252 



HYPOPHYSIS AND GOXADOTROPHIC HORMONES 



2. Fish 



Fish have been reported to respond to 

 gonadotrophins of piscine origin (Hasler, 

 Meyer and Field, 1939; Rasquin, 1951; 

 Hisaw and Albert, 1955; Hoar, 1955; Ram- 

 aswami and Simdararaj, 1956, 1957) by 

 exhibiting out-of-season oocyte growth and 

 spawning. It is to be noted, however, that 

 satisfactory control experiments are often 

 lacking. Fish respond less readily to am- 

 i:)liibian pituitary. Induced spawning in 

 rainbow trout (Migita, Matsomoto, Kino- 

 chita, Sasaki and Ashikawa, 1952) and cat- 

 fish (Ramaswami and Sundararaj, 1957) 

 has been claimed to follow the injection of 

 frog pituitary. Fish appear to be almost 

 totally insensitive to gonadotrophins of 

 avian and mammalian origin (de Azevedo 

 and Canale, 1938; Hasler, Meyer and Field, 

 1939; Hoar, 1955); however, Dodd (1955) 

 calls attention to some instances of doubt- 

 ful or limited effectiveness of mammalian 

 gonadotrophins, especially human urinary 

 gonadotrophins, in fish. Pickford and Atz 

 (1957) brought together the varied and con- 

 flicting results of the multitudinous studies 

 of reproductive physiology in fish. 



3. Amphibians 



Amphibians are notably responsive to 

 gonadotrophins from widely differing phy- 

 logenetic sources, yet even among some of 

 the anura the gonadotrophins show a high 

 degree of species specificity (Greaser and 

 Gorbman, 1939; Houssay, 1954). The ef- 

 fectiveness of homoplastic anuran pitui- 

 taries in inducing spermiation, ovulation, 

 and oviposition has become a part of classi- 

 cal biology. By contrast, the induction of 

 ovulation in Rana temporaria requires 150 

 times as much beef as Rana pituitary (Gal- 

 lien, 1955a), and Houssay has shown that 

 the South American toad, Bufo arenarum, 

 is less sensitive to rat and human hypophy- 

 sis than to pituitaries of anuran origin. 

 Strangely, the anura, although generally 

 responsive to mammalian gonadotrophins of 

 pituitary or placental origin, have reacted 

 poorly— if at all — to injected brei of elasmo- 

 branch pituitaries (Greaser and Gorbman, 

 1939) or to those of telcosts (Greaser and 

 Gorbman, 1939; Atz and Pickford, 1954). 



Pursuing the matter of phyletic considera- 

 tions further, Atz and Pickford (1954) re- 

 port that the Russian workers, Stroganov 

 and Alpatov (1951) found frogs more sensi- 

 tive than fish to sturgeon pituitary; and 

 interestingly, although their data are mea- 

 ger, Wills, 'Riley and Stubbs (1933) ob- 

 tained ovulation in Bujo americanus and 

 Rana pipiens with gar pike hypophyses. The 

 sturgeon and gar pike, as Greaser and Gorb- 

 man (1939) point out, are closer in the 

 phyletic scale to the amphibia than they are 

 to the fish whose pituitaries were ineffective 

 in amphibia. 



Some exploratory studies have been made 

 of the action of mammalian FSH and LH 

 in amphibia. The male toad, Bnfo melanos- 

 tictus, responded to mammalian FSH and 

 LH (Bhaduri, 1951), whereas Bujo bufo 

 responded negatively to FSH (Thorborg 

 and Hansen, 1950). Greze (1949) reported 

 that LH produced a positive spermiation 

 test in Rana esculanta, and Atz and Pick- 

 ford (1954) , after testing a number of mam- 

 malian pituitary preparations, concluded 

 that LH was 40 to 100 times more active 

 than FSH in causing sperm release in Rana 

 pipiens; the positive responses obtained 

 with FSH were easily attributable to an 

 LH contaminant. Wright and Hisaw (1946) 

 studied the response of frog ovaries to puri- 

 fied mammalian gonadotrophins and found 

 that, although FSH ovulated the intact 

 frog, it was not effective in hypophysecto- 

 mized females. Using the technique of Heil- 

 brunn, Dougherty and Wilbur (1939), 

 Wright and Hisaw applied sheep FSH to 

 frog ovaries in vitro and failed to induce 

 ovulation; but by combining FSH and LH 

 in an appropriate ratio, ovulation was ob- 

 tained. They believe that the principal 

 function of FSH in the frog is to render the 

 ovary sensitive to an ovulating stimulus. 

 OA'iposition was induced in the salamander, 

 Triturus viridescens, by LH but not by FSH 

 (Mayo, 1937) and Witschi (1937) elicited 

 ovulation in the newt, Taricha torosa, with 

 beef and turkey hypophyses but not with 

 pregnant mare's serum (PMS) gonado- 

 trophin. 



The sensitivity of ami)hibians to human 

 pituitary and chorionic gonadotrophins has 

 rendered tliem extremely useful in clinical 



