Modulation of potassium evoked secretory function in rat cerebellar slices measured by real time monitoring: evidence of a possible role for methylfolate in cerebral tissue.
The real time dynamics of K+ evoked neurosecretion in cerebellar slices has been monitored electrochemically. In the presence of 5-methyltetrahydrofolate a statistically significant diminution in secretory response occurs. Agonists to probe the pharmacological basis for this indicate it is not due to voltage sensitive Ca2+ channel blockade, nor does it show any similarity of effect with kainate, whose receptor is a putative binding site for 5-methyltetrahydrofolate. The method is fully validated, although no account is taken of individual molecular species. High performance liquid chromatography combined with off line microbiological assay could only detect 5-methyltetrahydrofolate in cerebrospinal fluid. We therefore discuss our findings in relation to possible cerebral roles for cerebrospinal fluid 5-methyltetrahydrofolate in the context of both membrane and transmitter related interactions.
Lucock
M D
MD
University of Leeds, Department of Clinical Medicine, General Infirmary, UK.
Levene
M I
MI
Hartley
R
R
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002531:Cerebellum / Q000187:drug effects / Q000378:metabolism*; D004533:Egtazic Acid / Q000494:pharmacology; D004563:Electrochemistry; D004594:Electrophysiology; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013763:Tetrahydrofolates / Q000134:cerebrospinal fluid / Q000494:pharmacology / Q000502:physiology*
D013763:Tetrahydrofolates; D004533:Egtazic Acid; D011188:Potassium; D002118:Calcium; C005984:5-methyltetrahydrofolate; D009638:Norepinephrine