34
J. N. BALL AND BRIDGET I. BAKER
derived from these, with larger granules (up to 180 mp), and with big
empty vesicles and an active type of endoplasmic reticulum. In the trout,
Follenius (1963a) described a cell type, probably a gonadotrop, which
contained numerous granules of various sizes and showed extreme development of the endoplasmic reticulum in the form of smooth-walled
vesicles. At certain stages of the activity cycle very large vacuoles appear
in these cells.
From what has been written so far, the main tinctorial properties of
the gonadotrops will be obvious. It is particularly interesting that PbH
is so useful in distinguishing two types of gonadotrops, particularly when
used in combination with PAS (Table I and Fig. 16). This technique has
also been valuable in study of the pars intermedia (Section 11, B, 6)
and ACTH cells (Section 11, B, 2), and it also has been used to separate
two gonadotrops in mammals (Carlon, 1966, 1967; see discussion in
Olivereau, 1967a, p. 303). More definitely histochemical investigations
have been performed. Olivereau and Fontaine (1966) summarized their
histochemical data on these cells in the mature eel: The PAS reaction
indicates the presence of neutral glycoproteins, while the staining of the
granules with Ox-AB at low pH (0.2) indicates their content of acid
mucopolysaccharides, which is rather feeble however ( Olivereau, 1967a).
The acidic nature of the gonadotrop granules is also indicated by their
reactions with Gabe’s AF after permanganic oxidation, md by their slight
afEnity for orange G in PAS-OG. In addition to these specific glycoproteinaceous secretory granules, the eel gonadotrops when mature also
contain very large granules with variable tinctorial affinities (OG + ve,
erythrosin + ve, PAS + ve, BA + ve, A F + ve, Aniline blue + ve),
which may be lysosomes ( Olivereau, 1967a). Similar putative lysosomes
occur in mature gonadotrops in Poecilia (see below).
Olivereau (1962c, 1963b) found that eel gonadotrops are rich in
SS/SH groups, a property they share with gonadotrops in other
teleosts (Matty and Matty, 1959). In both the goldfish and Poecilia
sphenops, the gonadotrops, and probably also the TSH cells (PAS + ve
and AB + ve cells), incorporated s5S more rapidly than other cell types,
probably forming sulfate esters of acid mucopolysaccharides ( Deminatti,
1963, 1964b); but in the goldfish the gonadotrops only feebly incorporated labeled amino acids ( Deminatti, 1962a,b ) , According to Leray
(1966) the gonadotrops in Mugil cephalus display only minor content of
SS/SH groups, in contrast to other fishes. The same author (Leray,
1965) reported that carp gonadotrops are rich in sialic acid and that the
pituitary content of sialic acid increases with sexual maturation and falls
after spawning. Sialic acid is a constituent of mammalian gonadotropins
and TSH (Butt, 1967), and can be demonstrated histochemically in both
the TSH and FSH cells of the cat (Racadot, 1963b).
J. N. BALL AND BRIDGET I. BAKER
derived from these, with larger granules (up to 180 mp), and with big
empty vesicles and an active type of endoplasmic reticulum. In the trout,
Follenius (1963a) described a cell type, probably a gonadotrop, which
contained numerous granules of various sizes and showed extreme development of the endoplasmic reticulum in the form of smooth-walled
vesicles. At certain stages of the activity cycle very large vacuoles appear
in these cells.
From what has been written so far, the main tinctorial properties of
the gonadotrops will be obvious. It is particularly interesting that PbH
is so useful in distinguishing two types of gonadotrops, particularly when
used in combination with PAS (Table I and Fig. 16). This technique has
also been valuable in study of the pars intermedia (Section 11, B, 6)
and ACTH cells (Section 11, B, 2), and it also has been used to separate
two gonadotrops in mammals (Carlon, 1966, 1967; see discussion in
Olivereau, 1967a, p. 303). More definitely histochemical investigations
have been performed. Olivereau and Fontaine (1966) summarized their
histochemical data on these cells in the mature eel: The PAS reaction
indicates the presence of neutral glycoproteins, while the staining of the
granules with Ox-AB at low pH (0.2) indicates their content of acid
mucopolysaccharides, which is rather feeble however ( Olivereau, 1967a).
The acidic nature of the gonadotrop granules is also indicated by their
reactions with Gabe’s AF after permanganic oxidation, md by their slight
afEnity for orange G in PAS-OG. In addition to these specific glycoproteinaceous secretory granules, the eel gonadotrops when mature also
contain very large granules with variable tinctorial affinities (OG + ve,
erythrosin + ve, PAS + ve, BA + ve, A F + ve, Aniline blue + ve),
which may be lysosomes ( Olivereau, 1967a). Similar putative lysosomes
occur in mature gonadotrops in Poecilia (see below).
Olivereau (1962c, 1963b) found that eel gonadotrops are rich in
SS/SH groups, a property they share with gonadotrops in other
teleosts (Matty and Matty, 1959). In both the goldfish and Poecilia
sphenops, the gonadotrops, and probably also the TSH cells (PAS + ve
and AB + ve cells), incorporated s5S more rapidly than other cell types,
probably forming sulfate esters of acid mucopolysaccharides ( Deminatti,
1963, 1964b); but in the goldfish the gonadotrops only feebly incorporated labeled amino acids ( Deminatti, 1962a,b ) , According to Leray
(1966) the gonadotrops in Mugil cephalus display only minor content of
SS/SH groups, in contrast to other fishes. The same author (Leray,
1965) reported that carp gonadotrops are rich in sialic acid and that the
pituitary content of sialic acid increases with sexual maturation and falls
after spawning. Sialic acid is a constituent of mammalian gonadotropins
and TSH (Butt, 1967), and can be demonstrated histochemically in both
the TSH and FSH cells of the cat (Racadot, 1963b).