Adrenal and ovarian sources of progesterone secretion in young female fallow deer, Dama dama

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Philomena Dixon
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1 Adrenal and varian surces f prgesterne secretin in yung female fallw deer, Dama dama G. W. Asher, A. J. Petersn and D. Duganzich Ruakura Agricultural Centre, Ministry fagriculture and Fisheries, Private Bag, Hamiltn, New Zealand Summary. Six yung female fallw deer, including 3 that were variectmized at 9 mnths f age, were bld sampled at frequent intervals after i.v. injectins f (1) ACTH analgue (tetracsactrin), (2) GnRH analgue (buserelin) and (3) saline slutin n separate ccasins at 11, 13, 15 and 18 mnths f age. Relative t pre- increase in challenge plasma values, ACTH administratin resulted in a 4\p=n-\10-fld mean plasma prgesterne cncentratins, but nly a 10\p=n-\45% increase in mean plasma crtisl cncentratins, within 40 min fr entire and variectmized des during the prepubertal perids (11, 13 and 15 mnths) and fr variectmized des during the pst-pubertal perid (18 mnths). Pst-pubertal entire des exhibited high mean basal plasma prgesterne cncentratins (3\p=n-\4ng/ml) indicating a luteal surce f secretin, with the ACTH-induced prgesterne respnse being additive t the luteal prgesterne but f similar magnitude t respnses in the variectmized des. There was n significant ACTH challenge effect n mean plasma LH cncentratins fr entire r variectmized des at all ages. GnRH administratin had n significant effects n mean plasma cncentratins f prgesterne and crtisl f entire and variectmized des, althugh there was a small increase in mean plasma prgesterne values in pst-pubertal des that may have reflected a luteal respnse t GnRH (via LH). GnRH challenge resulted in marked increases in mean plasma LH cncentratins but the respnse patterns were different fr the 2 types f des, being mre rapid and f higher magnitude fr variectmized des. Saline injectins had n significant effects n mean plasma hrmne cncentratins fr entire and variectmized des at any age. It is cncluded that the adrenal glands are secndary and majr surces f prgesterne in fallw deer and that there exists a tw-phase respnse f adrenal glands t stress/acth stimulatin in terms f crtisl and prgesterne secretin. Keywrds: fallw deer, prgesterne, crtisl; adrenal gland; crpus luteum Intrductin The crpus luteum appears t be the principal surce f prgesterne in female deer, particularly during the estrus cycle (e.g. fallw deer, Dama dama: Asher, 1985; Asher & Smith, 1987; red deer, Cervus elaphus: Adam et al, 1985; Pere David's deer, Elaphurus davidianus: Curlewis et al, 1988; white-tailed deer, Odcileus virginianus: Harder & Mrhead, 1980) and early pregnancy (e.g. fallw deer: Asher, 1986, 1987; red deer: Kelly et al, 1982; Adam et al, 1985). Hwever, certain anmalies in plasma prgesterne cncentratins bserved ccasinally in female red deer and fallw deer cannt be explained in terms f luteal secretin f the hrmne. Kelly et al (1985)

2 recrded erratic fluctuatins in plasma prgesterne cncentratins during the peri-estrus perid f mature red deer hinds. Similarly, a single shrt-duratin (2-3 h), high-amplitude (> 5 ng/ml) pulse f plasma prgesterne was bserved at the nset f estrus f a mature fallw de (Asher et al, 1986). Unusual incidences f prgesterne secretin are nt cnfined t adult female deer. Asher (1986) recrded an increase in mean plasma prgesterne cncentratins, frm 0-5 t 20 ng/ml, in immature fallw des between 10 and 15 mnths f age and erratic fluctuatins in plasma prgesterne cncentratins (up t 7 ng/ml) ccurred in twice-weekly samples frm immature des (Asher et al, 1988b). As significant quantities f active luteal tissue are unlikely t be present befre sexual maturity r during the peri-estrus perid, it seems likely that the prgesterne bserved in these studies was derived frm extra-varian surces. Prgesterne is knwn t be secreted in significant amunts by the adrenal glands f rats (Resk, 1969; Fajer et al, 1971), ewes (Green & Mr, 1977) and cws (Gwazdauskas et al, 1972; Wagner et al, 1972). Furthermre, Wessn et al. (1979) bserved a significant rise in plasma prgesterne cncentratins in female white-tailed deer 30 min after immbilizatin with the muscle relaxant, succinyl-chline chlride, and cncluded that increased stress while under nnsedated chemical restraint resulted in increased adrenal secretin f prgesterne. Frm a series f experiments invlving the use f anaesthetic drugs and ACTH stimulatin/dexamethasne depressin f adrenal activity, Pltka et al (1983) prvided further evidence f adrenal prgesterne secretin in female and male white-tailed deer. These studies lend supprt t the hypthesis that the adrenal glands may be a secndary surce f prgesterne in fallw deer (Asher, 1986). The present study aimed t test this hypthesis fr entire and variectmized fallw des between 10 and 18 mnths f age by measuring the hrmnal respnses t ACTH-analgue challenge f adrenal tissue and GnRH-analgue challenge (and hence LH challenge) f luteal tissue. Materials and Methds Animals and management. Six immature fallw des, brn in December 1985, were selected in July 1986 (8 mnths f age) at a unifrm liveweight (25-27 kg). Three f the des were variectmized n 13 August (9 mnths) using anaesthetic and surgical prcedures similar t thse described by Asher et al. (1988a) fr hysterectmy surgery n adult des. The deer were cntained in high-fenced paddcks with 18 ther des f the same age and were grazed n ryegrassclver pastures. Bld sampling. During the mnths f Octber (11 mnths), January (13 mnths), March (15 mnths) and June (18 mnths, after sexual maturatin) the 6 des were held indrs frm 08:00 t 17:00 h (9 h) n 3 separate ccasins and subjected t an intensive bld sampling regimen fllwing physilgical challenges with ACTH analgue, GnRH analgue r saline slutin (i.e. cntrl). On 7 Octber, 14 January, 31 March and 8 June each de received an i.v. injectin f 125 µg tetracsactrin (0-5 ml Synacthen: Ciba Geigy Ltd, Basle, Switzerland) at 09:00 h. They were bld sampled at -60, -40, -20, 0, 10, 20, 40, 60, 90, 120, 150, 180, 240, 300, 360 and 480 min frm the challenge. The entire prcedure was repeated frm an i.v. challenge f 4pg buserelin (10 ml Receptal: Hechst Veterinär GmbH, München, FRG) n 29 Octber, 7 January, 25 March and 15 June, and fr an i.v. challenge f 10 ml saline slutin (9 g NaCl/1) n 16 Octber, 21 January, 3 April and 19 June. The des were bld sampled (5 ml) by jugular venepuncture (21-gauge needles) int heparinized Vacutainers while individually restrained in a cradle device. Their necks had been shaven previusly t facilitate venepuncture frm the right external jugular vein. Intravenus injectins were administered int the left external jugular vein. Bld samples were centrifuged immediately after cllectin and the plasma was stred at 10 C until assayed. Hrmne assays. Plasma samples (n = 1152) were assayed fr prgesterne, crtisl and luteinizing hrmne (LH) by radiimmunassay techniques. Plasma prgesterne cncentratins were measured by a prcedure similar t that described by Fairclugh et al. (1975a) and validated previusly fr fallw deer serum (Asher, 1985). The antiserum was raised in a rabbit against prgesterne-11-bsa cnjugate and used at a final dilutin f 1:3000. The nly significant crss-reactin f a wide range f sterids, including crtisl, tested in the assay was chlesterl (1-5%). Sensitivity f the standard curve was 003 ng per tube (015 ng/ml plasma) and the intra- and inter-assay cefficients f variatin were 6-2% and 15-8% respectively.

3 Plasma crtisl cncentratins were measured by a prcedure similar t that described fr prgesterne (Fairclugh et al, 1975b). The antiserum was raised in an variectmized ewe against crtisl-3-cmo-bsa and used at a final dilutin f 1:3000. Crss-reactivity with ther sterids ccurred t the fllwing extent: dexy-17- hydrxycrticsterne 5-7%, crtisne 1-2%, crticsterne 0-8%, dexamethasne 0-02%, dexycrticsterne 0005%, prgesterne and all ther sterids tested <0005%. The mean recvery (+ s.d.) f crtisl added t charcal-stripped plasma was 94-8 ± 101% at 50ng/ml (n 50 determinatins), ± 13 3% = at 100ng/ml (n 48), ± 14-4% at 200 ng/ml (n 47) and 90-0 ± 12-8% = = at 500 ng/ml (n 32). Extractin efficiency f = radiactive crtisl in plasma was 94-2 = + 2-7% («10 determinatins). AH samples frm an individual challenge were included in a single assay. The inter-assay cefficients f variatin were 10-6%, 13-2%, 14-4% and 14-4% fr 50, 100, 200 and 500 ng/ml cntrl samples respectively. The intra-assay cefficient f variatin, calculated frm multiple determinatins f the 100 ng/ml cntrl sample was 8-8% and the sensitivity f the standard curve was OlOng per tube (10 ng/ml plasma). Luteinizing hrmne (LH) cncentratins were determined using a heterlgus radiimmunassay prcedure described fr sheep plasma by Scaramuzzi et al. (1970). The entire assay has been validated previusly fr fallw deer serum and plasma (Asher el ai, 1986). Sheep pituitary LH preparatins used fr standards and idinated tracer were NIH-LH-S 11. The LH antibdy, which had been raised in a rabbit als using NIH-LH-S11 as the antigen, was used in the assay at a final dilutin f 1: Crss-reactivity with ther prteins has been described previusly (Kelly et al., 1982; Asher et al, 1986). Serial dilutins f pled serum r plasma frm estrus des with high cn centratins f immunreactive LH gave inhibitin curves parallel t thse generated fr NIH-LH-S11 in buffer (Asher et al., 1986). The inter-assay cefficients f variatin, calculated frm determinatins f sheep (mean cncen tratin = 4-8 ng/ml) and deer (mean 3-2 ng/ml) cntrl samples in each = assay (n 4 assays) = were 12-7% and 14-2% respectively. The intra-assay cefficients f variatin fr multiple determinatins f the same cntrl samples were 5-2% and 7-0% respectively. The sensitivity f the standard curve was 003 ng NIH-LH-S 11 per tube (0-30 ng/ml). Statistical analysis. The data were lg-transfrmed and subjected t analysis f variance in which challenge type (ACTH, GnRH and saline), age (11, 13, 15 and 18 mnths) and their interactin, plus interactins f these with de type (entire and variectmized), were tested against crrespnding variatin between des. The data are presented graphically as nn-transfrmed means (+ 1 s.e.m.). Results Prgesterne respnses During the 3 prepubertal age perids (11, 13 and 15 mnths) there was a significant effect f challenge type (ACTH vs GnRH and saline; < 0001), but n apparent effect f de type (P > 0-1), n plasma prgesterne cncentratins (Fig. 1). Fr entire and variectmized des, ACTH injectin resulted in a 4-10-fld increase in mean plasma prgesterne cncentratins t attain peak values (4-8 ng/ml) within 40 min after challenge. The cncentratins declined prgres sively frm 40 t 180 min after challenge. GnRH challenge and saline injectin did nt result in increases in mean plasma prgesterne cncentratins during the prepubertal perid. As with ACTH challenge, mean values twards the end f each sampling sessin were generally lwer than crrespnding pre-challenge values. During the pst-pubertal perid (18 mnths) there was a significant difference between entire and variectmized des in mean prgesterne cncentratins befre and after challenge with GnRH (P < 0001), being 3-4ng/ml fr entire des and ng/ml fr variectmized des (Fig. 1). Hwever, the respnse t ACTH challenge was f similar magnitude fr bth types f des ( ~ 6 ng/ml abve respective basal values) and f similar magnitude t ACTH-induced changes bserved in the prepubertal perid. The entire des exhibited a small, nn-significant (P > 0T) rise in mean plasma prgesterne cncentratins immediately after GnRH challenge (i.e. ~25% increase) that was nt apparent fr the variectmized des r fr bth types f des fllwing saline injectin. Crtisl respnses Thrughut the 4 age perids there was n significant effect f de type n the pattern f plasma crtisl changes (P > 01) but there was a significant challenge effect (P < 0-001) (Fig. 2). Mean pre-challenge plasma crtisl cncentratins f entire and variectmized des varied

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5 between 60 and 160 ng/ml. ACTH challenge increased basal cncentratins by 10-45% within 20 min after challenge. Thereafter, cncentratins declined prgressively t reach mean values 50-70% lwer than pre-challenge values. GnRH challenge and saline injectin did nt result in any significant increase in mean plasma crtisl cncentratin (P > 01) but there was a similar reduc tin in values twards the end f each sampling sessin as ccurred during ACTH challenge sessins (Fig. 2). LH respnses There were significant challenge type and de type effects n mean plasma LH cncentratins (P < 0001) (Fig. 3). Thrughut the 4 age perids mean plasma LH cncentratins befre challenge were cnsistently higher fr variectmized des (3^1 ng/ml) than fr entire des ( ng/ml). The principal challenge effect was bserved fllwing GnRH injectin, althugh the respnse pattern was markedly different between entire and variectmized des. Mean plasma LH cncentratins fr entire des increased prgressively after GnRH administratin t attain maximal values 8-24-fld higher (i.e ng/ml) than pre-challenge values within abut 150 min. In cntrast, maximal values fr variectmized des (i.e ng/ml) were reached within 40 min. Bth types f des subsequently exhibited a prgressive decline in mean plasma LH values t reach pre-challenge cncentratins by 480 min (Fig. 3). Neither ACTH challenge nr saline injectin had any significant effects n mean plasma LH cncentratins (P > 0-1). Discussin The rapid elevatin f plasma prgesterne cncentratins in variectmized and entire fallw des after ACTH administratin clearly implicates the adrenal glands as a majr surce f the hrmne in this species. It seems likely, therefre, that the ccasinal anmalus prgesterne prfiles bserved in fallw deer, and ther cervid species, als represent adrenal prgesterne secretin in respnse t varius Stressrs. Plasma prgesterne cncentratins fllwing ACTH challenge were similar t peripheral plasma cncentratins f apparent luteal rigin ccurring during the estrus cycle (Asher, 1985) and pregnancy (Asher, 1987). Likewise, erratic fluctuatins in plasma prgesterne cncentratins during the periestrus perid f sme red deer hinds (Kelly et al, 1985) were similar t cncen tratins presumably derived frm luteal surces (Adam et al, 1985). Furthermre, adrenal glands f white-tailed deer des cntribute mre than 3 ng prgesterne/ml t the peripheral circulatry system (Pltka et al, 1983). Thus prgesterne f adrenal rigin may ccasinally cnfund interpretatin f plasma prgesterne prfiles fr a number f deer species. Fr example, high mean basal cncentratins f plasma prgesterne (3-4 ng/ml) in the entire fallw des at 18 mnths f age (Fig. Id) undubtedly reflect active crpra lutea after sexual maturatin. Prgester ne f adrenal rigin, as a cnsequence f ACTH administratin, was clearly additive t that f varian rigin, and in the absence f pre-challenge data (r indeed the effect f stress stimuli) it wuld be impssible t differentiate the relative cntributins f the tw surces f secretin. While plasma prgesterne data clearly indicate the presence f active luteal tissue in 18-mnthld entire des there is little indicatin f a majr effect f GnRH challenge (and hence, LH stimulatin) n luteal prgesterne secretin. This type f challenge may nt be a useful indicatr f the presence f active luteal tissue in mature fallw deer, as had been pstulated at the start f the trial. The cmplete failure f exgenus GnRH t stimulate prgesterne secretin in sexually immature des (i.e mnths) mst prbably reflects the absence f luteal tissue fr such tissue is nly fund after sexual maturatin at 16 mnths f age (Armstrng et al, 1969; Chapman & Chapman, 1969,1975; Baker, 1973). Hwever, plasma LH cncentratins f variectmized fallw

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des were ntably higher than fr entire des, indicating that the negative gnadal feedback n pituitary functin was effective even in immature animals.

8 des were ntably higher than fr entire des, indicating that the negative gnadal feedback n pituitary functin was effective even in immature animals. Differential respnses by variectmized and entire des t GnRH challenge indicate pssible gnadal mdulatin f pituitary respnse t GnRH that was manifest by extremely rapid, high-amplitude LH secretin fllwing GnRH administratin in variectmized des cmpared with a mre gradual, lwer-amplitude respnse in entire des. Plasma crtisl cncentratins bserved in this study were very high at the start f each bld sampling sessin and declined prgressively t attain cnsiderably lwer final cncentratins. Crtisl cncentratins did nt increase markedly in respnse t ACTH challenge, whereas thse f prgesterne did. Perhaps the high levels f stress at the start f each experiment caused maximal adrenal secretin f crtisl, such that additinal stimulatin with exgenus ACTH was withut a marked respnse. The present results suggest that large quantities f crtisl and mdest quantities f prgesterne are secreted by the adrenal crtex f fallw deer in respnse t mst stress stimuli. Hwever, under extreme stress, prgesterne, rather than additinal quantities f crtisl, is secreted in large amunts. There has been cnsiderable speculatin n hw the adrenal gland might influence reprductive functin in mammals (reviews: Parkes efe Deanesly, 1966; Mberg, 1985). Adrenal prgesterne secretin may affect varius cmpnents f the reprductive prcess. Fr example, Pltka et al (1983) pstulated that adrenal prgesterne in white-tailed deer may help t maintain pregnancy during perids f stress by neutralizing the pregnancy-terminating actin f crtisl. Alternatively, high bld prgesterne cncentratins after adrenal stimulatin may inhibit estrus and vulatin during the breeding seasn, thus preventing pregnancy under highly stressful cnditins. Our bld sampling regimen lacked sufficient precisin and duratin t detect any pssible changes in LH pulse frequency in respnse t adrenal prgesterne secretin in fallw des. Evidence that prgesterne secretin, pssibly f adrenal rigin, may affect LH secretin during the breeding seasn f fallw deer was prvided by Asher et al (1986) wh reprted a mature de with a very high plasma cncentratin ( > 5 ng/ml) f prgesterne, at the nset f estrus, which appeared t depress the prevulatry LH surge. Hwever, this situatin, and that frm the present study, nly related t transitry stimulatin f the adrenal glands, resulting in transient increases in prgesterne secretin. Sustained adrenal stimulatin assciated with envirnmental r scial Stressrs culd have mre lng-term effects n reprductin in fallw deer. We thank M. Langridge, O. C. Chitty and H. H. Humble fr assistance with animal handling and bld sampling; R. Shanley, S. Parratt and L. ter Veer fr hrmne analyses; Dr A. J. Pearsn fr useful cmments n earlier draft manuscripts; and Ciba Geigy Ltd fr the kind dnatin f Synacthen. References Adam, CL., Mir, C.E. & Atkinsn, T. (1985) Plasma cncentratins f prgesterne in female red deer (Cervus elaphus) during the breeding seasn, preg nancy and anestrus. J. Reprd. Fert. 74, Armstrng, V, Chaplin, R.E., Chapman, D.I. & Smith, B. (1969) Observatins n the reprductin f female wild and park fallw deer (Dama dama) in suthern England. J. Zl, Lnd. 158, Asher, G.W. (1985) Oestrus cycle and breeding seasn f farmed fallw deer, Dama dama. J. Reprd. Fert. 75, Asher, G.W. (1986) Studies n the reprductin ffarmed fallw deer (Dama dama). Ph.D. thesis, University f Canterbury, New Zealand. Asher, G.W. (1987) Cnceptin rates, gestatin length, liveweight changes and serum prgesterne cncen tratins during the breeding seasn and pregnancy f farmed female fallw deer. Prc. 4th AAAP Animal Sciences Cngress, Hamiltn, New Zealand, p. 247, Abstr. Asher, G.W. & Smith, J.F. (1987) Inductin f estrus and vulatin in farmed fallw deer (Dama dama) by using prgesterne and PMSG treatment. J. Reprd. Fert. Sí, Asher, G.W., Barrell, G.K. & Petersn, A.J. (1986) Hr mnal changes arund estrus f farmed fallw deer, Dama dama. J. Reprd. Fert. IS, 487^196. Asher, G.W., Petersn, A.J. & Watkins, W.B. (1988a) Hrmnal changes during luteal regressin in farmed fallw deer, Dama dama. J. Reprd. Feri. 84,

Asher, G.W., Barrell, G.K., Adam, J.L. & Staples, L. (1988b) Effects f subcutaneus melatnin implants n reprductive seasnality f farmed fallw deer (Dama dama). J. Reprd. Fert. 84, 679-691. Baker,.

9 Asher, G.W., Barrell, G.K., Adam, J.L. & Staples, L. (1988b) Effects f subcutaneus melatnin implants n reprductive seasnality f farmed fallw deer (Dama dama). J. Reprd. Fert. 84, Baker,. (1973) Reprductin bilgy f fallw deer (Dama dama) in the Blue Muntains fnew Zealand. M.Sc. thesis, University f Otag, Dunedin, New Zealand. Chapman, D.I. & Chapman, N. (1969) Observatins n the bilgy f fallw deer (Dama dama) in Epping Frest, Essex, England. Bilgical Cnservatin 2, Chapman, D.I. & Chapman, N. ( 1975) Fallw Deer: their Histry, Distributin and Bilgy. Terence Daltn Ltd, Lavenham, U.K. Curlewis, J.D., Ludn, A.S.I. & Cleman, A.P.M. (1988) Oestrus cycles and the breeding seasn f the Pere David's deer hind (Elephurus davidianus). J. Reprd. Fert. SI, Fairclugh, R.J., Hunter, J.T. & Welch, R.A.S. (1975a) Peripheral plasma prgesterne and uter-varian prstaglandin F cncentratins in the cw arund parturitin. Prstaglandins 9, Fairclugh, R.J., Hunter, J.T., Welch, R.A.S. & Payne, E. (1975b) Plasma crticsterid cncentratins in the bvine fetus near term. /. Endcr. 65, Fajer, A.B., Hlzhauer, M. & Newprt, H.M. (1971) The cntributin f the adrenal gland t the ttal amunt f prgesterne prduced in the female rat. J. Physil, Lnd. 214, Green, D. & Mr, R.M. (1977) The influence f anaesthesia n the cncentratin f prgesterne and crtisl in peripheral bld plasma f sheep. Res. vet. Sci. 22, Gwazdauskas, F.C., Thatcher, W.W. & Wilcx, CJ. (1972) Adrencrtictrpin alteratin f bvine peripheral plasma cncentratins f crtisl, crti csterne and prgesterne. J. Dairy Sci. 55, Harder, J.D. & Mrhead, D.L. (1980) Develpment f crpra lutea and plasma prgesterne levels assciated with the nset f the breeding seasn in whitetailed deer (Odcileus virginianus). Bil. Reprd. 11, Kelly, R.W., McNatty, K.P., Mre, G.H., Rss, D. & Gibb, M. (1982) Plasma cncentratins f LH, pr lactin, estradil and prgesterne in female red deer (Cervus elaphus) during pregnancy. J. Reprd. Fert. 64, Kelly, R.W., McNatty, K.P. & Mre, G.H. (1985) Hr mnal changes abut estrus in female red deer. In Bilgy f Deer Prductin, pp Eds P. F. Fennessy & K. R. Drew. The Ryal Sciety f New Zealand, Wellingtn, N.Z. Mberg, G.P. (1985) Influence f stress n reprductin: measure f well-being. In Animal Stress, pp Ed. G. P. Mberg. American Physilgy Sciety, Bethesda. Parkes, A.S. & Deanesly, R. ( 1966) Relatin between the gnads and the adrenal glands. In Marshall's Physi lgy freprductin, 3rd edn, vl. 3, pp Ed. A. S. Parkes. Lngmans, Green & C. Ltd, Lndn. Pltka, E.D., Seal, U.S., Verme, L.J. & Ozga, J.J. (1983) The adrenal gland in white-tailed deer: a sig nificant surce f prgesterne. J. Wildl. Mgmt 47, Resk, J.A. (1969) Endcrine cntrl f adrenal prgesterne secretin in the variectmised rat. Science, N. Y. 164, 70. Scaramuzzi, R.J., Caldwell, B.V. & Mr, R.M. (1970) Radiimmunassay f LH and estrgen during the estrus cycle f the ewe. Bil. Reprd. 3, Wagner, W.C, Strhbelm, R.E. & Harris, P.A. (1972) ACTH, crticids and luteal functin in heifers. J. Anim. Sci. 35, Wessn, J.A., Scanln, P.F., Kirkpatrick, R.L., Msby, H.S. & Butcher, R.L. (1979) Influence f chemical immbilisatin and physical restraint n sterid hr mne levels in bld f white-tailed deer. Can. J. Zl. 57, Received 2 August 1988

Abrupt decrease in daylength and short-term changes in

Abrupt decrease in daylength and shrt-term changes in the plasma cncentratins f FSH, LH and prlactin in anestrus ewes J. S. Waltn, Janet D. Evins, B. P. Fitzgerald and F. J. Cunningham Department fphysilgy