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Biomedical subjects

D C McIntyre

Publications and source records attributed to D C McIntyre.

At least 73 records · Page 4Linked to original sources
PubMed1979

Effects of focal vs generalized kindled convulsions from anterior neocortex or amygdala on CER acquisition in rats.

Kindling of the anterior neocortex (AC) was shown to produce a brief focal motor seizure, characterized by a clonic-tonic-clonic response of the forelimbs with the animal in a prone posture. These same brief seizures, as previously reported, did not produce retrograde amnesia in a CER paradigm. With repeated evocations, over several days, the AC convulsions exhibited a dramatic increase of the second clonic phase (generalized) and came to appear similar to amygdala kindled convulsions. These generalized AC convulsions, like briefly kindled amygdala convulsions, produced good retrograde amnesia for a CER. With extensive amygdala kindling prior to CER training, a severe CER acquisition deficit was observed. These latter as well as other data suggest that protracted amygdala kindling produces a subsequent reduced ability to acquire fear motivated responses.

Amygdala↗
PubMed1975

Split-brain rat: transfer and interference of kindled amygdala convulsions.

Rats were subjected to varying degrees of commissurotomy, followed by implantation of a bipolar electrode into each amygdala. After the kindling of six convulsions at one electrode (primary site), the procedure was applied to the contralateral amygdala (secondary site). Convulsions were observed to develop more rapidly, independent of the degree or kind of transection. After 6 secondary site convulsions, the primary site was re-tested and convulsion-triggering was blocked, except in animals with transection of the rostral portion of the corpus callosum (CC). Collectively, the data indicate: (i) amygdala kindling develops a lasting trace which operates through the midbrain or brainstem; (ii) kindling from a second site utilizes this trace; (iii) a series of 6 convulsions produces negative after-effect which manifests itself at the convulsion level via the anterior CC; (iv) the anterior CC is important in determining the laterality of the forelimb clonus; and (v) the inter-amygdala propagation of after-discharge is blocked by the combined sectioning of the anterior CC and the anterior commissure.

Amygdala↗