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Anterior Pituitary Body and Its Relation to the Reproductive Function

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Anterior Pituitary Body and Its Relation to the Reproductive Function University of Nebraska Medical Center DigitalCommons@UNMC MD Theses Special Collections 5-1-1934 Anterior pituitary body and its relation to the reproductive function Harold A. McConahay University of Nebraska Medical Center This manuscript is historical in nature and may not reflect current medical research and practice. Search PubMed for current research. Follow this and additional works at: https://digitalcommons.unmc.edu/mdtheses Part of the Medical Education Commons Recommended Citation McConahay, Harold A., "Anterior pituitary body and its relation to the reproductive function" (1934). MD Theses. 337. https://digitalcommons.unmc.edu/mdtheses/337 This Thesis is brought to you for free and open access by the Special Collections at DigitalCommons@UNMC. It has been accepted for inclusion in MD Theses by an authorized administrator of DigitalCommons@UNMC. For more information, please contact [email protected]. rold A. I"cOona hay iLPRIL 1934 (a) ~. ~'Iypophys is t Antal' lor lobe (fema le ) B. Genital Hormones C. Ijrowth Horn:ones D. Synergistic Hormone .3 • Thyra i d r; land }'. (Iva la t ion::::orr:nne G. Luteinization Hormone E. (lvary I. 3uprarenal Glands J. ~raafian Follicles .K. J 0 rp us :L tl t e um L. ::Jornif iea t ion r. Hormone "A!1 II. iOl'MOne tlBIf 0. ttlC if iea t ion P. Vaginal l'uensa 1. Inhibitory ~ormone (b) INTRODUCTION The outline of this work follows in secuential order the functional phases of the female mammalian organism--puberty, menstruation, pregnancy, lactation and menopause. These physiologic phases are lnainly governed by the development, and later decline of ovarian function, which is in turn, controlled by fluctuations in function of the anterior pituitary lobe, and other related glands of internal secretion. This monograph is a survey of the literature the purpose of which i5 to correlate the evidence wbicb leads to our present concept of the anterior pituitary body, and its relation to the reproductive function in female animals. The clinical apDlication of our present knowledre is limited and has led to many conflicting results. However, judging from the rapid advancement in the past, we are safe in predicting a very fruitful future especially with endocrine therapy. I c~10se this sub je c t to fa.:m i letr ize elf Witll a sctb,jGct excee d i1121 'l fac ina t 1 arlfJ ealing, and, one whiJh ie rapidly ".. ~' ~ becomin? pnpular both in the early Taco itioD of CLinical syn- drOEBS as well ~s vnrable t reapeutic results. ~~naocrillology is in its LnffHwy '~lIld is in ti1.€ experimental sta ~ypical clinical cases relative tn this particular sub- ject were Gnt available, consequently laborat0ry anirals and experirental resetlts (U;:,VCJ been s tit:.1teci. (c .) His to I" i ca 1 .... lO .... '" •• '" •• " •• " ....... '" • " " " .. " ...... '" •• 1 ii.na torny .. " .• " •• " • " •• " " • " ••• " •• " • " " " " ..... " " " " " .... 2 Puberty •.................•.....•..•....•..••... 4 ,- ImI.l1anta t ion J;xperiments. " " " ••• " • " ... " " " • " " " ., ••• 0 Feeding Experiments ............................ 10 Hy'pophysectomy. "'" •• """"."" ... "" .. """ •• ,, •• ,,",, .. " .... 12 Cas tll:a tee" • " " " " " " " ..... " ., . " ... " " " '" ..... " ., ... " " " " " . " " • " 13 '1: he Sex Hormones •...•...•..•.....•.....•...•... 17 cheim-~ondek Test ........•.......•........•.• 20 Pr~egna.ncy C.hunges""""""""" .. " .. """"" .. """".,,,, ..... ,, 22 L~.lcta t ion. " " " " . " " ... " • " " ..... " .. " .... " " " " .. " " " • " " "" ,,26 l:~enOl,)~::ll1Se" •• " • " ......... " " " " " " .. " " " " " .. " ... " " " " .. " " ... 28 i..50nc 1 us ion" " " " .. " " .. " " .• " " .. " " • " • " .. " " • " " ...... " ..... 29 Bi bl iogr~apflY" . " " " " " ..... " " • " .. " " " ....... " " .... " " .. .- .. • 3C' ( d) 3:ISTORICAL Our earliest conception of trle function of the pi tui tary gland came from Galen. ~is idea wes that it acted as a filter for the sedimented waste nroducts of the brain and that these passed out through the infundibulum as a "pituita" or slime from the nose. As late as 1631 Robert Flood explained the etiology of coryza on the principle of a siphon action between the ven­ tricles and the nose. In Thomas Gibson's anatomy (lS88) it is inferred that in animals such as calves, who have a large pit­ ui tary \,li th rich arterial supTlly the gland seems to have the same relationship to the arterial plexus as the pineal body has to the choroid plexus; its purpose is to separate serous fluid f'rOT., t he lymph. Very little progress was made in the study of the pituitary body until Pierre Marie (1866) (98) made the discovery that acromegaly was associated with tumors of the gland. This bril­ l iant observation was confirmed by rankous}~i (1887) and T!lany other investigations since. It turned a new page in the history of hypouhyseal ~hysiology. To be sure acromegaly and gigantism were recognized as clinical entities knOWT to be associated with hypophyseal tume­ faction. (Pierre Marie (98) and !,:inkouski (41), but Pechkranz (1899), Frolich (1901), Axenfeld (1903), :'uller (1905) (108) and others were calling attention to existence of tumors of the gland or its neighborhood associated with combinations of optic atronhy, amenocrhea, infantilism, adiposity, and often, diabetes insipious. A relationshIp betweeL the hypophysis, and genitalia 2 was, consequently, inferred, but not understood •. As early as 1898 following the work of Howell (86) special attention was given to individual lobes of the gland. Much ex- - perimentationhas been done since to determine the effects of extirpation of the whole gland or :part of the gland, feeding the se-r;arate lobes together atd separately and the administration of extracts of the various lobes individually and collectively •. Prior to the work of Paulesco (1907) (113) a Roumanian in- vestigators , the generally accepted opinion was that the pit- uitary body was a vestigial structure and of no consequence to the organism.. Total extir9ation of the hypophysis of experimental dogs resulted in their death. Thus, he concluded that the nituitary gland is "essential to life~ Crowe (25), C~shing (27) and ~~omans (1910) (85) reDorted the compl ete removal of the anterior lobe alone resulted in a characteristic train of syru- ntoms termed, tl Ca chexia-pl1Yilopl1yeopri va," resul t lng in death of the animals, therefore confirming Paulesco's (113) observat- ions. Before proceeding with the main issues of t~is paper it will be necessary to briefly review the a~atomy and histology of the pituitary g19nd. It is an ovoid shaped mass about the size of a pea; situated within the sella tutcica at the base of the brain just behind the optic chiasm. rpon sagittal section the gland is seen to consist of an anter10r and a posterior nortion. The anterior lobe or pars anterior is larger and has a - ,slaLQular structure. Embryologically it does not belong to tbe brain but is developed from a ~ouch in the oriffiitive oral cavity. It is without B duct, as it is one of the glands of internal secretion. Histologically tbe glard is composed of three parts: (1) the largi anterior epithelial lobe, pars anterior; (2) a much s!Iialler Dars nervous or infundIbular, pars posterior, aLd; ( (3) the pars intermedla. The ectoderm of the mouth (Rathkes pouch) origir:ates the anterior lobe which soon becomes a glandular structure. An outgrowth from the floor of the infundibular pouch of the telmencephalon, the mid-brain, develops the posterior lobe. The posterior lobe consists of two parts: (1) the neu­ roglia cells and fibers with ependymal cells and; (2) the pars intermedia composed of epi thelicll cells from a diverticulum of buccal epithelia, the posterior pharynx and is ectodermal in origin. The anterior lobe contains cells which are clear in hold, in their protoplasm v0rying amounts of granules, which stain deeply. It contains three kinds of cells: (1) the "haupt­ zellen," (2) eosinophiles, (3) baso-philes. Erdheim and stumme (51) call the eisino::hiles or acido]?:tliles and basoLJhiles or cyanophiles because their proto-plasITl intersely takes the staJ ns, the chromophiles, while the "Hauptzellen" they call chronrphobes because their protoplasm is difficult to stain. Rasmussen (115) by means of reconstruction of cross sections of many glands, determined the relative number of these cells. He found ttat the chroTliophobe cells make up the largest percen­ tage (52%), the eosffiophiles occurred in 37% and the basophiles 11%.] In advanced age the chromophiles were unchanged. The eosinophi les are located in greater number In the anterior '.or­ tion of this lobe near the margins of the alvoeli. The ohromo­ phobes and basophiles are Jocated in the center of the columns and are present in large numbers in the ,osterior part and near the stalk of the infundib~pl. 4 The im~ortance of these cells in the secretion of the hy­ pophysis, and their relationship to the general metabolism of the orf8Lisru. has been 11he subject of much spececlation and experimentation"during the past decade. W. P. Covell (24) has shown th9t the growth in weight of the anterior hypophysis during embryonic and early fetal periods is very rapid. The hypophysis and its lobes grows in weight similar to the increased weight of such vital structures as eyeball and mid-brain. The hypophysis of the full term fetus, consists mostly of pars anterior, roughly 78% (2% pars interr:ledia, 20% pars nervosa.) The generative glands of the embryo is under the influence of the maternal pituitary and the eer characteristics
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