A Macro-Anatomical Investigation of the Some Skull Bones of Nehring's Blind Mole Rats (Spalacidae: Nannospalax nehringi).

This study was aimed to demonstrate the specific anatomical features of the skull bones of Nehring's blind mole rats. Eight skulls, belonging to animals of both sexes, were used. The occipital squama contributed to the formation of the caudal portion of the skull roof. The foramen magnum was quite large. The external occipital crest was present only in the males. The parietal bones formed the middle portion of the skull roof together with the well-developed inter-parietal bones. The zygomatic process of the temporal bone formed the zygomatic arch by extending to the temporal process of the zygomatic bone. The zygomatic process of the frontal bone and the frontal process of the zygomatic bone laterally bordered the orbit. There was a single septal process of the nasal bone. Each ramus of the mandibula had four processes. The mandibular ramus had an angular process on its caudal rim, which extended dorsolaterally. The dorsal free end of the mandibular ramus possessed a coronoid process. In the back, there were two other processes, situated medially and laterally. The medially situated process was referred to as a condylar process, and the laterally situated process was referred to as an alveolar process. The alveolar process detected on the mandibular ramus has not been reported in any rodent species, other than those of the family Spalacidae. Blind mole rats can be a real eye-opener for evolutionary science. The burrowing rodents are key to answering a controversial question about how new species arise.

Morphological study by scanning electron microscopy of the lingual papillae in the Middle East blind mole rat (Spalax ehrenbergi, Nehring, 1898).

There is no definite information about the tongue morphology of blind mole rats owing to spreading of these animals to only a certain habitat. For this reason, we aimed to examine the morphological structure of the tongue by scanning electron microscopy (SEM) in this species. In this study, the tongues of four blind mole rats were used and the morphology of its lingual surface, different types of papillae, their characteristics and topographical distribution was described. Three types of papillae (filiform, fungiform and vallate) and lingual prominence were observed. The dorsal surface of the tongue was covered by filiform papilla; and filiform papillae demonstrated the most numerous type of lingual papilla. Fungiform papillae were rounded in shape and randomly distributed particularly on the anterior and medial region. In addition, each fairly convex fungiform papilla was surrounded by a continuous circular pad like a crown. The two oval vallate papillae were situated symmetrically on the posterior region and obliquely to the median line of the tongue. The body of vallate papillae was surrounded by a continuous trench and mucosal folds. The lingual prominence between medial and posterior region and a transversal groove just in front of it were observed. Furthermore, a limited tuber and root based diet and gnawing have together resulted in similarity of the tongue of the rodent, giving it some characteristics typical of a herbivore and an insectivore.

Effects of tamoxifen administration in rat vaginas: an ultrastructural and light microscopy study.

BACKGROUND: Tamoxifen (TAM) inhibits the initiation of carcinogen induced rat mammary tumours and is administrered for extended periods after the initiation of carcinogenesis. It is also a widely used treatment for breast and gynaecological cancer. OBJECTIVE: In this study, we aimed to investigate tamoxifen (TAM) administration on vagen development in rats. MATERIAL & METHODS: Twenty sexually mature and pregnant Wistar albino rats were chosen as the animal model. They were divided into two groups. Group I: Control group, Group II: Tamoxifen applied (between gestational day 16 and 21 days); 100 microg tamoxifen citrate (TAM) in 0.05 ml saline subcutaneously per day/animal. After birth, all female rats were sacrificed on the 60th day and were taken vaginal tissue. Transmission electron microscopy and light microscopy have been used to study changes to the vaginal epithelium. RESULTS: A statistically significant reduction of birth body weight was noted in the experimental group of rats when compared to the control group (P < 0.05). We saw increase in the thickness of the epithelium layer and irregularity and disappearance of microscopic papilla, cytoplasmic vacuolation in cells of the surface layer, thin and irregular basal membrane, lateral junction of cells were destroyed in the TAM treated groups. In conclusion, neonatal tamoxifen administration affects vagina epithelium and lead to decreasing birth body weight and vaginal adenosis.

The effects of sialoadenectomy & flutamide on skin development.

BACKGROUND: Epidermal growth factor is a low molecular weight polypeptide with 53 amino acids and is known to stimulate cell proliferation and differentiation in a wide range of tissues. The submandibulary gland in the mouse is a rich source of epidermal growth factor and decreased plasma epidermal growth factor levels have been observed after sialoadenectomy (removal of the submandibular glands). Furthermore. there is evidence that epidermal growth factor stimulates spermatogenesis and reverses antiandrogen induced cryptorchidism. OBJECTIVE: In the present study, the teratogenic effects of sialoadenectomy and antiandrogen (flutamide) administration on rat skin were investigated histologically. MATERIALS & METHODS: Thirty Spraque-Dawley female rats were separated into three groups (n = 10), a control (sham-operated) and two experimental groups. The first experimental group of rats were subjected to sialoadenectomy in order to create maternal EGF deficiency one month before copulation. The second experimental group of rats were given flutamide (10 mg/100 g) for ten days during pregnancy. Three months after birth, a penile skin biopsy was taken from respective offspring in all groups. RESULTS: A statistically significant reduced body weight and length were noted in the first group of litters (maternal EGF deficient) and in the flutamide administered group when compared to the control group. Atrophic epidermis and dermal adnexa were observed histologically as the teratogenic effects of sialoadenectomy and flutamide administration on rat skin development. CONCLUSION: Epidermal growth factor is a key hormone for skin development and antiandrogen administration may insult this process by interfering with epidermal growth factor metabolism.