CHARLES 11. SAWVKR 



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which effectively blocked copulalion-induced ovulation were found, on super- 

 imposing graph-paper reconstructions, to have a common site in the ventro- 

 medial tuberal region (fig. 2A). The hypophyseal portal veins in each of these 

 animals were seen on semi-microdissection to have at least several intact chan- 

 nels. Another interesting common-site lesion, seen in figure 2B, centered in 

 the mammillary bodies and was characterized as blocking mating behavior. 

 These rabbits remained anestrous for months. In the case of four individuals 

 of this group, the anestrous state was maintained in spite of treatment with 



SECTION AA 



Fig. 4. Diagram of sagittal section of rabbit brain (from Am. J. Physiol. 180: 37, 1955). 

 Location of lenticular nucleus indicated in dotted lines. 'Limbic cortex' refers to area from 

 which LC recordings were taken rather than outlining the whole limbic area. Insert shows 

 area from which 'intrinsic olfactory' activit\- was recorded {diagonal lines). Medial forebrain 

 bundle circled in dotted lines. For key abbreviations, see fig. 3. 



extrinsic estrogen. Nevertheless, their ovaries remained in good condition and 

 they were ovulated by triggering the pituitary with intravenous copper acetate 

 (35). Similar behavioral upsets have been reported for the cat (i) and for the 

 guinea pig (8), resulting from lesions at the rostral mesencephalic posterior 

 hypothalamic level. 



An artificial means of triggering the rabbit hypophysis via the nervous system 

 was revealed on injecting histamine into the third ventricle of the brain under 

 weak Nembutal anesthesia (30). This treatment induced ovulation in 8 of 9 

 animals. The changes in electrical activity of the brain under these conditions 



