Morphological changes in tissues/organs of weanling Albino rats exposed to graded doses of popular brands of pyrethroids-containing insecticidesmosquito coil and aerosolized spray were studied over a period of 18 days. Rats were exposed to 0.4, 0.8, 1.2 and 1.6mg/kg BW of active ingredients in aerosolized insecticidal spray for 15, 30, 45 and 60 seconds, in two divided doses daily for 18 days. Control rats were not exposed. Early clinical signs include irritability, head shaking and scratching of nostrils; these later gave way to sneezing, gurgling, fine muscular tremors, ruffled fur, lethargy and depression. No self-death was recorded in all the exposed and control groups. Gross changes were not apparent in most organs, but for pulmonary oedema and slight hepatomegaly and palor of kidneys in rats exposed to high doses of the fumes sacrificed on days 12, 15 and 18 post-exposure. Histopathology revealed varying degrees of vacuolar degeneration and necrosis of hepatocyctes, myocardiac degeneration, glomerular and tubular degeneration and necrosis, meningitis, neuronophagia, demyelination of neuronal axons and exudative pnuemonia. Others include blood vascular damage, haemorrhages, vasculitis and thrombosis in many organs, and Kuppfer and intestinal goblet cells hyperplasia. The severity of the lesions was dose and time dependent. The lesions observed suggest interference with tissue energy metabolism and widespread vascular damage and multi-organ degeneration and necrosis. The implications of the consistent and uncontrolled use of pyrethroids-containing insecticides on farm and market produce and in human inhabitants and their effects on public health and biodiversity conservation are discussed.(Afr. J. Biomed. Res. 11: 97 -104)
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 Cowper's 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.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.