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Amitosis in Human Adrenal Cells

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Amitosis in Human Adrenal Cells Histol Histopath (1991) 6: 251 -256 Histology and Histopathology Amitosis in human adrenal cells Maria C. Magalhies, D. Pignatelli and M.M. Magalhies Institute of Histology and Embryology of the Faculty of Medicine and Center of Experimental Morphology of the University of Oporto (INIC), Porto. Portugal Summary. Adrenal pieces obtained from 3 fcmalc ancl 2 (cr!'l~to~i~itosi\)(Elias ancl Hyde. 1983). Yet. for other ~nirlepatients sho\\'cd morpl~ologicirlfigures of umito4is a~lthors.amitosis i4 OIII!, ohscrvecl in lower invertebrates in aclrcnirl zona retic~~l:~riscclls. Such aspects were or ~~nclcrp;rtliological conditions (Yicluan and Hinkung. ohscr\~~~clin both normal and hyperactive aclrcnuls. 1086). This ma!, hc the reason wh! there 112s been :I Nuc,lci appeal-cd constricted. hea\ ill stained. decrease in ~rmitosi4~.csearch (Yinclu~un ancl Bink~rng. \\.it11 coarse chromatin. sometimes scattered among I OSCl) . c!toplasmic organcllcs. hut never niarginating in .l'hc 1lt1r\x)sc oftthe present report i\ to clcscrilw cre4ccntic cirps. mol-p11ologic:ri acll-cnal nuclcur aspects. not !,et ol3ser\,cd C'lea\:~gc 01' the cells originated t\\lo hnl\,cs \\it11 a in li~~rnan:~drenaI. ancl to cliscuss their possillle 1'~1nctionaI nucleolus in each pole. Rin~lcleateclcclls \vcl-c also seen significance. in zona rcticularis. -1~Iie meaning ot' nmitosis in human aclren:rl i4 Materials and methods cIisc11~4ccI. FIurn;r~i aclrCn;ll tissue was obtainctl from t\vo nl:~le Key words: Human adrenal. Aniito5is. Ultra4tr11ct~11-C p;lticnts agecl 32 and 43 ancl three l'cm:rlc patic~its~rgcd IS. I9 ancl 71. 'Thc~male p~~ticntssufI'el.cd from B~~ergc~-'s Introduction dise~~se.tll~. two !.oLlngcr \\omen from ;rcroc!,;~nosis ancl the older OII~from :I virilization a!.nclrome. The patients In recent !'cars little attention has been paid to the received thiopentc~nc (Pentotlial). s~~ccin!Icholinc biological meaning of aclrennl cell division. (Scolinc). di~rll!-nor-toxiferine (Allofcrine). and Latcl!:. \\,c ha\e hacl thc opport~lnityto stutl) the pctliirlinc as ;rn;~t.sthctic drugs. Patients ~~ncler\\~cnt ~~irc~irlcortex fro111 ;I woman \vho untlerwent ~lnilatcral ~~tlrenalcctomyas therap! for the disease. adrenalcctom! as therap!. for virilization 4yntlromt.. We Immetli~rtcl! ~~l'tcrremoval. adrcnals were cut into tia\,e found a special t\.pe of nuclear morphology \vhich small piece4 and irnmersecl in Bouin's solulion ior seemed to be figures of amitc>sis (Prenant et al.. 1004: light mic1-o4cop! ~rnrl 2.5%) glutaraldeliycle in 0.1 M Hueher. 1047. IO(2. 1963: Ohr2 et al.. l96(>: Pessacq. cacc~d!.late IILI~~CI-fol-electl-onmicroscopy: the tr;~gments 1900: Tippit Lrncl Pickctt-Heaps. 1976: Ferg~lsonirntl fixed in gl~lturaldeh!~dcwere postfixcd in 1':6 osmi~lm Palm. 1976: Rargmann. 1977: Tucker et :[I.. 1980: Chrn tctrosidc in \~eronal-;rcetateI~LI~~CI-. After deh!dr:rtion and Wan. IOSO). Such peculiar aspects wcrc further sccn in 21 g~-adedscric4 01' cthanols. the specimens \\.ere in human adl.cn:rl of t\vo male patients who t~nclc~.uent cmbetlcled. rcspecti\,cly. in paraffin ancl Epon 812. unil~rteral aclrcnalcctomy as therap!, for Rucrgcr's Semithin 4cctions. 1 or 2 pm thick were stai~rctlwith disease and in two female patients \\.it11 acrocyanosis. metl~!Icncbluc-~/LII-I1 (Richartlson et al.. 19hO). Somc a~~thorsdeny the occurrence of amitosis in Ultrathin sections were doul3le stained with uranyl nianlm~tls (C;r),nfeltt. 1032: Obcrling and Rcl-nhard. acetate ant1 lead citrate and the specimens were ollscr~ed 1001: Buchcl.. 1003. 1963). whereas others consider that in a Scol 100 L3 electron microscope. it i4 the onl!. t!pe of nuclcar division in adult normill li\.er Results Offprint requests to: Dra. Mar~aC. Magalhaes, lnst~tuteof Histology By light rnicl-oscopy. the adrenal cortex looked and Embryology, Faculty of Med~cine of Oporto. 4200 Oporto, no~.rnalin both n~alcpatients and in the t~oJoungest Portugal women suffering from :rcrocq.:rnosis (Fig. l). In the Amitosis in human adrenal Fig. 1. Adrenal cortex from a woman aged 18. Adrenal cortex looks normal. A small area of adrenal niedulla (M) is present. (H + E) X 360. ZG - zona glornerulosa: ZF - zona fasciculata: ZR - zona reticulans. Fig. 2. Adrenal gland from a woman aged 21 with virilization syndrome. Hypertrophy of zona reticularis (ZR) IS evident. (H + E) u 240 Fig. 3. Zona reticularls. Constricted nucleus (arrow). (H + E) u 1,470. Fig. 4. Apoptos~s. Note heavlly stalned nuclel (arrows). (H + E) 1,470 \vornan with \.irilization \ndrome. thc Iona reticulal-is (Fig. 4). Somc apoptotic boclics appeared to pas4 into scenied larger (Fig. 2). the sinnsoids. In all patients images of binuclcatcd cells ucre By electron microscopy some nuclci cshihitcd observed in thc :~drenal cortex. most of them being coarse chromatin pattern and perinuclc;~r chromatin located in the zone I-cticularis. and the zona fascic~l- appcared heavily stained. The do~~blt:IILICIC;I~ lata: sometimes nuclei were dumb-bell-sliapcd (Fig. 3). membrane was sometimes discontinuous. and denw Though seldom seen. cells undergoing apoptosis and chromatin masscs lay among cytoplasmic orga~icll~s apoptotic bodies were observed in thc zone reticularis (Fig. 5). Only a few images of karyorrlicsis ucrc Amitosis in human adrenal Fig. 5. Virilization syndrome. Complex structure of a cell nuc (N). Dense chromatin masses lie among cytoplasm organelles (arrows). x 15,000. nu - nucleolus. observed. Chromatin never marginated in crexentic On the other hand. for many authors, amitosis only caps, like the morphological feature of apoptosis in occurred in lower invertebrates, aged cells or in electron microscopy. Sometimes a constriction appeared pathological conditions (Prenant et al., 1904: Bucher, in the nuclei and two daughter nuclei appeared to be 1963): for others, it was even considered as the only type formed (Figs. 6-9). The cells showed a cleavage furrow, of nuclear division in normal adult liver (Elias and Hyde, the nucleus being perpendicular to it (Figs. 6-9): the 1982). In addition. amitosis has been studied in living cleavage deepened and widened, the neck decreased in cells cultivated in vitro (Bucher, 1963). and Bargmann diameter becoming *stretched>>along the longitudinal (1977) referred to the fact that it was often seen in highly axis of the cell (Figs. 6. 7). Such a cleavage may lead to differentiated tissues, such as the liver, heart and kidney. the formation of two sometimes unequal halves with one Accordingly, amitosis, in the classical sense. does seem nucleolus in each pole of the nucleus (Fig. 6) and. in the to play a role in the multiplication of cancer cells; a end, nuclear fission would seem to occur. No chromo- desdifferentiated cell (Oberling and Bernhard. 1961). somes were detectable within the nucleus at any stage. Concerning the adrenal, amitosis has been observed in The nucleolus in cells with a bilobate appearance of interrenal tissue of Rana temporaria (Pehlemann. 1068) amitotic division was well preserved, and contained and in rat adrenal zona glomerulosa after a prolonged fibrilar centres (Fig. 6). Nucleolar material was never low-sodium diet (Palacios et al.. 1976), but it has never scattered through the cytoplasm except in karyopyknosis. been reported in human adrenal cortex. as far as our Cytoplasmic organelles were well preserved and literature suggests. bundles of parallel microtubules were never visible near In this manuscript, morphological aspects of nuclei, the nucleus. which might be considered suggestive of amitosis. were observed in human adrenal zona reticularis. a Discussion differentiated zone of low mitotic activitj (Ford Amitosis or direct division (Prenant et al., 1904; and Young. 1963: Wright, 1971), but which in some Obre et al., 1966) has been postulated as a form of cell circumstances can be stimulated and submitted to an division, and in many cases it appears to be a kind of increased metabolic activity. physiologically-induced tissue proliferation (Yiquan Curiously enough, the zona reticularis is also the and Binkung, 1986). However many questions exist with cortical zone which exhibits more apoptotic bodies; a respect to the significance of amitosis, and even today sign of programmed cellular death (Wyllie et al., 1973, there is no truly satisfactory research concerning this 1980). However, apoptosis has peculiar morphological type of cell division (Bucher, 1963). In fact, large aspects which are easily distinguished from those of numbers of observations described as amitosis were amitosis. such as margination of chromatin in crescentic really not, often merely being artifacts of fixation, caps and cytoplasmic densification. mechanical influences. etc. (Bucher. 1963: Puza. 1969). Molecular mechanisms of amitosis in mammals are Amitosis in human adrenal Flg. 6. Zona retlc~llarlsfrom the adrenal cortex of the woman wlth v~rll~zatlon syndrome A constrlctlon (arrows) provokes the appearance of two unequal halves of the nucle~(N N') with one nucleolus (nu, nu') In each pole X 10 800 Fig. 7. Buerger's disease. Man aged 23. A cleavage furrow IS observed (arrows), the nuclel [N and N') belng perpendicular to t. 15,000 u~ihnown: in fact. \ve tlo not hno\\ \\li;~t hilitl ol might he intCrprclctl a\ :~mirosiswere scarce*. inductive signal can cause initiation of' arnitosis: We can slxu~latethat amitosis. like apoptozi4. neither do we know if amitotic nl~cleu\i3 cuploid or 0cc111.s in :~tlrcnal~.cticular cclls as part of tlici~~io~'ni:rl suffe1.s subsequent degeneration. In tlic prc\cnt tlc\,clopmcnt ancl i\ ~lrohahly correlatecl \\it11 :In study lrmitosis was ob\ervecl both in nc~rrii:~land in acti\ation ]Truce\\ or nnc Ic;rcling to cell dc:rth. in hyperacti\,c adrenal. and in both ~nirle\and fe~m:~lcs. rclalion to the maturation \t;rtc ol' thc glandular cell.
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