The effect of excitatory amino acid receptor agonists on GH secretion was tested in isolated male rat somatotrophs. N-Methyl-D,L-Aspartate (NMDA) had a dose-dependent stimulatory effect on GH secretion in perifused somatotrophs. The effect was observed already during the first minute after exposure to NMDA and was reversible after its omission. The effect of 1 microM NMDA was inhibited by the NMDA receptor antagonists 10 microM AP7 and 5 microM MK801, and by 5 microM dextromethorphan. L-Glutamate, 100 microM, and 100 microM kainic acid also stimulated GH secretion. The stimulatory effect of NMDA on GH release was paralleled by an increase in 45Ca efflux and an increase in somatotroph intracellular calcium concentration. Efflux of 86Rb (tracer for potassium) was not affected by NMDA. It is concluded that excitatory amino acids can stimulate GH secretion in rats through a direct effect on the somatotrophs.
School violence has been a recurring theme in the Swedish media over the last decade. Unfortunately research on this subject has been scarce and the media picture has therefore often been accepted uncritically. This article presents an overview of what is known about school violence in Sweden. Using a contextual approach it is also investigated to what extent individual level characteristics and features of the school context account for the risk of victimization. On the whole it is found that in schools where social capital, e.g. family and community resources, is low, violence tends to be higher, especially among students with low self-esteem and weak school involvement.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.