The pesticide heptachlor affects steroid hormone secretion in isolated follicular and luteal cells of rat.

Heptachlor, a chlorinated hydrocarbon pesticide, suppresses the production of progesterone and estradiol in the female rat in vivo or in isolated ovaries in vitro. In this study the effect of heptachlor on steroid hormone production by isolated rat luteal and follicular cells, in the presence of two precursor hormones was investigated. Ovaries were isolated from anesthetized mature normocyclic virgin rats (3 to 4 months old), under sterile conditions.

Ultrastructure of the chorioallantoic placenta and chorionic vesicles of the lesser bush baby (Galago senegalensis).

The ultrastructure of the chorioallantoic placenta of the lesser bush baby (Galago senegalensis) has been studied. The placenta was shown to be of the diffuse, epitheliochorial and adeciduate type. The trophoblasts of the chorionic villi, other than those lining the chorionic vesicles, were characterized by the presence of many lipid droplets.

Frequency of stages of the seminiferous cycle in the thick-tailed bush baby (Otolemur garnetti), a prosimian primate: possible phylogenetic implications?

Spermatogenesis in the thick-tailed bush baby, Otolemur garnetti, was studied using light microscopy. The stages and stage frequencies of the cycle of the seminiferous epithelium were determined using semithin sections stained with methylene blue-azure II. These sections were obtained from the testes of six healthy adult males (n = 6).

Placenta and fetal membranes of the four-toed elephant shrew, Petrodromus tetradactylus.

The four-toed elephant shrew is the only extant member of the genus Petrodromus. Some features of its placentation are found in other elephant shrews and may be important in consolidating the elephant shrews in the order Macroscelidea. These include implantation in an embryo chamber at the caudal end of the uterine horn; a large yolk sac; a large, lobulated allantoic sac; a distinct layer of proliferative trophoblastic cells between the labyrinthine and spongy zones of the placenta; an accessory epitheliochorial placenta; and the formation of a mesoplacenta by the decidua basalis.

Placentation in species of phylogenetic importance: the Afrotheria.

Afrotheria, one of four mammalian superorders, comprises elephants, sea cows, hyraxes, aardvark, elephant shrews, tenrecs and golden moles. Their placentas either form an equatorial band or are discoid in shape. The interhemal region, separating fetal and maternal blood, is endotheliochorial in elephants, aardvark and possibly the sea cows, but hemochorial in the remaining orders.

Early testicular response to intraperitoneal administration of ethane dimethanesulphonate (EDS) in the goat (Capra hircus).

Early morphological changes in the goat testis after a single intraperitoneal injection of ethane dimethanesulphonate (EDS) were investigated using both light and electron microscopy. The compound was administered at two dose levels: 75 mg/kg and 25 mg/kg. While the former resulted in some deaths due to toxicity, the latter had no noticeable toxic effects on the animals.

Morphological characterization of the seminiferous cycle in the goat (Capra hircus): a histological and ultrastructural study.

The cycle of spermatogenesis/seminiferous cycle was investigated in the goat testis using both light and electron microscopy techniques. Using the various cell associations and the accompanying changes in spermatid shape and location, the cycle was divided into eight (8) successive stages. The cycle began with the accomplishment of spermiation (stage 1) and ended with apical migration and close attachment of late maturation phase spermatids at the Sertoli cell apex accompanied by adluminal retention of residual bodies with dense staining inclusions (stage 8).

Morphology of a six-legged goat with duplication of the intestinal, lower urinary, and genital tracts.

Background: An adult female goat with rare malformations, which consisted of duplication of the intestinal, lower urinary, and genital tracts as well a pair of parasitic appendages, is presented.

Methods: A complete dissection was performed on a moribund female goat (Capra hircus).

Results: The animal had a normal body with a parasitic attachment located within the pelvic region.

In vivo and in vitro effects of graded doses of the pesticide heptachlor on female sex steroid hormone production in rats.

Adult female Sprague-Dawley rats were injected with corn oil or 5 mg, 20 mg, 25 mg or 30 mg per kg body weight of heptachlor solution every other day for up to 18 days. The rats were killed at the end of the experimental period, and blood samples were assayed for progesterone and oestrogen by radioimmunoassay. Ovarian cells from the rats were isolated and incubated either on their own, or in the presence of LH or FSH, and production of progesterone and oestrogen determined.

Effects of graded doses of the pesticide heptachlor on body weight, mating success, oestrous cycle, gestation length and litter size in laboratory rats.

Adult female Sprague-Dawley rats were injected with 5 or 20 mg/kg body weight heptachlor solution every other day for up to 18 days. They were weighed every day and the stage of oestrus determined by vaginal smears. One experimental group was mated and pregnancy characteristics studied.

Effects of 6-hydroxydopamine on testosterone production by mouse leydig cells in vitro.

Increasing doses (15 to 1000 micrograms/ml) of 6-hydroxydopamine (6-OHDA) stimulated, then suppressed testosterone production by mouse leydig cells incubated for 3 h in vitro. The stimulating doses ranged between 50 and 100 micrograms/ml, with maximal effects occurring at 30 to 60 minutes after the start of the treatments. At doses of 500 micrograms/ml, 6-OHDA exhibited inhibitory effects.

Ultrastructural study of the testis of non-breeding naked mole-rat (Heterocephalus glaber, Ruppell).

The testicular structure of the wild caught naked mole rat was studied. It comprises of a large volume of lipid-rich interstitial cells of Leydig among which are few scattered seminiferous tubules. In addition, the interstitial cells possess elongated mitochondria and vast network of smooth endoplasmic reticulum (sER).

The interhemal membrane of the spotted hyena: an immunohistochemical reappraisal.

On the basis of specific immunohistochemical staining for vimentin and cytokeratin, we conclude that in the mature placenta of the spotted hyena the interhemal membrane is haemomonochorial rather than endotheliochorial, as in other carnivores. We concur that the intrasyncytial laminae are remnants of the maternal endothelial basal lamina.

Plasma testosterone in Trypanosoma congolense-infected Toggernburg goats.

Trypanosomiasis induces histological testicular degenerative changes leading to suppression of spermatogenesis in goats and laboratory animals. We present evidence associating these changes with trypanosome-induced endocrine dysfunction. Toggenburg goats were infected with approximately 100,000 trypanosomes.

An electron microscopic study of the chorioallantoic placenta and the subplacenta of the cane rat (Thryonomys swinderianus Temminck).

The ultrastructure of the cane rate chorio-allantoic placenta has been studied. In its thinnest regions the interhaemal membrane is composed of a single layer of syncytiotrophoblast, a common basal lamina, and the fetal capillary endothelium. Hence this is a haemomonochorial placenta.

Histology of the chorioallantoic placenta of the golden-rumped elephant shrew (Rhynchocyon chrysopygus Gunther, 1881).

The chorioallantoic placenta of the golden-rumped elephant shrew, Rhynchocyon chrysopygus has been studied. The implantation is eccentric and mesometrial. The placenta is haemochorial and is divisible into 4 zones namely columnar, proliferative, spongy and basal trophoblastic zones.

Electron microscopic study of the chorioallantoic placenta of the rock hyrax (Heterohyrax brucei).

The interhaemal membrane consisted of only two cellular elements: a single layer of cellular trophoblast and the fetal capillary endothelium. The hyrax is therefore one of the few mammals known to possess the cellular haemomonochorial type of placenta. The trophospongium was also cellular while the basal trophoblastic cells were strongly phagocytic.

The chorioallantoic placenta of the spotted hyena (Crocuta crocuta Erxleben): an electron microscopic study.

The histology and ultrastructure of the chorioallantoic placenta of the spotted hyena have been studied in three specimens obtained in the field and fixed promptly with glutaraldehyde. Observations revealed that the interhemal membrane at its minimal thickness is hemomonochorial, consisting of a continuous layer of syncytial trophoblast, a basal lamina, and fetal capillary endothelium. Cytotrophoblastic cells form a discontinuous layer beneath the syncytial trophoblast and are distinguished by the presence of numerous extracted lipid droplets in their cytoplasm.

Gonadal and plasma testosterone and cholesterol in scorbutic guinea pigs.

Testes of pre- and post-pubertal guinea pigs were examined histologically and biochemically to see if ascorbic acid deficiency brought about any changes in their structure or function. Apart from a slight but significant fall in gonadal cholesterol there was no apparent change in the histology or testosterone content in scorbutic guinea pigs. Plasma cholesterol and testosterone were also similar in the control and scorbutic animals.

Histochemistry of the duodenal glands of the cat and horse.

The duodenal glands of cat and horse were studied using PAS, Alcian blue, dialysed iron, aldehyde fuchsin-Alcian blue and high iron diamine stains. It was found that the duodenal glands of the horse reacted positively to Alcian blue, dialysed iron stains and also took the Alcian blue stain in the combined aldehyde fuchsin-Alcian blue and high iron diamine-Alcian blue stains. Those of the cat gave negative results.