Dopamine-D1 and δ-opioid receptors co-exist in rat striatal neurons

Cocaine’s enhancement of dopaminergic neurotransmission in the mesolimbic pathway plays a critical role in the initial reinforcing properties of this drug. However, other neurotransmitter systems are also integral to the addiction process. A large body of data indicates that opioids and dopamine together mediate emotional and reinforced behaviors. In support of this, cocaine-mediated increases in activation of dopamine D1 receptors (D1R) results in a desensitization of δ-opioid receptor (DOR) signaling through adenylyl cyclase (AC) in striatal neurons. To further define cellular mechanisms underlying this effect, the subcellular distribution of DOR and D1R was examined in the rat dorsolateral striatum. Dual immunoperoxidase/gold-silver detection combined with electron microscopy was used to identify DOR and D1R immunoreactivities in the same section of tissue. Semi-quantitative analysis revealed that a subset of dendritic cellular profiles exhibited both DOR and D1R immunoreactivities. Of 165 randomly sampled D1R immunoreactive profiles, 43% contained DOR. Similarly of 198 DOR-labeled cellular profiles, 52% contained D1R. The present data provide ultrastructural evidence for co-existence between DOR and D1R in striatal neurons, suggesting a possible mechanism whereby D1R modulation may alter DOR function

Development of Sequence Tagged Microsatellite Site (STMS) markers in Azalea

A genomic library was constructed from DNA of two azalea genotypes: a Belgian pot azalea R. simsii hybrid Mevr. Van Belle and a Chinese R. simsii from Daoxian. An enrichment of microsatellite containing sequences was performed as in Van de Wiel et al. (1999). Fragments were sequenced and primers were designed that allow the amplification of the microsatellite repeat. About 220 microsatellite containing clones were selected from the enrichment procedure. Mainly dinucleotide repeats and some trinucleotide repeats were found. The selected primers were tested in a small set of reference varieties to check their value (specificity and polymorphic rate) and to set up the PCR-conditions. Five primer pairs have been tested, two of them gave a specific and polymorphic pattern. They were further screened by radioactive PCR on a selection of 5 plants from the azalea breeders gene pool which included the two genotypes used library construction. These 2 STMS markers uniquely identified the 5 plants

A Glucanase Gene Cosegregates with a QTL for Crown Rust Resistance in \u3cem\u3eL. Perenne\u3c/em\u3e

An important disease in Lolium spp. is crown rust caused by the fungal pathogen Puccinia coronata. In order to study the genetic background of crown rust resistance in L. perenne, a mapping study was carried out and is discussed below. To identify genomic regions or genes involved in resistance, STS markers are extremely useful. This candidate gene approach was applied in the present study

The social learning of threat and safety in the family:Parent-to-child transmission of social fears via verbal information

Parental verbal threat (vs. safety) information regarding the social world may impact a child's fear responses, evident in subjective, behavioral, cognitive, and physiological indices of fear. In this study, primary caregivers provided standardized verbal threat or safety information to their child (N = 68, M = 5.27 years; 34 girls) regarding two strangers in the lab. Following this manipulation, children reported fear beliefs for each stranger. Physiological and behavioral reactions were recorded as children engaged with the two strangers (who were blind to their characterization) in a social interaction task. Child attention to the strangers was measured in a visual search task. Parents also reported their own, and their child's, social anxiety symptoms. Children reported more fear for the stranger paired with threat information, but no significant differences were found in observed child fear, attention, or heart rate. Higher social anxiety symptoms on the side of the parents and the children exacerbated the effect of parental verbal threat on observed fear. Our findings reveal a causal influence of parental verbal threat information only for child‐reported fear and highlight the need to further refine the conditions under which acquired fear beliefs persist and generalize to behavior/physiology or get overruled by nonaversive real‐life encounters

The relation between early behavioural inhibition and later social anxiety, independent of attentional biases to threat

Early behavioural inhibition, a temperamental characteristic defined by fearful, overly-sensitive, avoidant, or withdrawn reactions to the unknown, is a predictor of later social anxiety. However, not all behaviourally inhibited children develop anxiety problems, and attentional bias to threat has been proposed to moderate the relation between behavioural inhibition and anxiety. The current study aimed to further specify the relation between early behavioural inhibition and later social anxiety by testing this potentially moderating role of childhood attentional bias to threat. Behavioural inhibition was assessed during toddlerhood (age 2.5 years) using laboratory observations of children’s behaviours in response to unknown objects and situations. When children were 7.5 years old, attentional bias was measured in 86 children (46 girls) using both a visual probe task and a visual search task with angry and happy faces. Child social anxiety was measured using questionnaires completed by the child and both parents, and clinical interviews conducted with both parents. Our results showed that while early behavioural inhibition was related to later social anxiety, there was no evidence for a moderation of this relation by attentional bias, suggesting that the relation between early fearful temperament and later social anxiety holds across children, independent of their attentional biases.</p