Adenylyl cyclase (AC) in brain cortex from young (12-day-old) rats exhibits markedly higher activity than in adult (90-day-old) animals. In order to find some possibly different regulatory features of AC in these two age groups, here we modulated AC activity by dithiothreitol (DTT), Fe(2+), ascorbic acid and suramin. We did not detect any substantial difference between the effects of all these tested agents on AC activity in cerebrocortical membranes from young and adult rats, and the enzyme activity was always about two-fold higher in the former preparations. Nevertheless, several interesting findings have come out of these investigations. Whereas forskolin- and Mn(2+)-stimulated AC activity was significantly enhanced by the addition of DTT, increased concentrations of Fe(2+) ions or ascorbic acid substantially suppressed the enzyme activity. Lipid peroxidation induced by suitable combinations of DTT/Fe(2+) or by ascorbic acid did not influence AC activity. We have also observed that PKC- or protein tyrosine kinase-mediated phosphorylation apparently does not play any significant role in different activity of AC determined in cerebrocortical preparations from young and adult rats. Our experiments analysing the presumed modulatory role of suramin revealed that this pharmacologically important drug may act as a direct inhibitor of AC. The enzyme activity was diminished to the same extent by suramin in membranes from both tested age groups. Our present data show that AC is regulated similarly in brain cortex from both young and adult rats, but its overall activity is much lower in adulthood.

• MeSH
• adenylátcyklasy chemie   metabolismus   MeSH
• buněčná membrána metabolismus   MeSH
• časové faktory MeSH
• dithiothreitol farmakologie   MeSH
• financování organizované MeSH
• fluoridy farmakologie   MeSH
• fosforylace MeSH
• guanosin 5'-O-(3-thiotrifosfát) metabolismus   MeSH
• inhibitory adenylylcyklasy MeSH
• kolforsin farmakologie   MeSH
• krysa rodu rattus MeSH
• kyselina askorbová farmakologie   chemie   MeSH
• mangan farmakologie   MeSH
• mozek enzymologie   metabolismus   MeSH
• mozková kůra enzymologie   metabolismus   MeSH
• peroxidace lipidů MeSH
• potkani Wistar MeSH
• proteinkinasa C metabolismus   MeSH
• sloučeniny hliníku farmakologie   MeSH
• stárnutí MeSH
• suramin farmakologie   chemie   metabolismus   MeSH
• tyrosinkinasy metabolismus   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• železo chemie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH