Centrální a periferní nervový systém jsou odděleny od krevního řečiště bariérami, které brání volnému přechodu ve vodě rozpustných molekul prostřednictvím těsných spojů, jež propojují endoteliální buňky a epiteliální buňky plexus chorioideus. Tyto bariéry též hrají roli v influxu esenciálních molekul a odstraňování xenobiotik. V posledních letech jsou objasňovány rozdíly a společné rysy jednotlivých bariérových systémů. Jejich poruchy hrají klíčovou roli v celé řadě chorob nervového systému. Článek objasňuje strukturu a funkci bariérových systémů za fyziologických a patologických okolností., Central and peripheral nervous systems are separated from the bloodstream by barrier structures that prevent free migration of water-soluble molecules through the tight junctions of the choroid plexus endothelial and epithelial cells. These barriers also play a role in the influx of essential molecules and elimination of xenobiotics. In recent years, differences and common features of the various barrier systems are being explored. Their disorders play a key role in a number of nervous system diseases. The present paper describes the structure and function of barrier systems under physiological and pathological conditions., and J. Piťha
This experiment tested the effects of an intracerebroventricular injection of prostaglandin E1 on the sympathetic activation and the thermogenic changes in rats with ibotenate lesions of the ventromedial hypothalamus. Under pentobarbital anesthesia, twelve Sprague-Dawley male rats were lesioned bilaterally in the ventromedial hypothalamus with an injection of ibotenic acid (30 nmol into each side). Sham lesions were carried out in other twelve control rats. After 48 h, all animals were anesthetized with ethyl-urethane. The firing rate of the sympathetic nerves innervating the interscapular brown adipose tissue and the colonic and interscapular brown adipose tissue temperatures were monitored before and after an intracerebroventricular injection of prostaglandin E1 (500 ng) or saline. Prostaglandin E1 induced an increase in the firing rate of sympathetic nerves and the colonic and interscapular brown adipose tissue temperatures. These effects were reduced by the ventromedial hypothalamic lesion. Since ibotenic acid destroys cell bodies, the findings indicate that neurons of the ventromedial hypothalamus play a considerable role in the control of sympathetic activation and the thermogenic changes during prostaglandin E1 hyperthermia., M. Monda, A. Sullo, V. De Luca, A. Viggiano., and Obsahuje bibliografii
Two anti-peptide antisera (anti-A and anti-B) raised against Gryllus bimaculatus allatostatin A1 (Grb-AST A1) and B1 (Grb-AST B1), respectively, were applied in the peroxidase-antiperoxidase (PAP) immunohistochemical technique on complete series of sections from the brain, suboesophageal ganglion, corpora cardiaca (CC), and corpora allata (CA) of G. bimaculatus. Both antisera yielded intense staining of numerous cells and nerve fibres. Serial sections, alternately stained with anti-A and anti-B confirmed that the anti-B generally stained more cells and nerves. Extensive immunoreactivity in the retrocerebral complex suggests that the CC and CA may represent a storage and/or release site for both allatostatin types or allatostatin-like molecules produced in the brain., Günther Witek, Peter Verhaert, Matthias W. Lorenz, Klaus H. Hoffmann, and Lit