Bankole Olusiji Oke

Relationship between submandibular gland epidermal growth factor and spermatogenesis in C3H mice

Epidermal growth factor (EGF), a potent mitogen produced primarily in the submandibular gland of adult male mice, has been implicated in modulating processes known to be of vital importance in the regulation of spermatogenesis. In the present investigation we demonstrate that submandibular gland EGF from adult male mice is indeed capable of displacing radiolabeled EGF from testicular membranes. Scatchard analysis of this binding site reveals that it is of high affinity (Kd = 0.77 nM) and low capacity (Bmax = 8.15 fmol/mg protein). Cross-linking of 125I-EGF to the identical membrane preparation resulted in the SDS-PAGE/autoradiography identification of a single band at approximately 170 kDa. Next, we examined the cellular distribution of the EGF receptor in the testis using biotin-streptavidin immunoperoxidase and employing different antisera probes generated to a conserved sequence of the EGF receptor. The Scatchard and cross-linking data described above, along with the immunocytochemistry results, suggest strongly that there is only one functional binding site for EGF in the adult testis and that this receptor is present in Sertoli and Leydig cells.

Morphometric Investigation of the Brainof West African Dwarf Sheep in Nigeria

Se efectuo un estudio morfometrico en 20 encefalos frescos, congelados de ovejas enanas del Oeste africano. El peso promedio del cerebro fue de 69.14g, mientras que el largo y la altura fueron de 7.48cm y 4.17cm, respectivamente. La longitud promedio del cerebro y cerebelo de 5.08cm y 2.27cm, respectivamente. El peso relativo del encefalo fue 0,08%, mientras que el de la cabeza fue 0.8%. Hubo diferencias significativas (p< 0.05) en el peso de la cabeza, del encefalo, longitud y altura del cerebro y en el peso relativo del cerebro de los animales de mas de 10kg, si estos son comparados con animales de menor peso. Los valores de los primeros cuatro parametros fueron mas altos, en cambio el quinto fue mas bajo. Animales de un ano de edad y mas, tenian un cuerpo significativamente mas pesado y un cerebro de mayor longitud (p < 0.05) que aquellos bajo esta edad. Sin embargo, en estos ultimos fue significativo un peso relativo mas bajo para el encefalo y la cabeza. Los resultados obtenidos en este estudio pueden ser usados en Neuroanatomia Comparada y como base de datos en investigaciones de neuropatologia, farmacologia, anestesiologia y neurofisiologia

The immunohistochemical localization of desmin and smooth muscle actin in the ovary of the African giant rat (Cricetomys gambianus) during the oestrous cycle.

The aim of this study was to describe the distribution of smooth muscle actin and desmin immunopositive cells in the ovary of the giant rat. In addition, the study describes the morphological changes in the ovary of this species during the oestrous cycle. Healthy secondary and tertiary follicles dominated the ovary during pro‐oestrus and oestrus. The theca externa of the tertiary follicles was immunopositive for smooth muscle actin, but immunonegative for desmin. Oestrus was also characterized by the presence of corpora haemorrhagica, which had an outer layer of smooth muscle actin immunopositive cells. Differentiating corpora lutea were observed during metoestrus. A further notable feature of the ovary during metoestrus was the presence of numerous atretic secondary and tertiary follicles. In the later stages of atresia, the follicles were infiltrated by desmin and smooth muscle actin immunopositive cells. Dioestrus was characterized by the presence of non‐regressing and regressing corpora lutea. Immunostaining for smooth muscle actin was demonstrated in the enclosing layer of the corpora lutea, as well as in the tunica media of blood vessels within the corpora lutea. The results of this study have shown that morphological changes in the ovary of the giant rat during the oestrus cycle are similar to those of laboratory rodents. Furthermore, the results of the immunohistochemical study indicate that the perifollicular distribution of desmin and smooth muscle actin cells changes during follicular development and atresia.

Immunohistochemical localization of the progesterone and oestrogen α receptors in the uterine horns of the African giant rat (Cricetomys gambianus).

The present study investigated the immunolocalization of the progesterone and oestrogen α receptors in the uterine horns of the African giant rat during the oestrous cycle. The progesterone and oestrogen α receptors were demonstrated in various cellular constituents of the endometrium, myometrium and perimetrium. The intensity of progesterone and oestrogen α receptor immunostaining in the endometrial and myometrial layers of the uterine horns varied during the oestrous cycle. The intensity of oestrogen α receptor immunoreactivity in the luminal epithelium was high during pro‐oestrus, oestrus and dioestrus. Progesterone and oestrogen α receptor immunoreactivity in the endometrial epithelia was absent during metoestrus. Moderate to strong immunostaining for the progesterone and oestrogen α receptors was demonstrated in the myometrial smooth muscle cells during pro‐oestrus, oestrus and dioestrus. The intensity of progesterone and oestrogen α receptor immunostaining in the myometrial smooth muscle cells was low during metoestrus. Stromal cells in the perimetrium consistently expressed progesterone and oestrogen α receptor immunoreactivity throughout the oestrous cycle. The findings of the study indicate that in the giant rat the immunolocalization of the progesterone and oestrogen α receptors, in endometrial and myometrial regions of the uterine horns, varies during the oestrous cycle.

Characterization of the Uterus and Mammary Glands of the Female African Giant Rats (Cricetomys gambianus, Waterhouse) in Nigeria

La morfologia del utero y las glandulas mamarias fueron estudiadas en ratas Africanas gigantes sexualmente maduras. El utero fue identificado como doble, teniendo dos cuernos uterinos separados y dos cervix. Los dos cervix estaban parcialmente fusionados y separados por un tabique mediano sagital. Su grosor muscular se proyecta caudalmente en la vagina como la porcion vaginal del cuello uterino. Los resultados tambien mostraron que ocho glandulas mamarias, distribuidas a lo largo de las zonas laterales de torax y la region inguinal estaban presentes. La region toracica e inguinal tenia cuatro glandulas mamarias en cada lado y se organizaron en dos pares de filas craneales y caudales. Estos hallazgos completan algunas lagunas creadas por la escasez de informacion sobre la biologia reproductiva de la rata gigante Africana hembra.

Caudofrontal Depression on the Cornual End of the Temporal Line of the Skull of Goat Breeds in Nigeria

Un estudio comparativo fue efectuado en 65 craneos obtenidos de tres diferentes razas de cabras en Nigeria: Red Sokoto, Sahel y West African Dwarf. Una unica depresion fue encontrada en el final del cuerno de la linea temporal del craneo medial, al limite de la porcion media con la caudal de la orbita y dorsal a la porcion lateral de la sutura frontoparietal. La depresion fue encontrada en todas las cabras estudiadas, en ambo sexos, en el lado lateral de ambos procesos corneales de los huesos frontales. La medidas (profundidad, altura y ancho) de la depresion no tenian relacion con edad o sexo de las razas de cabras. La literatura no aporto ninguna informacion de la depresion en el craneo de la cabra. Por lo tanto, proponemos denominarla depresion caudofrontal

Melatonin ameliorates bisphenol A-induced perturbations of the prostate gland of adult Wistar rats

Bisphenol A (BPA) is an endocrine disrupting chemical (EDC) that has been demonstrated to induce alterations in reproductive organs while melatonin (ML), an antioxidant, present in plants and animals, is capable of protecting against EDC-induced alterations. Adult male Wistar rats (average weight, 240 + 10 g) were divided into four groups of ten animals each: Rats in group I (control) received oral 0.2 ml 1% dimethyl sulfoxide (DMSO)/99% canola oil as vehicle; group II received intra-peritoneal 10 mg/kg BW/day ML. Group III received oral BPA dissolved in DMSO and solubilized in canola oil at 10 mg/kg BW/day. Group IV were treated with same dose of BPA as group III with a concomitant intra-peritoneal 10 mg/kg BW/day ML. All treatments lasted for 14 days. BPA significantly increased the prostatic index of the rats while ML ameliorated it. BPA significantly increased serum levels of estrogen as well as prostate-specific antigen but decreased serum testosterone in the rats while concomitant treatment with ML ameliorated these alterations. Also, BPA caused vascular congestion, hyperplasia (functional, reactive and atypical) of prostatic epithelium as well as tubular atrophy the rats while ML attenuated the observed lesions. Decreased localization of αSmooth muscle actin, vimentin and S100 proteins were observed in the BPA-treated rats while these decreases were ameliorated by ML. The present study has shown that sub-acute oral administration of BPA induced alterations in prostatic index, serum hormone levels, down-regulated protein localization and induced morphological lesions of the prostate gland in rats while concomitant treatment with intra-peritoneal ML ameliorated these conditions. Hence, low dose of ML can protect against BPA-induced toxicity of the prostate gland of rats.

Anatomical and Immunohistochemical Characteristics of the Prostate Gland in the Greater Cane Rat (Thryonomys swinderianus)

This study examined the morphology and immunohistochemical features of the prostate gland in 15 captive‐reared male greater cane rat of known reproductive and medical history. Samples of the glands were taken after gross examination and routinely prepared for both histological and ultrastructural analysis. Immunohistochemistry was also carried out on paraffin‐embedded sections of the glands using rabbit polyclonal antibodies against oestrogen receptors (ERα and ERβ) and mouse monoclonal antibody for the progesterone receptor (PR). The prostate, which constitutes 0.04% of the body weight, was a paired, lobulated, brownish gland having three left and four right lobes that partly cover the pelvic urethra. Based on the amount and arrangement of the secretory epithelial folding and relative to their distances to the urethra, two histological zones, the central and peripheral, were identified. However, the epithelium of both zones was lined by predominantly simple cuboidal cells with occasional basal cells. The main ultrastructural features of these cuboidal cells were the presence of several nuclear pores on the nucleus, moderately well‐developed, short microvilli and bleb‐like apical projections, as well as inter‐cellular lacunae seen between these cells and the basal cells. The cuboidal epithelial cells also showed positive nuclear staining for ERα and ERβ but not for PR. It is however interesting that the ERα‐positive staining was more at the epithelial cells, which is uncommon. These findings highlight the peculiarities in the structure and ultrastructure as well as the unique expression of the oestrogen receptors in the prostate gland of the greater cane rat.

Gross, Histological and Ultrastructural Features of the Bulbourethral Gland in the Greater Cane Rat (Thryonomys swinderianus)

The present study examines the structure and ultrastructure of the bulbourethral glands in 10 sexually matured male greater cane rats raised in captivity. Following anaesthesia, the rats were perfusion‐fixed transcardially and the bulbourethral glands dissected out. Upon morphologic and morphometric analysis, the Cowpers glands were observed to have an average volume of 0.24 ± 0.08 ml, a diameter of 6.3 ± 0.6 mm and weighs 0.199 ± 0.06 g. The paired, gourd‐shaped tubuloalveolar glands were surrounded by dense connective tissues and separated into lobules by capsular septae. Each lobule consists of endpiece/secretory units and excretory ducts lined by simple glandular epithelium and pseudo‐stratified epithelium, respectively. The round end pieces consisted of 8–10 pyramidal to columnar epithelial cells with flattened, basally located nuclei and granule‐filled cytoplasm that bounded a narrow glandular lumen. The striking ultrastructural features of these secretory cells were the presence of some granules with uniform electron density and those with regions of lesser density as well as the absence of secretory vacuoles. Another unique characteristic of these secretory granules is the presence of electron dense strands radiating from their surfaces. The apical surfaces of the cells were also studded with abundant microvilli. From the findings, the structure of bulbourethral glands in the greater cane rat shows more resemblances to that of humans than to its rodent phylogeny. These findings serve as additional knowledge in the structural interpretation of the bulbourethral gland and its secretory products.

Spermatogenic cycle of the African sideneck turtle Pelusios castaneus (Schweigger, 1812) (Reptilia: Testudines)

Abstract We describe the spermatogenic cycle of the African sideneck turtle (Pelusios castaneus) (Reptilia: Testudines). We further classify the pattern of spermatogenesis in the species, generating new comparative baseline data on the spermatogenic cycle of freshwater turtles in the tropics. Seventy-two adult male P. castaneus collected at different times from various river drainages in Ibadan, Nigeria, were used for the study. The average body weight of the turtles was 723 ± 23.36 g while the curved carapace and plastron lengths of the turtles were 24.4 ± 1.47 cm and 15.7 ± 1.23 cm, respectively. Histology of the testis and epididymis, gonadosomatic index, epididymal mass index, seminiferous tubule diameter and epididymal ductal diameter all suggest the postnuptial pattern of spermatogenesis. Sperm production in P. castaneus starts in May and peaks in September. It is thereafter released into the epididymis, and the degree of sperm packing of the epididymis increases from October, reaching its peak in January. Spermatozoa were found in the epididymis of the turtles all through the year. The study shows that the postnuptial pattern of turtle spermatogenesis is not unique to turtles in the temperate regions of the world and that the spermatogenic cycle of P. castaneus is similar to those of other chelonians with minor variations. This report, the first of its kind for a pelomedusid turtle, therefore serves as baseline information for the family in comparative studies of the spermatogenic cycle of turtles.