Dopaminergic mechanisms in thiophene-2-aldoxime tremor

Summary Tremor induced by thiophene-2-aldoxime is enhanced or reduced in intensity and duration by agents which respectively interfere with or promote dopaminergic tone.This project was supported by a grant from the Lebanese National Research Council. We thank the following companies for the indicated drugs: Abbott (pargyline), Specia (chlorpromazine), Squibb (cinanserin).     

Effect of prostaglandin F2α on the secretion of pancreatic juice induced by secretin and by dopamine

Zusammenfassung Die Wirksamkeit von Prostaglandin F₂ (PGF₂) auf die exokrine Pankreassekretion wurde an einem mit Blut perfundiereten Pankreas-Präparat des Hundes untersucht. PGF₂ (100 g) hemmte die durch Sekretin stimuliete, aber nicht die durch Dopamin stimulierte Sekretion.     

Differential effects of prostaglandins and isoproterenol on cAMP content and Na, K pump activity in rat submandibular acini

The beta-adrenergic agonist isoproterenol and prostaglandins E1 and E2 (but not F2 alpha) increased the cAMP content of rat submandibular acini in vitro, but only isoproterenol enhanced ouabain-sensitive 86Rb (K) uptake. These findings suggest that cAMP is not involved in the activation of the Na, K pump in salivary cells.     

Postsynaptic long-term potentiation follows coupling of dendritic glutamate application and synaptic activation

Dendritic depolarization, which seems to be involved in the induction of long-term potentiation (LTP), was elicited by localized glutamate application. When paired to low frequency synaptic activation in the same area, the subsequent changes had features in common with LTP, expressed as an increased probability of firing and shorter spike latency. The EPSP was not significantly increased.     

3-Amino-3-deoxy-D-glucose: an antibiotic produced by a deep-sea bacterium

Gram-positive bacteria isolated from deep-sea sediments of the Pacific basin showed considerable antibacterial activity. A Bacillus strain, isolated from a sediment sample collected at a depth of 4310 m, was shown to produce 3-amino-3-deoxy-D-glucose, a known antibiotic.     

Photoreceptor damage following exposure to excess riboflavin

Flavins generate oxidants during metabolism and when exposed to light. Here we report that the photoreceptor layer of retinas from black-eyed rats is reduced in size by a dietary regime containing excess riboflavin. The effect of excess riboflavin was dose-dependent and was manifested by a decrease in photoreceptor length. This decrease was due in part to a reduction in the thickness of the outer nuclear layer, a structure formed from stacked photoreceptor nuclei. These changes were accompanied by an increase in photoreceptor outer segment autofluorescence following illumination at 328 nm, a wavelength that corresponds to the excitation maxima of oxidized lipopigments of the retinal pigment epithelium.     

Epicatechin can cause the seedling growth inhibitor,nagilactone E,to induce growth stimulation

Summary A possible new role for the flavonoid (–)-epicatechin (II) is described. It has no growth effects on its own, but when it is added to lettuce and rice seeds together with the known seedling growth inhibitor nagilactone E (I), the growth inhibitor activity ofI can cease and growth stimulation can be observed.