By Priv. Doz. Dr. Klaus Tiedemann (auth.)
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Additional info for The Mesonephros of Cat and Sheep: Comparative Morphological and Histochemical Studies
Bargmann (1937) regards similar protrusions in fish as being connected with the formation of urinary colloids. The therm "apocrine secretion ", which is used in many of these papers, is inappropriate here. , 1961; Montagna, 1962; Biempica and Montes, 1965; Munger, 1965 a,b). Although apocrine processes are described in which no secretions can be distinguished electron microscopically (Svajger, 1968), the term "apocrine secretion" is always connected somehow with the presence of specific secretions; it should not be used for the mesonephric protrusions, as it is not clear, whether they actually contain elaborated secretions.
In the rabbit, which also has apical cytoplasmic protruSions (Ernst, 1926; Molchanova, 1972), the electron microscopical results by Leeson (1957, 1959, 1960) give no indication of these formations, apart from the flgure of a badly fJXed apical pole. They have not been mentioned in the chicken (Gibley and Chang, 1967) either, although they have been shown by the light microscope (Nicolas, 1891; Wendler, 1965). 55 In the literature on the light microscopy of the mesonephros the cytoplasmic protrusions have been dealt with, and misinterpretated, many times, so that only a choice of opinions can be discussed here.
Lipid droplets are sparse and small (Fig. 23). The collecting tubule which largely resembles the distal tubule undergoes only a few alterations with advanCing maturity. Its ultrastructure resembles the picture of the 18th day in the distal tubule. Wolffian Duct The Wolffian duct has been investigated in the middle part of the mesonephros exclusively. The cuboidal cells largely resemble those of the collecting tubule (comp. Fig. 23 with Fig. 24) so that a detailed description is unnecessary. There are only few age-dependent alterations; they concern the presence of glycogen in the first place.