As a result of controversy in the literature regarding the classification and nomenclature of functional receptors for 5-hydroxytryptamine (5-HT), a framework for classification is proposed. The formulation of these proposals has only been made possible by the recent advent of new drug tools. It is considered that there are three main types of 5-HT… (More)
Two experiments were conducted to investigate the effects of training on a region of the chick brain known to be critically involved in imprinting, the intermediate and medial extent of the hyperstriatum ventrale (IMHV). In the first experiment, three groups of chicks were used: (i) dark-reared (n = 9), (ii) trained for 20 min (n = 17), and (iii) trained… (More)
Fourteen chicks were hatched and reared in darkness to approximately equal to 21 h when they were exposed to overhead illumination for 0.5 h and then to an imprinting stimulus (a pulsing red light) for 20 min. The chicks were then matched in pairs on the basis of their activity. One member of each pair was returned to the dark and the other was trained for… (More)
The intermediate part of the medial component of the hyperstriatum ventrale (IMHV) of the chick telencephalon is implicated in the learning process of imprinting. The afferent connections of this region were investigated using the retrograde neuronal tracers horseradish peroxidase (HRP), nuclear yellow and fast blue. Labelled cells were found (i)… (More)
The distribution of cholinergic receptor binding sites was studied in certain areas of the chick brain, especially that part (IMHV) of hyperstriatum ventrale which has previously been implicated in the imprinting process. There was relatively little binding of [125I]-alpha-bungarotoxin in this region, as shown using an autoradiographic technique. In… (More)
The coordinated iron structure and ferrochelatase binding surface of human frataxin have been characterized to provide insight into the protein's ability to serve as the iron chaperone during heme biosynthesis.
It has been suggested that tryptamine can stimulate specific receptors distinct from those for 5-hydroxytryptamine (5-HT). We have examined this possibility in the rat isolated caudal artery, paying particular attention to the involvement of monoamine oxidase metabolism and alpha-adrenoceptors, two factors that can complicate the quantification of… (More)