In vitro binding of specific opioid ligands to their respective sites in membrane fractions and the contribution of individual receptor classes (mu, delta, kappa) was studied in rats after longlasting (up to 22 months) section of spinal dorsal roots at the cervical (C5-8) or thoracic (Th1-4) level. This procedure leads to autotomy or scratching of the skin on the operated side. The total number of receptors in the cervical and thoracic spinal cord was more than doubled in both operated and contralateral part of the cord in comparison with intact controls of the same age. In the cervical region, this increase mainly represented a rise in the number of free receptors, whilst in the thoracic region both free and saturated receptors were increased. On the deafferented side, receptor selectivity, especially in the delta and kappa types was decreased.

• MeSH
• denervace MeSH
• diprenorfin metabolismus   MeSH
• krysa rodu Rattus MeSH
• mícha metabolismus   chirurgie   MeSH
• následné studie MeSH
• potkani Wistar MeSH
• receptory opiátové biosyntéza   MeSH
• spinální ganglia fyziologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• diprenorfin MeSH
• receptory opiátové MeSH

• MeSH
• akční potenciály MeSH
• astrocyty fyziologie   MeSH
• demyelinizační nemoci metabolismus   patologie   MeSH
• draslík metabolismus   MeSH
• encefalomyelitida autoimunitní experimentální metabolismus   patologie   MeSH
• experimentální radiační poranění metabolismus   patologie   MeSH
• extracelulární prostor fyziologie   MeSH
• homeostáza * MeSH
• iontové kanály účinky léků   MeSH
• koncentrace vodíkových iontů MeSH
• krysa rodu Rattus MeSH
• mícha cytologie   růst a vývoj   MeSH
• neurony fyziologie   MeSH
• poranění míchy metabolismus   patologie   MeSH
• potkani inbrední LEW MeSH
• zánět MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• draslík MeSH
• iontové kanály MeSH

Activity-related transient changes in extracellular K+ concentration ([K+]c), extracellular pH (pHc), and extracellular volume (EC volume) were studied by means of ion-selective microelectrodes in the adult rat spinal cord in vivo and in neonatal rat spinal cords isolated from pups 3-14 days of age. Repetitive electrical nerve stimulation (10-100 Hz) in adults elicited increases in [K+]c by about 2.0-3.5 mM, followed by a poststimulation K+ undershoot and triphasic alkaline-acid-alkaline changes in pHc. In 3- to 6-day-old pups, the [K+]c increased by as much as 6.5 mM at a stimulation frequency of 10 Hz, and this was accompanied by an alkaline shift. Increases in [K+]c as large as 1.3-2.5 mM accompanied by an alkaline shift were evoked by a single electrical stimulus. Stimulation in 10- to 13-day-old pups produced smaller [K+]c change and an acid shift, which was preceded by a small initial alkaline shift, as in adult rats. We conclude that glial cells buffer the activity-related [K+]c increase and alkaline pHc shifts. Mg2+ blocked the alkaline but not the acid shift. Acetazolamide had no effect on the alkaline shift but blocked the acid shift. The alkaline shift was enhanced and the acid shift blocked by Ba2+, amiloride, 4-acetamido-4'-isothiocyanotostilbene-2,2'-disulfonic acid (SITS), and 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS). Activity-related acid shifts therefore have a complex mechanism, which includes Na+H+ exchange, Cl-/HCO3- exchange, or Na+/Cl-/H+/HCO3- antiport, Na(+)-HCO3- cotransport, and H+ efflux through voltage-sensitive H+ channels.(ABSTRACT TRUNCATED AT 250 WORDS)

• MeSH
• draslík metabolismus   MeSH
• extracelulární prostor metabolismus   MeSH
• koncentrace vodíkových iontů MeSH
• krysa rodu Rattus MeSH
• mícha růst a vývoj   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• draslík MeSH