3. FISH PROLACTIN AND GROWTH HORMONE
231
tary (Olivereau and Chartier-Baraduc, 1966; Olivereau, 1967). It should
be noted that pig GH has. no sodium-conserving activity in P. latipinnu
(Ball and Ensor, 1967), and beef GH did not promote tolerance of freshwater in hypophysectomized killifish (Burden, 1956; Pickford et ul.,
1965 ) .
Like prolactin (Section I ) , GH induced weight increase and stimulated secretory activity in the androgen-primed seminal vesicles of the
hypophysectomized Indian catfish, Heteropneustes fossilis ( Sundararaj
and Goswami, 1965), and synergized with androgen and prolactin to produce a maximal response. This recalls the well-documented ability of GH
to potentiate the tropic effects of gonadotropins and androgens on the
testis and accessary structures in mammals (see Woods and Simpson,
Porcine GH slightly elevated the depressed thrombocyte count of
hypophysectomized P . latipinnu without affecting any of the other blood
elements ( Ball et al., 1966a). In hypophysectomized F . heteroclitus, GH
had no action on any hematological parameter ( Slicher, 1961).
1961).
F. Effects of Fish Pituitary Material on Growth in Other Vertebrates
Although hypophysectomized killash respond with linear growth to
GH from pig, beef, sheep, monkey, and man ( Pickford, 1959; Pickford
et al., 1959; Geschwind, 1967), teleostean pituitary material will not promote growth in the rat (Pickford, 1957; Solomon and Creep, 1959;
Moudgal and Li, 1961) or in the tadpole of Ram temporuriu (Enemar
and von Mecklenburg, 1962). It has been suggested that induction of
growth in Rana temporaria tadpoles is an indicator of prolactin rather
than of GH (Bern et al., 1967), but according to Enemar (1967) tadpoles
of the size used in his laboratory respond to GH but not to prolactin.
Cyclostome pituitary material is also without action on tadpole growth
( Enemar and von Mecklenburg, 1962). Furthermore, crystalline fish GH,
active in F . heteroclitus ( Pickford, 1954a), is without effect on growth in
hypophysectomized rats ( Wilhelmi, 1955). However, Geschwind ( 1967)
has recently reported that the pituitary of the lungfish, Protopterm
aethiopicus, showed good growth-promoting activity in the rat, but that
glands from the dogfish, Squalus, were inactive. Once again, the dipnoan
allies itself with tetrapods rather than with other fishes (cf. Section I, A ) .
These data presumably indicate differences in the molecular structure of
fish and tetrapod GH, about which regrettably little is known
( Geschwind, 1967).
231
tary (Olivereau and Chartier-Baraduc, 1966; Olivereau, 1967). It should
be noted that pig GH has. no sodium-conserving activity in P. latipinnu
(Ball and Ensor, 1967), and beef GH did not promote tolerance of freshwater in hypophysectomized killifish (Burden, 1956; Pickford et ul.,
1965 ) .
Like prolactin (Section I ) , GH induced weight increase and stimulated secretory activity in the androgen-primed seminal vesicles of the
hypophysectomized Indian catfish, Heteropneustes fossilis ( Sundararaj
and Goswami, 1965), and synergized with androgen and prolactin to produce a maximal response. This recalls the well-documented ability of GH
to potentiate the tropic effects of gonadotropins and androgens on the
testis and accessary structures in mammals (see Woods and Simpson,
Porcine GH slightly elevated the depressed thrombocyte count of
hypophysectomized P . latipinnu without affecting any of the other blood
elements ( Ball et al., 1966a). In hypophysectomized F . heteroclitus, GH
had no action on any hematological parameter ( Slicher, 1961).
1961).
F. Effects of Fish Pituitary Material on Growth in Other Vertebrates
Although hypophysectomized killash respond with linear growth to
GH from pig, beef, sheep, monkey, and man ( Pickford, 1959; Pickford
et al., 1959; Geschwind, 1967), teleostean pituitary material will not promote growth in the rat (Pickford, 1957; Solomon and Creep, 1959;
Moudgal and Li, 1961) or in the tadpole of Ram temporuriu (Enemar
and von Mecklenburg, 1962). It has been suggested that induction of
growth in Rana temporaria tadpoles is an indicator of prolactin rather
than of GH (Bern et al., 1967), but according to Enemar (1967) tadpoles
of the size used in his laboratory respond to GH but not to prolactin.
Cyclostome pituitary material is also without action on tadpole growth
( Enemar and von Mecklenburg, 1962). Furthermore, crystalline fish GH,
active in F . heteroclitus ( Pickford, 1954a), is without effect on growth in
hypophysectomized rats ( Wilhelmi, 1955). However, Geschwind ( 1967)
has recently reported that the pituitary of the lungfish, Protopterm
aethiopicus, showed good growth-promoting activity in the rat, but that
glands from the dogfish, Squalus, were inactive. Once again, the dipnoan
allies itself with tetrapods rather than with other fishes (cf. Section I, A ) .
These data presumably indicate differences in the molecular structure of
fish and tetrapod GH, about which regrettably little is known
( Geschwind, 1967).