotensin in the substantia nigra indicates that the changes in the gene expression of tyrosine hydroxylase might be the consequence of the retrograde axonal transport of neurotensin. These results represent the first evidence for the existence of a long-distance retrograde signalling process in which the neuropeptide and presumably its receptor may serve as information molecule between synapses and the cell body.

The aim of the study was to assess the potential in vitro effects of jasmonic acid and kinetin on tuberization of potato (Solanum tuberosum). Of the two, the former was by far the stronger in vitro promoter of stolon tuberization. Number of tubers induced per stolon, tuberization rate, and final tuber weight were higher by factors of 2.8, 2.3, and 6.4, respectively. Bioassay sensitivity of jasmonic acid, measured in terms of the point at which the concentration for inducing tuberization was saturating, was more than 20 times greater than that of kinetin. Tuberization in both cases was associated with a decrease in rooting ability. Jasmonic acid also triggered a general state of induction throughout the stolon.

Two hours after the injection of (3-[125I]iodotyrosyl3) neurotensin into the striatum, a labeling was observed in the ipsilateral substantia nigra. In the present study, we demonstrated by HPLC that this radioactivity corresponded to intact neurotensin and to degradation products of this peptide. This finding provides the first clearcut evidence that a neuropeptide can be internalized and retrogradely transported in brain neurons. Therefore, the fact that intact neurotensin can be seen to exist over a long period of time in the cell body suggests that the retrograde transport process could perhaps be involved in the long-term effects of neuropeptides.

Castel, M NLechardeur, DBlanchard, J CLaduron, P MengIreland1991/03/11Neurosci Lett. 1991 Mar 11;124(1):111-4.; It is now clearly established that fast anterograde axonal transport can be altered during ageing, both in the central and the peripheral nervous systems, but no information is yet available concerning the modifications of fast retrograde axonal transport during senescence. In the present paper, we report the changes occurring in the retrograde axonal transport of neurotensin in dopaminergic neurons of old rats. When iodinated neurotensin was injected into the striatum, a diminution of approximately 50% in the amount of the labelling measured in the ipsilateral substantia nigra was observed in senescent rats by comparison with young adult rats. Nevertheless, the rate of neurotensin transport was not modified. Our results clearly indicate that less neurotensin is transported from the nerve terminals towards the cell bodies in senescent rats which may have possible consequences for dopaminergic neurons.

Peptides of different sizes ranging from a few to more than 40 amino acids are widely and abundantly distributed in the nervous system. In many, if not all cases, these peptides have been demonstrated to occur in neurons which also contain a classic transmitter such as a catecholamine, 5-hydroxytryptamine (5HT), acetylcholine or 7-aminobutyric acid (GABA). As judged from immunohistochemical, and more recently in situ hybridization studies, the levels of peptides and their mRNAs differ markedly between various peptide systems. Moreover, various experimental manipulations have been shown to have a strong and rapid effect on peptide expression. This can be particularly well demonstrated using in situ hybridization. For example, brief electrical, preganglionic stimulation in man dramatically increases levels of mRNA for neuropeptide tyrosine (NPY), as well as for tyrosine hydroxylase and dopamine/,¢-hydroxylase in the postsynaptic sympathetic cell bodies (Schalling et al., 1989). In the present brief article we would like to focus on some of the neuronal systems that produce peptides normally at very low levels or at levels which can not be detected with our histochemical techniques. However, after experimental manipulations such as mechanical damage or drug treatment, there is a marked upregulation to detectable levels, both of peptides and of their mRNAs. Here we will describe four systems, striatal neurons in basal ganglia, hypothalamic neurons in the paraventricular nucleus, chromaffin cells in the adrenal gland and primary sensory neurons.

Ethylene inhibited the tuberization of etiolated potato ( Solanum tuberosum L. var. Red La Soda) sprout sections cultured in vitro . Carbon dioxide did not overcome the C 2 H 4 inhibition but it was required for normal tuberization. Ethylene totally prevented root formation and development. It inhibited stolon elongation, and caused thickening and diageotropical growth of the stolon. In addition, C 2 H 4 prevented the accumulation of both starch and red anthocyanin which are always present in a tuber. Ethylene also inhibited the kinetin-increased tuberization of sprout sections. Three to five days of exposure to CO 2 were required to obtain promotion of tuberization of stolons cultured in vitro . Bicarbonate ion did not affect starch synthetase activity isolated from potato tubers in vitro . The evidence presented suggests that CO 2 gas rather than HCO − 3 or CO 2− 3 ions in equilibrium with dissolved CO 2 was probably responsible for the stimulation. Morphological changes elicited by CO 2 and C 2 H 4 are described and the mechanism of action of both on tuberization is discussed.

Benzyladenine and gibberellic acid sprays (100 mg/l) onEuphorbia lathyris L. plants were absolutely successful (100% of the plants) in inducing a change in its normal decussate phyllotaxis. Benzyladenine produced a change to tetracussate, tricussate and bijugate, and gibberellic acid to spiral phyllotaxis. Benzyladenine and gibberellic acid treatments resulted in a significant increase in apex diameter (72.8% and 19.1% respectively). CCC, Ancymidol, Alar and Glyphosine did not alter decussate phyllotaxis.

Carbon dioxide stimulates tuberization of isolated potato (Solanum tuberosum L.) stolons cultured in vitro. The stimulatory effect is inhibited by C2H4 which is by itself also inhibitory of tuberization. Furthermore, C2H4 inhibits kinetin-induced tuber initiation. Both the formation and elongation of roots are inhibited by C2H4. The antagonistic actions of CO2 and C2H4 on tuberization are discussed.

The electroencephalographic (EEG) effects of the ICV administration of neurotensin (NT 1-13), NT 1-8 (an inactive neurotensin fragment) and D TYR-11 NT (a long-lasting analog of neurotensin) were studied in rats. In awake rats, NT 1-13 (30 micrograms) and D TYR-11 NT (10 micrograms) induced an increase of the power spectrum in the theta range activity (4-7 Hz). In rats recorded during the sleep-wakefulness cycles, NT 1-13 (10 and 30 micrograms) and D TYR-11 NT (10 micrograms) had an awakening effect and also induced an increase of latency to the first episode of the different sleep stages (intermediate stage and slow wave sleep). NT 1-8 (30 and 90 micrograms in awake rats, 10 and 90 micrograms for sleep-wakefulness cycles) was inactive in all these experiments. Thus, it seems that all these effects can be linked to neurotensin receptors; indeed only fragments which recognize receptors possess an EEG activity.