276
AUGUST EPPLE
(1895) and Laguesse ( 1895) had shown that the Brockmann bodies contain the equivalent of the endocrine pancreas of other vertebrates,
Massari (1898) demonstrated the existence of two different types of islet
cells in teleosts. It was again in teleosts, where Bowie (1925) fkst
described a third granular type of islet cell.
Using extracts from Brockmann bodies, in 1904 Diamare and Kuliabko
tried to study the role of the endocrine pancreas in carbohydrate metabolism. At the same time, Rennie even treated human patients with preparations from fish islets ( Rennie and Fraser, 1907).
After the discovery of insulin, Macleod (1922) demonstrated its islet
origin by a comparison of the glycemic effects of extracts from Brockmann
bodies and zymogen tissue. This was seemingly codinned by the observation that removal of the Brockmann bodies is followed by a long-lasting
hyperglycemia ( McCormick and Macleod, 1925; cf. Macleod, 1926;
Simpson, 1926).
McCormick ( 1924) and McCormick and Noble ( 1925) also considered
the commercial production of insulin from Brockmann bodies. In 1929,
Jensen and co-workers achieved a preparation of crystalline fish insulin.
But at this time, advanced extraction techniques for mammalian pancreas
made it unnecessary to prepare fish insulin for therapeutic purposes. After
the second world war, again this possibility was considered in Germany
(Zeile, 1948; Roy, 1957); and in Japan insulin from teleosts was used
clinically (Yamamoto et al., 1960).
In recent years, fish insulins became important in the research on
biological and immunological hormone specificities (cf. S. Wilson, 1966;
Falkmer and Wilson, 1967), and Yalow and Berson (1964) discussed the
use of fish insulin in diabetics with immunological resistance to mammalian preparations.
Various investigators also took advantage of the Brockmann bodies
in studies on the biosynthesis of insulin (cf. Lazarow et al., 1964a;
Lazarow, 1965). However, the use of mammalian islets may become more
common, owing to improved microdissection techniques ( Hellerstrijm,
1964; Moskalewski, 1965; Lacy and Kostianovsky, 1967). Nevertheless,
the Brockmann bodies might well become important in future studies on
still unknown islet hormones (see Section 11, D) .
There is an increasing evidence that the functions of islet hormones
in fishes differ to some extent from those in mammals. This opens the
possibility that we might learn by studying fishes more about the functions
of the islet hormones which are less obvious in higher vertebrates.
Furthermore, the apparently high species specificity of glucagon, and its
common origin with secretin (cf. Weinstein, 1968) certainly will prompt
studies on the evolution and functions of this hormone in fishes.
AUGUST EPPLE
(1895) and Laguesse ( 1895) had shown that the Brockmann bodies contain the equivalent of the endocrine pancreas of other vertebrates,
Massari (1898) demonstrated the existence of two different types of islet
cells in teleosts. It was again in teleosts, where Bowie (1925) fkst
described a third granular type of islet cell.
Using extracts from Brockmann bodies, in 1904 Diamare and Kuliabko
tried to study the role of the endocrine pancreas in carbohydrate metabolism. At the same time, Rennie even treated human patients with preparations from fish islets ( Rennie and Fraser, 1907).
After the discovery of insulin, Macleod (1922) demonstrated its islet
origin by a comparison of the glycemic effects of extracts from Brockmann
bodies and zymogen tissue. This was seemingly codinned by the observation that removal of the Brockmann bodies is followed by a long-lasting
hyperglycemia ( McCormick and Macleod, 1925; cf. Macleod, 1926;
Simpson, 1926).
McCormick ( 1924) and McCormick and Noble ( 1925) also considered
the commercial production of insulin from Brockmann bodies. In 1929,
Jensen and co-workers achieved a preparation of crystalline fish insulin.
But at this time, advanced extraction techniques for mammalian pancreas
made it unnecessary to prepare fish insulin for therapeutic purposes. After
the second world war, again this possibility was considered in Germany
(Zeile, 1948; Roy, 1957); and in Japan insulin from teleosts was used
clinically (Yamamoto et al., 1960).
In recent years, fish insulins became important in the research on
biological and immunological hormone specificities (cf. S. Wilson, 1966;
Falkmer and Wilson, 1967), and Yalow and Berson (1964) discussed the
use of fish insulin in diabetics with immunological resistance to mammalian preparations.
Various investigators also took advantage of the Brockmann bodies
in studies on the biosynthesis of insulin (cf. Lazarow et al., 1964a;
Lazarow, 1965). However, the use of mammalian islets may become more
common, owing to improved microdissection techniques ( Hellerstrijm,
1964; Moskalewski, 1965; Lacy and Kostianovsky, 1967). Nevertheless,
the Brockmann bodies might well become important in future studies on
still unknown islet hormones (see Section 11, D) .
There is an increasing evidence that the functions of islet hormones
in fishes differ to some extent from those in mammals. This opens the
possibility that we might learn by studying fishes more about the functions
of the islet hormones which are less obvious in higher vertebrates.
Furthermore, the apparently high species specificity of glucagon, and its
common origin with secretin (cf. Weinstein, 1968) certainly will prompt
studies on the evolution and functions of this hormone in fishes.