W T E R V I I

EFFECT OF PITUITARY EXTRClCTS ON THE SPERMATOGENESIS OF

N O R M UPFRODW

Tntroduc t i o n

The e f f e c t of implantat ion o f p i t u i t a r y and l n j e c t i ~ o f

p i t u i t a r y e x t r a c t s i n d i f f e r e n t species o f s a l i e n t i a have been

inves t iga ted by several authors (v ide General H i s t o r i c a l Resume).

The present sec t ion describes the experiments i n U~erodon svstoma

which has no t so f a r been invest igated.

Ma te r ia l s and Methods

Adul t male specimen of Uoerodon svstoma of 45gm average body

weight and 6Omm snout t o vent length were co l l ec ted l o c a l l y . The

f rogs were kept i n separate aquarla fo r quarantine and

a i c l i m l t l s a t i o n and d iv ided i n t o (a ) normal ( b ) c o n t r o l and ( c )

eyperlmental groups. Durlng the experimental perlod, the animals

were fed w i t h ants pupa and termites, ad l i b i tum.

The normal specimens were autopsied a t the commencement o f

the experiment l t s e l f t o observe the spermatogenetic condi t ions.

Ten f rogs were i n j e c t e d w i t h equal amounts o f Amphibian Rlnger s

s o l u t i o n and were Lept as placebo con t ro l s . P l t u l t a r l e s o f

mature male and female f rogs i n the r a t l o 1:l were co l l ec ted

dur ing co ld season ( "Winter" ) and preserved i n acetone a t a

temperature of 15% f o r use dur ing e,,periments. A s i m i l a r number

(280) of Pituitaries were a l so co l l ec ted durrng warmer months

("Summer") and preserved i n acetone. Ex t rac ts from equal number

of P i t u i t a r y glands o f both the sexes were administered t o the

frogs i n the experimental group.

T h e ex t rac ts were prepared by pu lve r i s ing the d r i e d mate r ia l

i n a mortar a f t e r which Amphibian Ringer 's s o l u t i o n was added.

The e x t r a c t f i l t e r e d before use was in jec ted i n t o dorsal lymph

sacs of frogs. Ten frogs were taken f o r each experimental g r w p

and each one of them received a t o t a l amount of 3.5ml of R inger ' s

so lu t ion conta in ing 14 f rog p i t u i t a r i e s ext racts . This was given

I n seven doses o f 0.5ml and i n j e c t e d every a l te rna te day over 14

days. Care was taken t o prevent the loss through per fo ra t ion

made by the hypodermic needle. On the fifteenth day o f the

experiment both con t ro l s and esperlmental frogs were autopsied.

Four se ts o f experiments were performed according t o the

fo l lowing schemes.

1. Injection o f p l t u l t a r y e x t r a c t of co ld season

( "Win te r " ) f rogs I n t o f rogs of co ld season ( "Winter f rogs") .

?. I n j e c t i o n s of p l t u l t a r y ex t rac ts of "Winter f rogs"

i n t o "Summer f rogs" (Warm season).

3. I n ~ e c t i o n s o f p i t u i t a r y e x t r a c t o f "Summer f rogs" l n t o

"Summer f rogs" .

4 . I n j e c t i o n o f p i t u i t a r y ex t rac ts of "Summer frogs" l n t a

"Winter f rogs" .

Winter a i t u i t a r v ex t rac ts on winter f roas

I n the month of January, ten f rogs were i n ~ e c t e d w i t h an

ex t rac t o f pituitaries co l lec ted dur lng the l a s t week o f

December. Normal and con t ro l s were maintalned i n separate

aquaria under ord inary room temperature. f i l l f rogs were

sac r i f i ced on the second week o f February and t e s t i c u l a r t i ssues

were co l lected.

Winter p i t u i t a r y e x t r a c t QQ summer f-

I n the f i r s t week of A p r i l a number o f frogs a r r i v e d i n the

laboratory and they were d iv ided I n t o con t ro l s and exper i~mrn t r l

groups and were kept under i d e n t i c a l condi t ions as i n the

previous experiment.

The pituitary ex t rac ts used f o r ~ n j e c t l o n I n t h i s experiment

were co l l ec ted dur ing the l a s t week of December a longwi th those

used I n the previous experiment. Ten anlmals received injections

f o r the two weeks commencing from the l a s t week of A p r i l and were

autupsled dur ing the f l r s t weel. o f Nay. A few normal anlmals

were s a c r l f l c e d a t the beginning of these experiments and 10

p a r a l l e l con t ro l s were autopsied along w l t h experlmentals.

Summer pituitary ex t rac ts on summer f rous

A number of f rogs were a lso co l l ec ted i n the l a s t week of

A p r i l and kept l n separate groups. Of these, ten experlmental

f rogs were ~ n j e c t e d w l t h p i t u i t a r y ex t rac ts c o l l e c t e d dur ing the

same month. The normal f rogs were autopsied a t the beginning o f

the experiment and f i v e f rogs were kept under identical

conditions f o r two weeks as ( p a r a l l e l ) con t ro l s w l t h experlmental

group. A l l c o n t r o l s and experimental f rogs were autopsied a t the

end o f the experiment i n order t o compare the e f f e c t s o f

p i t u i t a r y e x t r a c t i n j e c t i o n on spermatogenesis.

p ~ t u l t a r v 9 x t r a c t en winter

I n the month of December another l o t of f rogs were d ivrded

I n t o con t ro l s and exper lmmtal groups and were maintained I n

separate aquaria under unrform husbandary condltaons. The

p l t u l t a r l e s co l l ec ted dur lng the month of A p r l l were l n j e c t e d

i n t o t h l s group of experimental f rogs co l l ec ted dur lng winter

months. Contro ls and the experimental frogs were autopsied on

the second week of December.

The test15 c o l l e c t e d from the f rogs i n the abave experlnents

were f i )<ed I n Bouin, sectioned a t 7 u and sta lned w l t h hammalum

eosln. The r e l a t l v e t e s t i c u l a r welght was noted. The

spermatogenetlc a c t i v i t y was q u a n t i t a t i v e l y assessed as per the

previously stated method. (Vlde PageNo 35 ) .

OBSERVATION

The q u a n t l t a t l v e h l s t o l o g l c analys ls of the different stages

of spermatogenesls I n U~erodon svstoma reveals t h a t

spermatngenesis I n t h i s f rog species 15 probably of continuo-

discontinuous type. Spermatozoa and spermatlds are present I n

low l e v e l dur ing wlnter months of the year. Prlmary

spermatogonla (Stage 0 ) i n a few f rogs shows m l t o t l c d l v l sxon and

proceeds t o the development of prlmary spermatocytes. The

spermartogenetic a c t l v i t y resurges dur ing sp r ing months (March)

and proceeds a c t l v e l y through summer season and spermlatlon 1s

observed ~n June-July. Thereafter act ive, spermatogenesls

progressively regresses.

Winter F r m Par.llel r o n t r o l Table lb F i g 36

Frogs co l l ec ted dur ing wintmr months ( f i r s t f o r t n i g h t of

December) served as c o n t r o l f rog f o r v r n t e r season. A

q u a n t ~ t a t i v e h i s t o l o g l c a l study revealed t h a t the saminiferous

tubules are f i l l e d predominantly w l t h primary spermatogonia and

few c e l l nests of secondary spermatogonial and primary

spermatocytes. Spermatlds are a lso seen i n some o f the lumina of

the tubule. I n t e r s t i t l u m i s prominent. ( F i g 36)

W- g i t u i t a r x e x t r a c t l n winter froas Table 16 F i g 37

A significant ( P C 0.0Cl5) reduct ion was noted I n the

t e s t l c u l a r welght of the experrmental anlmals. The I n j e c t i o n o f

pituitary e x t r a c t caused precocious onset o f spermatogenesis.

411 the spermatogenetlc stages I n e,:perlmental animals showed

xncrease over those o f the con t ro l anlmals I P .: 0.05). The c e l l

nests of stage I V were hlgher (2.855r.1771) than other type of

c e l l nests. The i n j e c t i o n of p x t u i t a r y e x t r a c t moreover caused

strong spermratlon react lnn: on ly lmmature spermatoror

irregularly grouped were l e f t ~n the test15 tubules.

Summer p l t u & t a r y e v t r a c t ~n Winter f rogs Table 16 F l g 38

I n the erperlmental group a l l the stages showed r

s l g n i f l c a n t ( P 8 0.05) lncrease I n comparison t o the con t ro l s .

There 1s a reduction I n the t e s t r c u l a r welght l n comparison w l t h

con t ro l groups have been not iced. The spermatogenetic

a t l m u l a t ~ o n r n winter f rogs due t o summer p l t u l t a r y e x t r a c t was

r e l a t i v e l y higher than t h a t o f winter p l t u l t a r y e x t r a c t

adminis t rat ion.

Sumlnar fLqp p i l r a l l e l c s n t r p l Table 16 F i g 39

Frogs co l l ec ted dur ing summer months ( F i r s t f o r t n i g h t of

O p r i l ) served as c o n t r o l f r o g f o r summer season. A q u a n t i t a t i v e

h i s t o l o g i c a l study revealed tha t the seminiferous tubules a re

f l l l e d w i t h a l l the spermatogenetic c e l l nests i n good numbers.

Fresence of primary and secondary spermatogonia are prominent i n

the lumina of the tubule. I n t e r s t l t i u m has a c t i v e c e l l s .

p l t u l t a r v e x t r a c t I n summer f roas Table 16 F i g 40

There 1s a s i g n l f l c a n t (P 0.1) dec l l ne I n the t c s t i c u l a r

wplght of t reated anlmals as compared t o the con t ro l s . There 1s

an o v e r a l l accelerat ion o f spermatogenetlc stages I n the t rea ted

specimens. I n ~ n j e c t e d f rogs, the secondary spermatocytes

(3.5505.1495) showed a s l g n l f l c a n t (P 0.05) Increase than

con t ro l s (7.100+0.1565). The spermlatlon a c t l v l t y due t o t h l s

~ n j e c t l o n was a lso q u l t e ev ldent . The t e s t l c u l a r lumlna were

almost Jevold of spermatozoa I n the erperlmental i n d l v l d u a l s than

the normal.

Summer p i t u i t a r y e x t r a c t i n summer f roas Table 16 F i g 4 1

Increase I n the t e s t l c u l a r weight compared t o the con t ro l s

1s ev ident i n t h l s experiment. I n the t rea ted group a l l the

stages show a s t a t i s t i c a l l y significant (P i 0.005) increase than

I n the normal c o n t r o l anlmals. The count of secondary

spermatogonla (Stages 1 , I I ) and primary and secondary

spermatocytes are p a r t i c u l a r l y very h igh as compared t o the

con t ro l . Primary spormatogonia a r t a l so increased s ~ g n i f ~ c a n t l y

(P < 0.1) i n t h i s treatment.

Resul ts of 'Ana lys i s of Variance whlch arm adumbrated i n

Table 17 show s i g n i f i c a n t (P 0.001) v a r i a t i o n i n var ious

spermatogenetic stages dur ing d i f f e r e n t seasons o f the year.

S im i la r l y , the i n t e r a c t i o n between stages and treatment i s a l so

s i g n i f i c a n t (P < 0.001).

Discussion

I t has been establ ished experimental ly t h a t p i t u i t a r y

gonadotropin content va r ies dur ing the different seasons i n f r o g

R- temooraria. (Van Oordt, 1956) and t h i s accounts f o r i t s

discontinuous type o f spermatogenesls. I n another species o f

f rog R m hexadactvla, ehh ib i t i ng continuous type of

spermatogenesls, the re i s seasonal f l u c t u a t l o n i n the hypophyseal

gonadotropin secret ion (Casinathan e t d., 1977).

Srivastava e t d., (1984, 1986) have a lso reported, such a

seasonal f l u c t u a t l o n I n hypophyseal gonadotropin sec re t ion i n a

f rog R m tsar ina, which i s having a potentially continuous type

o f spermatogenesis. I n Rana tem~ora r ia , treatment of i n t a c t o r

hypophysectomised f rogs w i t h amphibian pituitary e , t rac ts show

tha t there i s seasonal v a r i a t i o n l n the t e s t i c u l a r response due

t o changes i n the s e n s i t i v i t y o f the germlnal epithelium t o

p i t u i t a r y ev t rac ts (Van Dordt, 1955). Thus, when p i t u i t a r y

e r t r a c t s obtalned from wlnter f rogs are i n j e c t e d i n t o f rogs

dur ing the r e s t i n g per iod and again a t the s t a r t of the

spermatogenetic cycle, the same amount o f e x t r a c t s t imu la tes 1

much greater spermatogenetic a c t i v l t y i n the l a t t e r groups than

i t does i n the winter frogs (Van Oordt e2 &., 1951) . When the

ehperlment was conducted by tak ing summer p i t u i t a r y ex t rac t ,

greater sensi txvxty was observed I n the f rogs (Van Oordt & a., 1952). 4 f l u c t u a t i o n I n the s e n s i t l v l t y has a l so been noted i n

the germinal ep l the l rum of R a n a esculenta, e v h i b i t i n g potentially

continuous type of spermatogenesis (Mialhe-Voloss, 1956) and I n

hypOphyseCtomlSed R- PlDiens by using p u r l f l e d mammallan

gonadotroprns (Basu and Nandi, 1965). Hut, I n t h i s l a t t e r

specles the greater s e n s i t i v i t y was observed I n winter f rogs.

basmathan and Rasu (1974) have recorded s i m l l a r observations i n

a t r o p i c a l f r o g R- heradactvla. I n the present study, w l t h the

f rog U~erodon svstoma, a t r o p l c a l species, the number o f

d ~ f f e r e n t spermatogenetlc c e l l nests va r ies considerably dur ing

the d i f f e r e n t months o f the year w l t h almost a complete absence

of hlgher spermatogenetic stages i n h a l f of the year. These

observed f a c t s lead us t o i n f e r tha t there mlght be seasonal

f l uc tua t ion I n hypuphyseal gonadotropin secret ion i n t h l s 6peClPS

of f rog a lso.

I t i s ev ident from the present study tha t admln iet rat ion of

pituitary e r t r a c t s obtained from winter f rogs has a comparatively

lower s t imu la to ry e f f e c t on the spermatogenesis both i n the

winter and summer frogs, whereas the administration o f p i t u i t a r y

e, t racts obtalned dur lng summer months e l i c i t s augmentation o f

a l l the spermatogenetic stages i n the winter f rogs as compared t o

the e f f e c t of winter pituitary e v t r a c t admin1strat lon on wlnter

frogs. I t ham bean e a r l i e r observed i n f r o g R m tan.orlri.

( S l u i t e r gt d., 1950) i n R m hexadactvla (Kasinathan and Bacu.

1972) and i n R&r& f r o r i n a (Sr ivastava e> &., 1984; 1986) t h a t

the spermatogenesis may be accelerated dur ing summrr months by

the a d m i n i s t r a t i ~ n of p i t u i t a r y ex t rac ts co l l ec ted dur ing the

winter season and the present i nves t iga t ion i n a t r o p i c a l f r o g

U~erodon svstoma confirms these e a r l i e r frndlngs.

The w in te r p i t u i t a r y e x t r a c t admin is t rat ion i n w in te r f rogs

r e s u l t s i n the increase o f on ly secondary spermatogonia (stages

1 , I I ) whereas the same e x t r a c t when administered i n t o the summer

f rogs r e s u l t s i n the augmentation of a l l stages I,II,III and IV.

The present observations i n Uaerodon svstoma corroborate the

e a r l i e r f i nd ings of Van Oordt (1960) I n R m t e m ~ o r a r l a ,

kasinathan and Basu (1972) I n R- he>adactvla and (Sr ivastava et

g . , 1984, 1986) i n Rana t i s r l n a . The ehogenous admin is t ra t ion

o f summer p i t u i t a r y ex t rac ts on summer and wlnter frogs r e s u l t i n

s t a t l s t t c a l l y s i g n i f i c a n t increase o f a l l spermatogenetic stages

as compared t o the winter p i t u i t a r y e > t r a c t administration on

winter and summer frogs. Eventhough the wlnter p i t u i t a r y e x t r a c t

a d m l n ~ s t r a t l o n on summer and wlnter f rogs r e s u l t I n statistically

s i g n l f l c a n t increase of a l l spermatogenetic stages as compared t o

the wlnter p i t u i t a r y e x t r a c t admin is t rat ion on wlnter and summer

frogs. Eventhough the winter p l t u l t a r y e x t r a c t admin is t ra t ion on

summer and w in te r f rogs enhances the spermatogenctic c e l l nests

when compared t o the normal c o n t r o l o f t h a t season i t i s always

less than t h a t of summer p i t u i t a r y e x t r a c t admin is t rat ion.

I t i s fu r the r ev ident by experimental data t h a t the e f f e c t

of summer p i t u i t a r y e x t r a c t admin is t rat ion on summer f rogs shows

a s t a t i s t i c a l l y s i g n i f i c a n t increase o f a l l spermatogmetic

stages a5 compared t o the e f f c c t o f summer p i t u i t a r y e x t r a c t

admin is t rat ion on the spermatogenetic process o f w in te r f rogs

where on ly secondary spermatogonia I and 11 are enhanced by t h i s

treatment.

S im i la r l y , the e f f e c t of winter p i t u i t a r y e x t r a c t on the

spermatogenetic c e l l nests of summer and winter f rogs shows a

s t a t l s t l c a l l y s i g n i f i c a n t l eve ls of d i f ference. It i s ev ident by

analys is of variance t h a t there i s s i g n i f i c a n t (PsO.OO1) l e v e l of

d i f f e rence i n the d i f f e r e n t spermatogenetic c e l l nests. Fur ther

~t i s a l so c l e a r t h a t both winter and summer pituitary e ) t r a c t s

e l i c l t m i t o t i c p r o l l f e r a t l o n o f secondary spermatogonial c e l l s

but summer p i t u i t a r y ea t rac t has got more pronounced e f f e c t as

compared t o wlnter p i t u i t a r y e , t rac t I n e l ~ c ~ t i n g t h i s response.

L i iewise, summer p r t u i t a r y ep t rac t has got more s t imu la t ing

e f f e c t on the d l v l s l o n s of primary spermatocytes i n winter f rogs

as compared t o winter p i t u i t a r y e , t rac t admin is t rat ion. With

regard t o secondary spermatocytic c e l l nests l t has been observed

tha t summer p i t u i t a r y e x t r a c t has got more pronounced e f f e c t on

the d i v i s i o n of secondary spermatocytes. These observations seem

t o l n d i c a t e tha t summer pituitary e r t r a c t i s more potent and

effective than t h a t of winter p i t u i t a r y ex t rac ts . The

spermatogenetic a c t i v l t y o f UDerodon svstoma i s considerably

hrgher dur ing summer months of the year whereas i t i s moderate

dur ing w in te r nuontha. So, i t may be assumed t h a t the s e n s i t i v i t y

of g~rmin-s l ep i the l ium dur ing summer months i s considmrably

h igher as compared t o winter months. This may a lso be ascribed

t o low sensitivity of the rpermatogonia t o the gonadotropic

hormones.

I t has been observed t h a t the summer p i t u i t a r y e ~ t r a c t

admin is t rat ion on summer and winter f rogs r e s u l t s i n the

statistically s i g n i f i c a n t ( P . 0.05; P 0.1) lncrcase i n the

r e l a t i v e t e s t l c u l a r welght. On the other hand, wlnter p i t u i t a r y

e > t r a c t admin ls t ra t lon t o summer and u l n t e r f rogs remul t i n

decrease I n the r e l a t i v e t e s t l c u l a r welght. The t e s t l c u l a r

weight reduct ion mlght be due t o the spermlation which r e s u l t s I n

the evacuation of spermatozoa from the seminiferous tubules.

Thls observation i s we l l j u s t l f l e d and confirms the previous

f l nd ings o f Van Oordt (1960) I n Rana temporarla.

I n the present er perlments, the e> treme spermatogenetlc

s t imu la t ion 1s noted from the summer p i t u i t a r y e x t r a c t

a d m ~ n i s t r a t l o n I n summer frogs. On the other hand no d i f fe rence

was observed between the spermlatlon react ion i n w ln te r and i n

spr ing frogs. I t may we l l be presumed that dur ing summer season

the hypoph~seal gonadotropin content and the s e n s i t i v i t y o f the

germinal epithelium are perhaps highest i n U~erodon svstoma

e , h i b i t l n g continuo-discontlnuos type o f spermatogenesis. Thls

observation i s i n consonance with e a r l i e r theory t h a t

gonadotropin secret lon of the hypophysls depends on the external

environmental condl t lons. The l a t t e r r n t u r n sens i t i zes the

seminiferous epi the l ium alone i n conjunct ion w i t h thc i n t e r n a l

phys io log ica l rhythm. However, i n t h i s p i c t u r e o f i n t e g r a t i o n o f

the d i f f e r e n t external and i n t e r n a l f a c t o r s r e l a t e d t o

spermatogenesis, there are several unsolved po in ts htwmen the

t a r g e t organ and the basic impact which needs greater

c l a r i f i c a t i o n through fu r the r experimental i nves t iga t ions .

Summarx

The study comprises of the e f fec ts o f exogenous

admln ls t ra t ion of p i t u i t a r y ex t rac ts obtained from d i f f e r e n t

seasons o f the year on spermatogenesis. Pituitary e x t r a c t s made

dur lng summer and wlnter months have been adminrstered

exogenously t o f rogs o f summer and winter months and Vice versa.

The injection o f summer and winter pituitary ex t rac ts both

when administered I n wlnter f rogs enhances the number of

secondary spermatogonlal and prlmary spermatocytic cys ts

s l g n l f i c a n t l y but the e f f e c t s are more pronounced w i t h summer

pituitary e x t r a c t . Similarly, the cy to loq lc divisions o f

spermatogonial and spermatocytlc cys ts are augmented fo l lowxng

any o f these e x t r a c t treatments but summer pituitary e x t r a c t i s

more potent. The exogenous a d m ~ n i s t r a t ~ o n o f wlnter and summer

p l t u l t a r y ex t rac ts I n summer f rogs a l so Increase the number o f

a l l t e spermatogenetlc cys ts but summer p l t u ~ t a r y e x t r a c t

administration t o summer f rogs i s most e f fec t i ve .

based on the above observatlons, i t would appear t h a t the

semin~ferous epithelium sensitivity and the gonadotropin leve l

vary considerably according t o seasonal changes whlch suggests

t n a t the gonadotropin secretion of the hypophysis p a r t l y drpmds

on the external environmental conditions, the l a t t e r i n turn

apparantl y s e n r i t i z l n g the germinal epi thel ium alone or i n

conjunction w i th the i n t e r n a l phys~o lag ica l rhythm.

ttrct of plt~mtary extract adminlstratlon of different =easons

, the spermatogenesis of U ~ e r o d o n s y e m a

-----------------------------------------.-------------------------------

Spermatopenetlc stages Testlcular -rcctments ---------------------------------------.-- welqht , I i ! 1 1 1 I V ( s g i

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. . , q , L , , , , , - ..4,11 a . . '1 , 4 . i i i , , . , > - I 25.5, i r j , ,

. I . ! ? : < . , > . I , > ? ? , a . T.,,, , > . > p - , < , , ,?Q, I . , , > , , ! . , i f l l r t , a ! I r , * , r 1 e I I n ( b l l n ( e l i n

--- .---- -. .-----

I . , ),:)em I , = t o . * . a l L ' a l i l r s --i Meirr, + SEN

TABLE t i

-,,-, way inalysls of variance of d a t a fr,r s p e r m a t o q e n e t ~ c staijes

Jpcr~&_n ~ i l ; f u a p l t ~ l l t a r y e , : t r a c t a d r i n : s t r a t l o n dttr ln"

v - r r n t seasons of t h e v e s r

- S&tm nf square

c - Drqree of freedom

Hean Sqclare

LEGENDS FOR FIGURES

Fig.36. Section through the test15 of control frog of wlnter

season (Haemalum and eosin X45Cl)

Flg.57. Sectlon through the test15 of wlnter frog treated with

ulnter pituitary e) tracts. Numerous secondary

spermatogonla and spermlation actlon due to treatment

are evldent histologically. (Haemalum and eosin X450)

Fig.38. Sectlon through the testls of wlnter frog treated with

summer pituitary extracts. Note the well developed

condition of the secondary spermatogonla and primary

sprrmatocytes in the folllcle (Haemalum and eosln X450)

LEGENDS FDR FIGURES

Flg.39. Section through the t e s t l s o f c o n t r o l f r o g o f summsr

season. (Haemalum and eosin X450)

Flg.40. Section through the t e s t l s o f summer f rog treatmd w i t h

winter p l t u l t a r y ex t rac ts . Spermatogenesis I n general

l ess accelerated. (Haemalum and eosln X450)

Flg.41. Sectlon through the t e s t i s o f summer f rog t rea ted w l t h

summer p l t u l t a r y ex t rac ts . Note the o v e r a l l

accelerat ion o f the spermatogenetic stages due t o

treatment (Haemalum and eosin X450)

CONTROL

WPWF

SPWF

Spermatogenetlc stages

Fig. 42

Effect of Summsr and Winter pituitary extracts admin~stration on the Spermatogenesis of Winter Frog.

WPWF - Winter Pituitary extract injected on Winter Frog. SPWF - Summer Pituitary extract injected on Winter Frog.

128 b

CONTROL

WPSF

SPSF

Spermatogenetic stages

Fig. 43

Effect of Summer and Winter Pttu~tary extracts admlnistration on the Spermatogenes~s of Summer Frog.

WPSF - Winter pituitary extract injected In Summer Frog. SPSF - Summer pituitary extract injected In Summer Frog.