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HANDBOOK OF PHYSIOLOGY -- NEUROPHYSIOLOGY II 



FIG. 5. A, B. Anterior hypothalamic lesions which induced permanent anestrus in the female 

 cat in spite of treatments with exogenous estrogen. C. Ventromedial lesions which induced ovarian 

 atrophy but did not abolish mating behavior if exogenous estrogen was supplied. D. Mammillary 

 lesions with same effect as in C. E. Midsagittal reconstruction showing anterior-posterior extent 

 of lesions A to D. [From Sawyer & Robison, unpublished observations.] 



Interestingly enough the female rabbit does appear 

 to have an hypothalamic mating center (78, 79) in 

 the region proposed by Dempsey and Rioch for the 

 guinea pig and cat. Small bilateral lesions in the mam- 

 millary region induced permanent anestrus which 

 could not be reversed with exogenous estrogen. The 

 ovaries remained in good trophic condition, and they 

 could be ovulated by artificial activation of the 

 hypophysis. On the other hand, rabbits with ventral 

 tuberal lesions involving the arcuate and base of the 

 ventromedial nuclei mated but failed to ovulate. 

 Some of the latter cases revealed ovanan atrophy, 

 and they required exogenous estrogen to stimulate 

 receptivity (fig. 6). These experiments do not exclude 

 the possibility of anterior hypothalamic involvement 



in mating beha\ior in the rabbit; animals with an- 

 terior lesions did not survive long enough to be tested 

 for the mating response. In both the rabbit and the 

 cat it is apparent that the common basal tuberal area 

 which controls the release of pituitary ovulatory 

 hormone is not a center of influence on mating be- 

 havior but that a behavioral center exists rostral to this 

 region in the cat and caudal to it in the rabbit. 



A similar duality of gonadotrophic and sex ije- 

 havioral centers in the male has recently lieen re- 

 ported for the rat by Rogers [quoted by Goldstein 

 (35)]. Premammillary lesions reduced mating be- 

 havior but it could be restored with gonadal honnones. 

 Rats with "tuberal lesions' showed a behavioral loss 

 which could not be reversed with androgen. These 



