University Student Progressions and First Year Behaviour

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Age-related changes in the noradrenergic pattern and receptor responses of the rat cardiovascular system after repeated microwave exposure.

In the present research the effect of repeated microwave exposure on the noradrenergic pattern by histofluorescence method and on receptor-mediated responses using alpha and beta agonists in myocardium and aorta of young-adult and aged rats was studied. Young-adult irradiated rats showed an increase in noradrenergic innervation more marked in myocardial tissue, while an increase in maximal response to the agonist was found only at aortic level. Aged stressed rats exhibited an increase in fluorescent fibres at atrial and aortic level, but in the atrial section this increase was found to be less evident than in young-adult animals. Functional data in aged rats revealed a more marked decrease in maximal response ratio (M.R.R.) of myocardial tissue than in young-adult rats, together with a noticeable decrease in maximal response at aortic level. These results indicate no direct correlation between morphological and functional data. Participation of both central and peripheral mechanisms is suggested

Inhibition of experimental angiogenesis by the somatostatin analogue octreotide acetate (SMS 201-995)

The present study investigates the effect of the somatostatin analogue octreotide acetate (SMS 201-995) on experimental angiogenesis in vitro and in vivo. Octreotide reduced the proliferation of human HUV-EC-C endothelial cells (mean, -45.8% versus controls at 10(-9) M; P < 0.05) as well as the density of the vascular network of the chick chorioallantoic membrane (mean, -35.7% versus controls at 50 microgram; P < 0.05). Furthermore, octreotide significantly inhibited chick chorioallantoic membrane neovascularization by the human MCF-10Aint-2 mammary cells secreting the angiogenic protein FGF-3. The proliferation of endothelial and smooth muscle cells from rat aorta explants on fibronectin was reduced by octreotide 10(-8) M (mean, -32.6% versus controls; P < 0.05), and a similar effect was produced on cells sprouting from explants cultured in fibrin (mean, -52.9% versus controls; P < 0.05). Topical administration of octreotide 10 microgram/day for 6 days inhibited rat cornea neovascularization induced by AgNO3/KNO3 (mean, -50.6% versus controls; P < 0.05). Octreotide 40 microgram/day i.p was tested on angiogenesis in rat mesentery obtained by i.p. injections of compound 48/80, a mast cell degranulating agent, or conditioned medium from MCF-10Aint-2 cells and was able to reduce the extent of neovascularization (mean, -45.6 and -64.1%, respectively, versus controls; P < 0.05). These data provide evidence that octreotide is an inhibitor of experimental angiogenesis in vitro and in vivo