ISSN:
1432-1106
Keywords:
Unanesthetized cat
;
Cerebellum
;
Purkyně cells
;
Mossy fiber fields
;
Climbing fiber fields
;
Cutaneous mechanoreceptors
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary 1. In cats with local anaesthesia the cutaneous receptive fields of individual Purkyně cells of the vermis and pars intermedia of the anterior lobe were assessed by recording the simple spike discharges and climbing fiber responses following controlled mechanical stimulation of the foot pads of all four limbs (taps and pressure stimuli) and of the hairy skin (air jets) of the limbs and the body. 2. Exploring the receptive fields with taps and air jets revealed for the mossy fiber transmitted activity that in a population of 93 cells 37 had small receptive fields from the distal areas of one limb only; 28 had discontinuous receptive fields in two limbs and the others had their receptive fields on three or four limbs (multiple discontinuous fields) or over all or almost all of the body surface (widespread fields). 3. Testing with pressure stimuli to the toe pads inside and outside the receptive fields outlined with taps and air jets led to modifications of the simple spike discharges in 86 of 90 cells investigated in this way. Inclusion of these pressure fields increases the percentage of cells with discontinuous multiple mossy fiber transmitted receptive fields on three or four limbs to nearly 70% of our sample of Purkyně cells. 4. Approximately 50% of the cells with mossy fiber transmitted receptive fields also had climbing fiber transmitted fields. With the climbing fiber input the receptive fields were comparable with those for mossy fiber inputs when exploring with taps or air jets. Some additional climbing fiber transmitted cutaneous receptive fields were found with pressure stimuli. These pressure fields were usually restricted to one or two limbs. 5. These findings imply that the mossy fiber transmitted receptive fields of a given Purkyně cell usually extended over a wider area than the climbing fiber transmitted fields. As a rule the (small) climbing fiber fields were overlapped more or less completely by the (large) mossy fiber fields. 6. The receptive fields were either purely excitatory or partly excitatory and partly inhibitory. Pure inhibitory fields were rare. Within a mixed field no dominant pattern has been detected in regard to the arrangement of the excitatory and inhibitory areas. With the multiple fields from three or four limbs, receptive fields of complex composition seem to be the rule rather than the exception. It appears that in samples of cells like the present, each one has its own individuality in regard to shape and extent and in the intermingling of the excitatory and inhibitory field areas from mossy and climbing fiber inputs.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00235507
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