title: Strontium supports synaptic transmission and long-lasting potentiation in the hippocampus.
abstract: (1) Synaptic transmission was studied in isolated transverse hippocampal slices from guinea pigs. Extracellular evoked potentials were recorded in the region CA1. (2) Changing the normal perfusion solution (containing 2 mM Ca2+) to calcium-free Ringer abolished synaptic transmission which was again restored by adding strontium. A synaptic efficacy of 25--50% ofn normal was obtained for 10 mM Sr2+. (3) Two different synaptic inputs to CA1 pyramidal cells were tested with respect to their ability to produce long-lasting synaptic potentiation after tetanization in strontium Ringer. Following a brief tetanus the field EPSP and, especially, the population spike were greatly enhanced. (4) The potentiation so produced was similar to the long-lasting potentiation seen in the normal slice, because it (i) had a very long duration (hours), (ii) was specific for the tetanized pathway, (iii) showed potentiation of both 'volley-EPSP' and 'EPSP-spike' relations, and (iv) was accompanied by short-lasting (less than 5 min) generalized depression.
mesh_terms: D000818:Animals; D002118:Calcium / Q000494:pharmacology; D046508:Culture Techniques; D004558:Electric Stimulation; D005071:Evoked Potentials / Q000187:drug effects; D006168:Guinea Pigs; D006624:Hippocampus / Q000187:drug effects*; D013324:Strontium / Q000494:pharmacology*; D013569:Synapses / Q000187:drug effects*; D009435:Synaptic Transmission / Q000187:drug effects*
chemical_list: D002118:Calcium; D013324:Strontium