THE MAMMALIAN OVARY 



William C. Young, Ph.D. 



PROFESSOR OF ANATOMY, UNIVERSITY OF KANSAS, LAWRENCE, KANSAS 



I. Introduction 449 



II. FOLLICULOGENESIS 451 



A. Growth of Primary and Small Ve- 



sicular Follicles 451 



B. Growth of Vesicular Follicles 455 



C. Preovulatory Swelling 455 



1). Ovulation . ." 456 



E. Folliculogenesis in Pregnancy and 



Lactation 457 



III. Corpus Luteum 459 



IV. Follicular Atresia 4(11 



V. Hormones of the Ovary 4(i4 



A. Sites of Origin 466 



B. Amounts of Hormone Produced. . . . 471 

 VI. Age of the Animal and Ovarian 



Functioning 476 



VII. Other Endocrine Glands and the 



Ovaries 478 



A. Thyroid 478 



B. Adrenal Cortex 480 



VIII. Concluding Remarks 483 



IX. References 484 



I. Introduction 



Despite the impetus given to the study of 

 ovarian structure and physiology by the 

 work of Edgar Allen and Edward A. Doisy 

 in the 1920's, knowledge of the mammalian 

 ovary has hardly progressed beyond a de- 

 scriptive phase. This cannot be attributed to 

 lack of effort, although it must be realized 

 that the ovary as an object of investigation 

 has not held its own with the hypophysis, 

 the thyroid, the adrenal, and the testis. Nor 

 lias there been any failure to apply new 

 techniques to the many problems of ovarian 

 structure and physiology. Histochemical and 

 cytochemical techniques were seized ujion 

 for what they might contribute to the prol)- 

 lem of the site of hormone production,^ and, 



' Demp.sey and Bassett, 1943; Dempsey. 1948; 

 Claesson, 1954; Claesson and Hillarp, 1947a-c ; 

 Claesson, Diczfalusy. Hillarp and Hogberg, 1948; 

 Claesson, Hillarp, Hogberg, and Hokfelt. 1949: 



in at least one series of studies (Zachariae, 

 1957, 1958; Zachariae and Jensen, 1958; 

 Jensen and Zachariae, 1958), to the mecha- 

 nism of ovulation. Methods for obtaining 

 blood from the ovarian vein have been de- 

 vised (Paschkis and Rakoff, 1950; Rakoff 

 and Cantarow, 1950; Xeher and Zarrow, 

 1954; Edgar and Ronaldson, 1958) and re- 

 fined techniques for the assay of secreted 

 estrogens and progesterone have been de- 

 veloped (Reynolds and Ginsburg, 1942; 

 Hooker and Forbes, 1947; Emmens, 1950a, 

 b; Haslewood, 1950; Wolstenholme, 1952; 

 Zander and Simmer, 1954; Brown, 1955; 

 Loraine, 1958; Sommerville and Deshpande, 

 1958j . The collection of follicles and corpora 

 lutea timed more accurately with respect 

 to the moment of ovulation has become pos- 

 sible, and distinction between the normal 

 and the pathologic has become clearer 

 (Deane, 1952). Recently, the electron mi- 

 croscope has been found to have a place, 

 in an investigation of the finer structure 

 of the cells of the corpus luteum (Lever, 

 1956), in the unraveling of the jirocesses 

 whereby the zona pellucida is formed 

 around the developing oocyte (Chiquoine, 

 1959; Odor, 1959), and in studies of ovarian 

 oocytes and unfertilized tubal ova (Odor, 

 1960; Odor and Renninger, 1960) (see Figs. 

 14.6 to 14.8). As Villee has indicated in his 

 chapter, great strides have been taken to- 

 ward an understanding of the metabolic 

 pathways in estrogen and progesterone syn- 

 thesis and degradation. 



Two factors may have contributed to the 



McKay and Robinson, 1947; Meyer and McShan, 

 1950; Barker, 1951; Rockenschaub, 1951; White, 

 Hertig, Rock and Adams, 1951 ; Deane, 1952; Nishi- 

 zuka, 1954; Ford and Hirschman, 1955; Noach and 

 \an Rees, 1958. 



449 



