Limbic system involvement in the increase in plasma prolactin following cortical spreading depression in gonadotropin-treated female rats.
Cortical spreading depression (SD) was induced by applying 25% KCl to the frontal cerebral cortex in female rats under continuous ether anesthesia. Three weeks previously the animals had been subjected to sham operation, bilateral surgical "deefferentation" of the amygdala or transection of the dorsal columns of the fornix. During the week prior to experiment the rats were made "pseudopregnant" by treatment with PMS and hCG. Plasma prolactin was measured by radioimmunoassay in blood samples obtained from the peripheral circulation at 20 min intervals. After two control samples had been taken, KCl was applied to the cortex and sampling continued for another 100 min; In the sham-operated group prolactin levels increased with time following the application of KCl. Fornix-cut animals showed a similar, although briefer, increase with values significantly lower than those found in sham-operated animals at 80 min. The increase in plasma prolactin observed in sham-operated and fornix groups was completely abolished in amygdala-cut animals. These results indicate that limbic structures play a significant role in the mechanisms by which cortical SD elevates plasma prolactin levels under the present experimental conditions.
D000679:Amygdala / Q000187:drug effects / Q000502:physiology; D000818:Animals; D002540:Cerebral Cortex / Q000502:physiology*; D006063:Chorionic Gonadotropin / Q000494:pharmacology*; D013181:Cortical Spreading Depression / Q000187:drug effects*; D005260:Female; D006064:Gonadotropins, Equine / Q000494:pharmacology*; D008032:Limbic System / Q000187:drug effects / Q000502:physiology*; D011189:Potassium Chloride / Q000494:pharmacology; D011388:Prolactin / Q000097:blood*; D051381:Rats; D013238:Stereotaxic Techniques; D013997:Time Factors
D006063:Chorionic Gonadotropin; D006064:Gonadotropins, Equine; D011189:Potassium Chloride; D011388:Prolactin