Nuclear and Cytoplasmic Inclusion Bodies in Pinealocytes of the Cotton Rat, Sigmodon hispidus: An Electron Microscopic Study

Abstract

Electron microscopic observations on pinealocytes of cotton rats (Sigmodon bispidus) killed in October revealed the presence of cytoplasmic inclusion bodies (CIBs) and two kinds of nuclear inclusions--coiled bodies and granular inclusion bodies. These inclusions were usually not bounded by a membrane. CIBs showed round or irregular profiles and consisted of granular and filamentous materials of moderate electron opacity intermingled with electron-lucent areas. Nuclear granular inclusions appeared as homogeneous or heterogeneous granules of variable electron opacity, which usually exhibited round profiles of variable diameters and consisted of granular and filamentous elements. Electron-opaque granules were observed in perinuclear spaces, dilated cisternae of rough endoplasmic reticulum, as well as in the central portion of CIBs. In CIBs containing granules, the peripheral region was composed of the moderately electron-opaque substance seen in usual CIBs, while the central core was occupied by a granular and filamentous substance and an intervening electron-lucent matrix. Since an electron-opaque granular substance in nuclei, perinuclear spaces, cisternae of rough endoplasmic reticulum, and the central portion of CIBs may occur concomitantly, the granules seen in these sites may be related. Coiled bodies were round in profile and were composed of electron-opaque strands consisting of granular and filamentous elements and intervening material of low electron opacity. This structure, frequently located in close proximity to the nuclear granular inclusions, may play a role in the formation of the intranuclear granules in cotton rat pinealocytes.

Effects of Long and Short Photoperiod on the Ultrastructure of Pinealocytes of the Cotton Rat (Sigmodon hispidus)

“…The ultrastructure of the cotton rat pinealocyte has been recently described in detail [Matsushima et al, 1979[Matsushima et al, , 1984Karasek et al, 1982;1983b,c). Therefore, here we include only a typical electron micrograph of that cell ( Fig.…”

Nucleolus-like bodies in the pineal gland of the adult yak (<i>Bos grunniens</i>)

“…In previous studies, NLBs have been described as an accumulation of fine flocculent material in the pineal gland and it was suggested that this contains 5-hydroxytryptamine (5-HT) (Machado et al 1968). However, Matsushima et al (1984) observed that inclusion bodies in pinealocytes of the cotton rat appeared to contain protein and calcium and may represent NLBs, mineral deposits, secretory products or viral inclusions. In a previous study on dogs (Calvo et al 1988), two types of granules in pinealocytes were identified ultrastructurally as melanin.…”

“…These inclusion bodies may represent nucleolus-like bodies (NLBs), mineral deposits, or secretory products (Karasek et al 1983), as well as cytoplasmic inclusion bodies (CIBs) and two kinds of nuclear inclusions, coiled bodies and granular inclusion bodies. These bodies, components of the germinal vesicles (Inoue et al 2011), are not usually bounded by a membrane (Matsushima et al 1984). They are defined as NLBs (Fechner 1986;Kleshchinov 1989;Takeuchi 1980).…”

Three structures associated with the nucleolus in male rat germinal cells: Round body, coiled body, and “nubecula” and general presence of round body at male meiosis

“…The coiled body was first described in somatic cells as a 300-nm- (Monneron and Bernhard, 1969) to 900-nm wide sphere (Seite et al, 1982) composed of units called "threads" (Monneron and Bernhard, 1969;Bernhard, 1971;Sananes and Le Goascogne, 19761, "strands" (Kinderman and LaVelle, 1976;Matsushima et al, 1984) and hereafter "coils" (Kinderman and LaVelle, 1976;Schultz, 1989). The coils had a width varying from 30 nm (Lafarga et al, 1983a1 to 63 nm (Hervas et al, 1980.…”