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Neurochemical Research

, Volume 18, Issue 5, pp 617–623 | Cite as

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

  • M. D. Lucock
  • M. I. Levene
  • R. Hartley
Original Articles

Abstract

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.

Key Words

5-Methyltetrahydrofolate folate kainic acid nifedipine cerebellum cerebrospinal fluid brain real time monitoring 

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Copyright information

© Plenum Publishing Corporation 1993

Authors and Affiliations

  • M. D. Lucock
    • 1
  • M. I. Levene
    • 1
  • R. Hartley
    • 1
  1. 1.Aeademic Unit of Paediatrics, Department of Clinical Medicine, D Floor, Clarendon Wing, The General Infirmary at LeedsUniversity of LeedsLeedsUK

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